Non-Domestic Building Services Compliance Guide and...Section 8: Domestic hot water 43 8.1 Introduction 43 8.2 Scope of guidance 43 8.3 Key terms 44 8.4 Domestic hot water systems

2013 edition – for use in England*

Non-Domestic Building Services Compliance Guide

Compliance G

uide N

on-Dom

estic Building Services

O N L I N E V E R S I O N


* Note: Any reference to the Building Regulations in this guide is to the Building Regulations 2010 in England (as amended). These Regulations also apply to the following building work in Wales:

(a) work on an excepted energy building as defined in the Schedule to the Welsh Ministers (Transfer of functions) (No 2) Order 2009 (SI 2009/3019); and

(b) work that is subject to provisions of the regulations relating to energy efficiency specified in regulation 34 of the Regulations and is carried out to educational buildings, buildings of statutory undertakers and Crown buildings, or carried out by Crown authorities.

This guidance comes into effect on 6 April 2014. Work started before this date remains subject to the earlier edition of the guidance. Work subject to a building notice, full plans application or initial notice submitted before this date will also remain subject to the earlier edition of the guidance, provided it is started before 6 April 2015.

For other jurisdictions in the UK, it will be necessary to consult their own building regulations and guidance.



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Contents

Contents

Section 1: Introduction 51.1 Scope 5

1.2 Innovativesystems 6

1.3 Europeandirectives 6

1.4 Statusofguide 7

1.5 Howtousethisguide 8

1.6 Keytermsforspaceheatinganddomestichotwatersystems 8

1.7 Summaryofrecommendedminimumenergyefficiencystandards 9

Section 2: Gas, oil and biomass-fired boilers 142.1 Introduction 14

2.2 Scopeofguidance 14

2.3 Keyterms 14

2.4 Determiningboilerseasonalefficiency 16

2.5 Boilersinnewbuildings 19

2.6 Boilersinexistingbuildings 20

2.7 Heatingefficiencycreditsforreplacementboilers 21

2.8 Biomassboilers 24

Section 3: Heat pumps 253.1 Introduction 25


3.3 Keyterms 26

3.4 Heatpumpsinnewandexistingbuildings 26

3.5 Heatingefficiencycreditsforheatpumpsystemsinexistingbuildings 28

3.6 Supplementaryinformation 30

Section 4: Gas and oil-fired warm air heaters 314.1 Introduction 31


4.3 Keyterms 31

4.4 Warmairheatersinnewandexistingbuildings 32

4.5 Heatingefficiencycreditsforwarmairheatersinnewandexistingbuildings 32

* Note: Any reference to the Building Regulations in this guide is to the Building Regulations 2010 in England (as amended). These Regulations also apply to the following building work in Wales:

(a) work on an excepted energy building as defined in the Schedule to the Welsh Ministers (Transfer of functions) (No 2) Order 2009 (SI 2009/3019); and

(b) work that is subject to provisions of the regulations relating to energy efficiency specified in regulation 34 of the Regulations and is carried out to educational buildings, buildings of statutory undertakers and Crown buildings, or carried out by Crown authorities.

This guidance comes into effect on 6 April 2014. Work started before this date remains subject to the earlier edition of the guidance. Work subject to a building notice, full plans application or initial notice submitted before this date will also remain subject to the earlier edition of the guidance, provided it is started before 6 April 2015.

For other jurisdictions in the UK, it will be necessary to consult their own building regulations and guidance.



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Non-Domestic Building Services Compliance Guide: 2013 Edition

Section 5: Gas and oil-fired radiant heaters 345.1 Introduction 34


5.3 Keyterms 34

5.4 Radiantheaters 35

5.5 Heatingefficiencycreditsforradiantheatersinexistingbuildings 35

Section 6: Combined heat and power and community heating 376.1 Introduction 37


6.3 Keyterms 37

6.4 CHPinnewandexistingbuildings 38


Section 7: Direct electric space heating 407.1 Introduction 40


7.3 Electricspaceheatinginnewandexistingbuildings 40

Section 8: Domestic hot water 438.1 Introduction 43


8.3 Keyterms 44

8.4 Domestichotwatersystemsinnewandexistingbuildings 46

8.5 Supplementaryinformationonelectricwaterheaters 48

8.6 Heatingefficiencycreditsfordomestichotwatersystemsinnewandexistingbuildings 49

Section 9: Comfort cooling 519.1 Introduction 51


9.3 Keyterms 51

9.4 Comfortcoolinginnewandexistingbuildings 52

9.5 CalculatingtheseasonalenergyefficiencyratioforSBEM 53




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Contents

Section 10: Air distribution 5610.1 Introduction 56


10.3 Keyterms 56

10.4 Airdistributionsystemsinnewandexistingbuildings 57

10.5 Heatrecoveryinairdistributionsystemsinnewandexistingbuildings 61

10.6 CalculatingthespecificfanpowerforSBEM 61

Section 11: Pipework and ductwork insulation 6211.1 Introduction 62


11.3 Insulationofpipesandductsinnewandexistingbuildings 62

Section 12: Lighting 6512.1 Introduction 65


12.3 Keyterms 65

12.4 Lightinginnewandexistingbuildings 66

12.5 LightingEnergyNumericIndicator(LENI) 68

Section 13: Heating and cooling system circulators and water pumps 7113.1 Introduction 71


13.3 Keyterms 71

13.4 Glandlesscirculatorsandwaterpumpsinnewandexistingbuildings 71


Appendix A: Abbreviations 72



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Non-Domestic Building Services Compliance Guide: 2013 EditionO N L I N E V E R S I O N


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Section 1: Introduction

Section1: Introduction

1.1 ScopeThisguideprovidesdetailedguidancefortheinstallationoffixedbuildingservicesinnewandexistingnon-domesticbuildingstohelpcompliancewiththeenergyefficiencyrequirementsoftheBuildingRegulations.

Thiseditioncoversthedesign,installationandcommissioningof:

• conventionalmeansofprovidingprimaryspaceheating,domestichotwater,mechanicalventilation,comfortcoolingandinteriorlighting

• lowcarbongenerationofheatbyheatpumpsandcombinedheatandpowersystems.

Theguidesetsoutrecommendedminimumenergyefficiencystandardsforcomponentsofbuildingservicessystems,includingtheuseofcontrols.Forsystemsinstalledinnewbuildings,thestandardsaredesignlimits(orbackstopvalues).Forneworreplacementsystemsandcomponentsinstalledinexistingbuildings,thestandardsrepresentreasonableprovisionforcomplyingwiththeBuildingRegulations.

Itisimportanttonotethatstandardshigherthanmanyoftheserecommendedminimumstandardswillneedtobeachievedif:

• newbuildingsaretomeetthetheBuildingRegulationstargetcarbondioxideemissionrate(TER)calculatedusingNationalCalculationMethodology(NCM)toolssuchasSBEM1

• systems(upto45kWheatoutput)aretocomplywiththeMicrogenerationCertificationSchemestandardsthatenablebuildingownerstoreceivepaymentsundertheRenewableHeatIncentive(RHI)andqualifyforGreenDealfunding

• productsaretoberecognisedasrenewabletechnologiesundertheRenewableEnergyDirective.

Theguideincludessomesupplementaryinformationthatidentifiesgoodpracticedesignandinstallationstandardsthatexceedtheminimumstandardsinthisguide.MicrogenerationCertificationSchemestandards2areanexampleofgoodpracticestandards.

Inrelevantsections,theguideidentifiesadditionalnon-prescriptivemeasures(forexampleadditionalcontrols)thatcanimproveplantefficiency.Thesemaybeusedtogain‘heatingefficiencycredits’tohelpmeetthecarbondioxideemissiontargetsfornewbuildings,ortherecommendedminimumenergyefficiencystandardssetoutinthisguideforworkinexistingbuildings.

AsummaryofrecommendedminimumenergyefficiencystandardsispresentedinTable1attheendofthissection.

1 TheNationalCalculationMethodology(NCM)modellingguideandtheSimplifiedBuildingEnergyModel(SBEM)toolcanbedownloadedfromwww.ncm.bre.co.uk.2 http://www.microgenerationcertification.org/mcs-standards



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1.2 InnovativesystemsItisalsoimportanttonotethatthisguidecoversarangeoffrequentlyoccurringsituations.Itdealswiththemostcommonlyusedfixedbuildingservicestechnologies.IndoingsoitneitherendorsesthesemethodsandtechnologiesnorexcludesothermoreinnovativetechnologiesthatmayofferanalternativemeansofmeetingthefunctionalrequirementsoftheBuildingRegulations.

Wherethealternativetechnologyhasbeenthesubjectofarecognisedtestingprocedurethatassessesitsenergyperformance,thismaybeusedtoindicatethatthesystemisadequatelyefficient.Intheeventthatthereisnorecognisedtestingstandard,suitablecalculationsormodellingmethodsmaybeusedtoshowthecarbonperformanceofthesystem.

1.3 EuropeandirectivesThedesignandinstallationoffixedbuildingservicesproducts,suchasboilers,circulatorsandheatpumps,shallattheappropriatetimecomplywithallrelevantrequirementsofEUdirectivesasimplementedintheUnitedKingdom.Thereareanumberofdirectiveswithrequirementsthatdirectlyorindirectlycontroltheenergyefficiencyofbuildingservices.

TheEcodesign Directive 2009/125/ECprovidesaframeworkforestablishingrequirementsfor‘energy-related’productsplacedontheEUmarket.Currentrequirementscover‘energy-using’productssuchasboilers,lightbulbsandwashingmachines.Inthefuture,requirementswillalsocoverproductssuchaswindows,insulationmaterialandshowerheadswhoseusehasanimpactonenergyconsumption.

TherequirementsaresetoutinCommissionRegulationslistedinthedocumenthttp://ec.europa.eu/energy/efficiency/ecodesign/doc/overview_legislation_eco-design.pdf.ProductscoveredbytheregulationscanonlybeCEmarkedandplacedonthemarketiftheymeettheecodesignstandardsspecified.

Atthetimeofpreparationofthisguide,CommissionRegulationsexistedorwerebeingdevelopedfor:

• spaceheatersandcombinationheaters

• waterheatersandhotwaterstoragetanks

• glandlessstandalonecirculatorsandglandlesscirculatorsintegratedinproducts

• waterpumps

• airconditionersandcomfortfans

• fansdrivenbymotorswithanelectricinputpowerbetween125Wand500kW

• lightingproductsinthedomesticandtertiarysectors

• electricmotors.

TheintentionisthattherecommendedminimumproductstandardsinthisguideshouldatleastmatchtheenergyefficiencystandardssetoutinCommissionRegulationsas they come into force.Forexample,althoughtheimplementingregulationsforhotwaterstoragetankswerepublishedinSeptember2013,thestandardsdonotcomeintoforceuntilSeptember2017.

If in any doubt as to whether a product is subject to minimum ecodesign standards, check the Commission document above.

TheEnergy Labelling Directive 2010/30/EUcomplementstheEcodesignDirectivebyprovidingaframeworkforlabellingofenergy-relatedproductsincludinglamps,luminaires,householdairconditionersandwashingmachines.TheEnergyLabelclassifiesproductsonanAtoGscale,‘pulling’themarkettowardsmoreefficientproductsbybetterinformingconsumers.TheEcodesignDirective,bycontrast,usesregulationto‘push’themarketawayfromtheworstperformingproducts.



http://ec.europa.eu/energy/efficiency/ecodesign/doc/overview_legislation_eco-design.pdf

http://ec.europa.eu/energy/efficiency/ecodesign/doc/overview_legislation_eco-design.pdf

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TheRenewable Energy Directive 2009/28/ECprovidesaframeworkforthepromotionofenergyfromrenewableresources.ItsetsamandatoryUKtargetof15%energygenerationfromrenewablesourcesby2020–the‘renewableenergyobligation’–asacontributiontomeetingtheEU’soveralltargetof20%.Ofrelevancetobuildingservicesisthatitincludescriteriafortrainingandcertificationofinstallersofrenewables.ThedirectivealsospecifiesinAnnexVIIthestandardsthatheatpumpsmustachievetoberecognisedasrenewabletechnologiesbythedirective.

TheEnergy Efficiency Directive2012/27/EUestablishesacommonframeworkofmeasuresforthepromotionofenergyefficiencywithintheEUinordertoensurethattheEUmeetsitstargetofa20%reductioninprimaryenergyconsumptionby2020.LegislationtoimplementthedirectiveintheUKwillbepublishedby5June2014.Includedwillberequirementsforpublicauthoritiestopurchaseonlyenergy-efficientproducts,servicesandbuildings;andrequirementsforheatmeterstobefittedinapartmentsandbuildingsconnectedtoacentralsourceofheatingordistrictheatingnetwork.Formoreinformationonthespecificrequirementsandtechnicalstandards,seetheDECCwebsite3.

TheEnergy Performance of Buildings Directive2010/31/EUisarecastoftheoriginal2002/91/ECdirective,whichin2002introducedrequirementsfor:

• theestablishmentofamethodologyforcalculatingtheintegratedenergyperformanceofbuildings

• minimumenergyperformancerequirementsfornewbuildings,and,wherefeasible,forlargerbuildingsundergoingmajorrenovation

• energyperformancecertificationofbuildings,and

• inspectionsofheatingandairconditioningsystems.

Therecastdirectiveincludesanewrequirementtoconsider,inthedesignofnewbuildings,thefeasibilityofusingrenewablesandother‘high-efficiencyalternativesystems’.Thereisnomandatoryformatforthisassessment,butitwillnowbenecessarytodeclare(throughanewfieldintheenergyperformancecalculationsoftware)thatithasbeencarriedout.

TheBuildingRegulations,whichalreadymettheoriginalrequirementsinmanyways(forexamplebysettingstandardsfornewbuildings),havebeenamendedinsomeplacestoreflectthenewrequirementsofthedirective.Forguidanceonthechangesaffectingnewbuildings,seeApprovedDocumentL2A.Forguidanceonthechangesaffectingmajorrenovations,seeApprovedDocumentL2B.Forguidanceonotherrequirementsrelatingtobuildingcertificationandinspectionofheatingandairconditioningsystems,seetheDCLGwebsite4.

1.4 StatusofguideTheBuildingRegulationscontainfunctionalrequirements,suchasrequirementsthatbuildingsmustbestructurallystable,constructedandfittedtoensurefireprotection,andenergyefficient.Thesefunctionalrequirementsareoftendraftedinbroadterms,andsoitmaynotalwaysbeimmediatelycleartoapersoncarryingoutworkhowtocomplywiththerelevantrequirements.Consequently,theDepartmentforCommunitiesandLocalGovernmentissuesdocuments,knownasapproveddocuments,whichprovidepracticalguidanceonwaysofcomplyingwithspecificaspectsoftheBuildingRegulationsinsomeofthemorecommonbuildingsituations.

Approveddocumentsarenotalwayscomprehensiveandmaycontainreferencestootherdocumentswhichwillprovidemoredetailedinformationandassistanceonpartsoftheguidance.Thisguideisoneofthosedocuments:itprovidesmoredetailedinformationontheguidancecontainedinApproved

3 https://www.gov.uk/decc4 https://www.gov.uk/dclg



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DocumentsL2AandL2Baboutcompliancewiththeenergyefficiencyrequirementswhichapplywheninstallingfixedbuildingservicesinnewandexistingbuildings.

Ifyoufollowtherelevantguidanceinanapproveddocument,andinanydocumentreferredtointheapproveddocument(suchasthisguide)whichprovidesadditionalinformationtohelpyoufollowthatguidance,thereisalegalpresumptionthatyouhavecompliedwiththeBuildingRegulations.However,ineachcaseitisforthebuildingcontrolbody(localauthorityorapprovedinspector)todecidewhetherworkcomplieswiththerequirementsoftheBuildingRegulations.ItisthereforesensiblethatyoucheckwiththebuildingcontrolbodybeforestartingworkwhattheyconsideritisnecessaryforyoutodotocomplywiththerequirementsoftheBuildingRegulations.

1.5 HowtousethisguideTheguideisdividedintothefollowingsections:

Section1:Introductionandsummaryofenergyefficiencystandards

Section2:Gas,oilandbiomass-firedboilers

Section3:Heatpumps

Section4:Gasandoil-firedwarmairheaters

Section5:Gasandoil-firedradiantheaters

Section6:Combinedheatandpowerandcommunityheating

Section7:Directelectricspaceheating

Section8:Domestichotwater

Section9:Comfortcooling

Section10:Airdistribution

Section11:Pipeworkandductworkinsulation

Section12:Lighting

Section13:Heatingandcoolingsystemcirculatorsandwaterpumps

Supplementaryinformationisshownagainstabluebackground.ThismaybefurtherinformationtohelpwithinterpretingtheminimumenergyefficiencyprovisionsneededtocomplywiththeBuildingRegulations.Oritmaybeguidanceonbestpracticethatgoesbeyondtherecommendedminimumstandards.

Keytermsareprintedinblueandaredefinedatappropriatepointsthroughouttheguide.

1.6 KeytermsforspaceheatinganddomestichotwatersystemsThefollowinggeneraldefinitionsareapplicabletothesectionsthatdealwithspaceheatingandhotwater.Furtherdefinitionsareincludedinlatersectionsasappropriate.

Heatgeneratormeansadeviceforconvertingfuelorelectricityintoheat–e.g.aboilerorradiantheater.

Heatgeneratorefficiencymeanstheusefulheatoutputdividedbytheenergyinputinthefuel(basedongrosscalorificvalue)orelectricitydeliveredtotheheatgenerator,asdeterminedbytheappropriatetestmethodsforthattypeofheatgenerator.

Heatgeneratorseasonalefficiency meanstheestimatedseasonalheatoutputfromtheheatgeneratordividedbytheenergyinput.Thiswilldependontheheatgeneratorefficiencyandtheoperatingmode



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oftheheatgeneratorovertheheatingseason.Forexample,inthecaseofboilersitisa‘weighted’averageoftheefficienciesoftheboilerat30%and100%oftheboileroutput.Forothertechnologiestheheatgeneratorseasonalefficiencymaybethesameastheheatgeneratorefficiency.

Minimumcontrolspackage meansapackageofcontrolsspecifictoeachtechnologythatrepresentstherecommendedminimumprovisionnecessarytomeettheBuildingRegulationsenergyefficiencyrequirements.

Additionalmeasures meansadditionalcontrolsorothermeasuresthatgobeyondtherecommendedminimumcontrolspackageandforwhichheatingefficiencycreditsareavailable.

Heatingefficiencycreditsareawardedfortheprovisionofadditionalmeasures,suchasadditionalcontrols,thatraisetheenergyefficiencyofthesystemandgobeyondrecommendedminimumstandards.Differentcreditsapplytothedifferentmeasuresthatareavailableforheatingandhotwatertechnologies.

Effectiveheatgeneratorseasonalefficiencyisobtainedbyaddingheatingefficiencycredits,whereapplicable,totheheatgeneratorseasonalefficiency:

Effectiveheatgeneratorseasonalefficiency=heatgeneratorseasonalefficiencyheatingefficiencycredits Equation 1

Whererelevant,thisguidesetsstandardsforeffectiveheatgeneratorseasonalefficiencysothataheatgeneratorwithaninherentlylowefficiencymaybeusedincombinationwithadditionalmeasures.

Spaceheatingsystemmeansthecompletesystemthatisinstalledtoprovideheatingtothespace.Itincludestheheatingplantandthedistributionsystembywhichheatingisdeliveredtozones.HeatlossesfromthedistributionsystemcanbeaddressedbyreferencetoguidancebyTIMSAonHVACinsulation5.

Domestichotwatersystemmeansalocalorcentralsystemforprovidinghotwaterforusebybuildingoccupants.

1.7 SummaryofrecommendedminimumenergyefficiencystandardsUnlessspecifiedotherwiseinthisguide,itisrecommendedthat,whereapplicable,buildingservicesareprovidedwithcontrolsthatasaminimumcorrespondtoBandCinBSEN15232:2012Energy performance of buildings. Impact of building automation, controls and building management.

5 TIMSAHVAC guidance for achieving compliance with Part L of the Building Regulationsatwww.timsa.org.uk



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6 EmergingEuropeanregulationsimplementingtheEcodesignDirectivesetminimumstandardsfortheefficiencyofenergy-usingproductsthatcanbeplacedonthemarket.Productsshouldalsocomplywiththesestandardsastheycomeintoeffect.Currentregulationsarelistedathttp://ec.europa.eu/energy/efficiency/ecodesign/doc/overview_legislation_eco-design.pdf.

7 Efficiencyisheatoutputdividedbycalorificvalueoffuel.Thenetcalorificvalueofafuelexcludesthelatentheatofwatervapourintheexhaust,andsoislowerthanthegrosscalorificvalue.EfficiencytestresultsandEuropeanstandardsnormallyusenetcalorificvalues.

8 Seasonalcoefficientofperformance(SCOP)isthecurrentEcodesignDirectivemeasureforspaceheatingair-to-airheatpumpswithanoutputofupto12kW.Eventually,themeasureusedwillbetheseasonalprimaryenergyefficiencyratio(SPEER),withtestingandratingtoBSEN14825:2013Air conditioners, liquid chilling packages and heat pumps with electrically driven compressors for space heating and cooling. Testing and rating at part load conditions and calculation of seasonal performance.EnergylabellingwiththeSPEERratingwillbemandatoryfrom2015.

9 RatingconditionsarestandardisedconditionsprovidedforthedeterminationofdatapresentedinBSEN14511:2013Air conditioners, liquid chilling packages and heat pumps with electrically driven compressors for space heating and cooling.

Table 1 Recommended minimum energy efficiency standards for building services6

Gas, oil and biomass-fired boilers:new buildings Seasonal efficiency (gross7)

Naturalgas Single-boilersystem2MWoutput 91%

Single-boilersystem2MWoutput 86%

Multiple-boilersystem 82%foranyindividualboiler86%foroverallmulti-boilersystem

LPG Single-boilersystem2MWoutput 93%

Single-boilersystem2MWoutput 87%


Oil Single-boilersystem 84%


Biomass–independent,automatic,pellet/woodchip 75%

Gas, oil and biomass-fired boilers:existing buildings

Seasonal efficiency (gross)

Actual Effective

Naturalgas 82% 84%

LPG 83% 85%

Oil 84% 86%

Biomass–independent,automatic,pellet/woodchip 75%

Heat pump units Coefficient of performance (COP)

Air-to-air Spaceheating12kW SeasonalCOP‘D’ratingformediantemperaturerangeinBSEN148258

Allothersexceptabsorptionandgas-engine

Spaceheating 2.5(250%)atratingconditionsinBSEN145119

Domestichotwater 2.0(200%)atratingconditionsinBSEN14511

Absorption 0.5(50%)whenoperatingattheratingconditions

Gas-engine 1.0(100%)whenoperatingattheratingconditions



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Table 1 Recommended minimum energy efficiency standards for building services (continued)

Gas and oil-fired warm air systems Thermal efficiency (net)

Gas-firedforcedconvection(naturalgas) 91%

Gas-firedforcedconvection(LPG) 91%

Directgas-firedforcedconvection 100%

Oil-firedforcedconvection 91%

Radiant heaters

Efficiency (net)

Thermal Radiant

Luminousradiantheater(unflued) 86% 55%

Non-luminousradiantheater(unflued) 86% 55%

Non-luminousradiantheater(flued) 86% 55%

Multi-burnerradiantheater 91% N/A

Combined heat and power (CHP) CHPQAquality index Power efficiency

Alltypes 105 20%

Electric (primary) heating Seasonal efficiency

Boilerandwarmair N/A

Domestic hot water systems

Heat generator seasonal efficiency (gross)

Thermal efficiencyBoiler seasonal efficiency

Direct-fired:newbuildings

Naturalgas30kWoutput 90%


LPG30kWoutput 92%

LPG30kWoutput 74%

Oil 76%

Direct-fired:existingbuildings

Naturalgas 73%

LPG 74%

Oil 75%

Indirect-fired(dedicatedhotwaterboiler)*:newandexistingbuildings

Naturalgas 80%

LPG 81%

Oil 82%

*SeeTable26formethodofcalculatingefficiencyforprimaryreturntemperaturesor55°C.

Electrically-heated:newandexistingbuildings N/A



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Comfort cooling systems Energy efficiency ratio (EER)

Packagedairconditioners–single-ducttypes 2.6

Packagedairconditioners–othertypes 2.6

Splitandmulti-splitairconditioners12kW 2.6

Splitandmulti-splitairconditioners12kW SCOP‘D’ratingformediantemperaturerangeinBSEN14825

Variablerefrigerantflowsystems 2.6

Vapourcompressioncyclechillers,watercooled750kW 3.9

Vapourcompressioncyclechillers,watercooled750kW 4.7

Vapourcompressioncyclechillers,aircooled750kW 2.55

Vapourcompressioncyclechillers,aircooled750kW 2.65

Waterloopheatpump 3.2

Absorptioncyclechillers 0.7

Gas-engine-drivenvariablerefrigerantflow 1.0

Air distribution systems

Specific fan power (SFP)10 (W/(l.s))

Newbuildings Existing buildings

Centralbalancedmechanicalventilationsystemwithheatingandcooling 1.6 2.2

Centralbalancedmechanicalventilationsystemwithheatingonly 1.5 1.8

Allothercentralbalancedmechanicalventilationsystems 1.1 1.6

Zonalsupplysystemwherefanisremotefromzone,suchasceilingvoidorroof-mountedunits

1.1 1.4

Zonalextractsystemwherefanisremotefromzone 0.5 0.5

Zonalsupplyandextractventilationunits,suchasceilingvoidorroofunitsservingasingleroomorzonewithheatingandheatrecovery

1.9 1.9

Localbalancedsupplyandextractventilationsystem,suchaswall/roofunitsservingsingleareawithheatingandheatrecovery

1.6 1.6

Localsupplyorextractventilationunitssuchaswindow/wall/roofunitsservingsinglearea(e.g.toiletextract)

0.3 0.4

Otherlocalventilationsupplyorextractunits 0.5 0.5

Fan-assistedterminalVAVunit 1.1 1.1

Fancoilunits(ratingweightedaverage) 0.5 0.5

Kitchenextract,fanremotefromzonewithgreasefilter 1.0 1.0

10 Maximumpressuredropisnotspecified.



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Air distribution systems: new and existing buildings Dry heat recovery efficiency

Plateheatexchanger 50%

Heatpipes 60%

Thermalwheel 65%

Runaroundcoil 45%

Internal lighting: option 1 Effective lighting efficacy

Generallightinginoffice,storageandindustrialareas 60luminairelumenspercircuit-watt

Generallightinginothertypesofspace 60lamplumenspercircuit-watt

Displaylighting 22lamplumenspercircuit-watt

Internal lighting: option 2 Lighting Energy Numeric Indicator (LENI)

Lightingsystem lightingenergylimit(kWh/m2/year)specifiedinTable44

Heating system circulators and water pumps Energy Efficiency Index

GlandlessstandalonecirculatorsGlandless,standaloneandintegratedcirculators

0.27until31July20150.23from1August2015

Waterpumps SeeSection13



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Section2:Gas,oilandbiomass-firedboilers

2.1 IntroductionThissectionprovidesguidanceonspecifyinggas,oilandbiomass-firedspaceheatingsystemsfornewandexistingbuildingstomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.Itcoversrelevantboilertypes,anddescribesmeasures,suchasadditionalcontrols,thatcanbeusedtogainheatingefficiencycreditstoimprovetheheatgeneratorseasonalefficiency.

2.2 ScopeofguidanceTheguidanceappliestowetcentralheatingsystemsusingcommercialboilersfiredby:

• naturalgas

• liquidpetroleumgas(LPG)

• oil,and

• biomass.

Theguidanceinthissectiondoesnotcover:

• steamboilers(astheseareusedprimarilyforprocessesratherthanprovisionofspaceheating),or

• electricboilers(forwhichseeSection7).

2.3 KeytermsTheterminologyusedtodescribeefficienciesforboilersystemsisdetailedbelow.Inthissectiontheheatgeneratorisaboiler.

Biomass means allmaterialofbiologicalorigin,excludingmaterialembeddedingeologicalformationsandtransformedtofossilfuel.

Boilerefficiency means theenergydeliveredbythewaterasitleavestheboiler(orboilersinmulti-boilerinstallations)tosupplytheheatemitters,dividedbytheenergy(basedongrosscalorificvalue)inthefueldeliveredtotheboiler,expressedasapercentage.Itisanexpressionoftheboiler’sperformanceandexcludesenergyusedbyboilerauxiliarycontrols,pumps,boilerroomventilationfans,mechanicalflueextractionfansandfandilutionsystems.TheboilerefficiencyismeasuredaccordingtothestandardsthatareusedtodemonstratecompliancewiththeBoilerEfficiencyDirective11.

Effectiveboilerseasonalefficiency istheboilerseasonalefficiency(ascalculatedbyEquation2belowforindividualboilers,orbyEquation3.1formultipleboilers),plusanyapplicableheatingefficiencycredits.

Economiser meansadevice,includingasecondaryheatexchangerfittedonorneartoaboiler,whichprovidesadditionalheattransfercapacity.Forthepurposesofthisguide,anyboilerwhichwillbesuppliedwithaneconomiser shouldhavetheeconomiserfittedwhentheboilerefficiencyistestedaccordingtothestandardsthatareusedtodemonstratecompliancewiththeBoilerEfficiencyDirective.Theeffectofthisontheboilerefficiencyat30%and100%oftheboileroutputmaybetakeninto

11 CouncilDirective92/42/EEC(theBoilerEfficiencyDirective)relatestotheefficiencyrequirementsfornewhotwaterboilersfiredwithliquidorgaseousfuels.TheassociatedUKlegislationistheBoiler(Efficiency)Regulations1993(SI1993/3083),amendedbytheBoiler(Efficiency)(Amendment)Regulations1994(SI1994/3083).



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Section 2: Gas, oil and biomass-fired boilers

accountinthevaluesusedforthecalculationoftheboilerseasonalefficiencyusingEquations2or3.1,orthethree-stepmethodandEquations3.2and3.3,asappropriate.

Condensingboiler means a boilerthatoffersahigherenergyefficiencybyrecoveringheatfromthefluegases.Thisisachievedbyincreasingtheheatexchangersurfacearea,whichrecoversextrasensibleheatwhenevertheboilerfires.Theboilerbecomesevenmoreefficientwhensystemwatertemperaturesarelowbecausethelargerheatexchangerareapromotescondensation,allowingmuchofthelatentheattoberecaptured.Standinglosses(whentheboilerisnotfiring)arelow,andpartloadperformanceisverygood.Inmultiple-boilersystems,condensingboilerscanbeusedastheleadboiler.

Standardboiler means, inthecontextofthisdocument,anon-condensingboiler.

Zonecontrol meansindependentcontrolofroomsorareaswithinbuildingsthatneedtobeheatedtodifferenttemperaturesatdifferenttimes.Whereseveralroomsorareasofabuildingbehaveinasimilarmanner,theycanbegroupedtogetherasa‘zone’andputonthesamecircuitandcontroller.

Sequencecontrol enablestwoormoreheatingboilerstobeswitchedonoroffinsequencewhentheheatingloadchanges.Thismaximisestheefficiencyoftheboilers,soreducingfuelconsumption,andreduceswearandtearontheboilers.

Directactingweathercompensation isatypeofcontrolthatenablesaheatgeneratortoworkatitsoptimumefficiency.Thecontrolallowstheboilertovaryitsoperatingflowtemperaturetosuittheexternaltemperatureconditionsandthetemperaturesinsidethebuilding.Weathercompensationreliesoncommunicationbetweenanexternalsensorandoneinsidetheboiler.Theboiler’swaterflowtemperatureisvariedaccordingly,sothatenergyisnotwastedbytheboilerturningonandoff.

Weathercompensationviaamixingvalve issimilartodirectactingweathercompensation,exceptthattheoutsidetemperatureisusedtocontrolthetemperatureofwatersuppliedtotheheatemittersbymixingtheboilerflowandreturnratherthanbyalteringtheboilertemperature.

Optimumstart isacontrolsystemoralgorithmwhichstartsplantoperationatthelatesttimepossibletoachievespecifiedconditionsatthestartoftheoccupancyperiod.

Optimiser isacontrolsystememployinganoptimumstartalgorithm.

Optimumstop isacontrolsystemoralgorithmwhichstopsplantoperationattheearliestpossibletimesuchthatinternalconditionswillnotdeterioratebeyondpresetlimitsbytheendoftheoccupancyperiod.

Two-stageburnercontrol isatypeofcontrolthatofferstwodistinctboilerfiringrates.

Multi-stageburnercontrol isatypeofcontrolthatoffersmorethantwodistinctfiringrates,butwithoutcontinuousadjustmentbetweenfiringrates.

Modulatingburnercontrol isatypeofcontrolthatprovidesa continuouslyvariablefiringrate,whichisalteredtomatchtheboilerloadoverthewholeturndownratio.

Decentralisation means thereplacementofcentralisedboilerplantanditsassociateddistributionpipeworkwithseveralsmaller,moreaccuratelysizedboilerplants,installedwithinoradjacenttothebuildingsorsystemstheyserve.Thiseliminateslongpiperunsbetweenbuildingsorthroughunheatedareas,soreducingheatlosses.

Buildingmanagementsystem(BMS) means abuilding-widenetworkwhichallowscommunicationwithandcontrolofitemsofHVACplant(andotherbuildingsystems)fromasinglecontrolcentre,whichmaybelocalorremote.Moreadvanced(‘full’)buildingmanagementsystemsofferawiderangeoffunctions,includingsequentialcontrol,zonecontrol,weathercompensation,frostprotectionandnightset-back,aswellasmonitoringandtargeting.



16


2.4DeterminingboilerseasonalefficiencySingle-boiler systems and multiple-boiler systems with identical boilers

Forboilerstherelevantheatgeneratorseasonalefficiencyistheboilerseasonalefficiency.Theboilerseasonalefficiencyisa‘weighted’averageoftheefficienciesoftheboilerat15%,30%and100%oftheboileroutput(theefficiencyat15%beingtakentobethesameasthatat30%).Thisisusuallyquotedbytheboilermanufacturer.NotethattheefficienciesbasedonnetcalorificvalueshouldbeconvertedtoefficienciesbasedongrosscalorificvalueusingtheappropriateconversionfactorinSAP2012TableE4.

Theboilerefficiencies,measuredat100%loadandat30%load,areusedinEquation2tocalculatetheboilerseasonalefficiency.TheweightingfactorsinEquation2reflecttypicalseasonaloperatingconditionsforaboiler.

Boilerseasonalefficiency0.8130%0.19

100% Equation 212

where:

30%

isthegrossboilerefficiencymeasuredat30%load

100%

isthegrossboilerefficiencymeasuredat100%load.

Equation2appliesto:

• single-boilersystemswheretheboileroutputis400kWandtheboilerwilloperateonalowtemperaturesystem

• multiple-boilersystemswhereallindividualboilershaveidenticalefficienciesandwheretheoutputofeachboileris400kWoperatingonlowtemperaturesystems.

Forboilerswithanoutput400kW,themanufacturer’sdeclaredefficienciesshouldbeused.

Multiple-boiler systems with non-identical boilers replacing existing systems

Wheremorethanoneboilerisinstalledonthesameheatingsystemandtheefficienciesoftheboilersarenotallidentical,Equation3.1shouldbeusedtocalculatetheoverallboilerseasonalefficiency.Allboilersshouldbeincludedinthecalculation,evenwhensomeareidentical.

Theboilerseasonalefficiencyformultiple-boilersystemswithnon-identicalboilersis:

OBSE =

S(BSE

R)Equation 3.1

SR

where:

OBSE

isthegrossoverallboilerseasonalefficiency,beinganaverageweightedbyboileroutputoftheindividualseasonalboilerefficiencies

BSE

isthegrossboilerseasonalefficiencyofeachindividualboilercalculatedusingEquation2

RistheratedoutputinkWofeachindividualboiler(at80/60°C).

12 Thisequationassumesthattheefficiencyat15%loadisthesameasat30%load(andtheequationhasbeensimplifiedaccordingly).



17


Multiple-boiler systems in new buildings

Inthecaseofmultipleboilersinnewbuildings,themoreaccuratethree-stepmethoddescribedbelowshouldbeusedtocalculatetheoverallseasonalboilerefficiency.Thesestepscanreadilybeprogrammedintoaspreadsheettoautomatethecalculation.

Step 1

Determinetheloadoneachboilerforeachofthethreesystempart-loadconditionsof15%,30%and100%.Forexample,ifthetotalsystemoutputismadeupofthreeequallysizedboilers,at15%ofsystemoutputtheleadboilerwillbeoperatingat45%ofitsratedoutput,withtheothertwoboilersswitchedoff.

Step 2

Determinetheefficiencyofeachboilerfortheaboveoperatingconditions.Intheaboveexample,theefficiencyoftheboileroperatingat45%canbedeterminedbylinearinterpolationbetweenitsefficienciesat30%and100%ofratedoutput.Whereitisnecessarytodeterminetheefficiencyofanindividualboilerat15%ofratedoutput,thisshouldbetakenasthesameastheefficiencyat30%ofratedoutput.(Notethattheefficiencyat15%ofratedoutputwillonlybeneededifasingleboilermeetsthefulldesignoutput.)

Step 3

Calculatetheoveralloperatingefficiencyateachofthesystempartloadconditionsusing:

pQ

p/S(q

b,p/

b,p) Equation 3.2

where:

pisthesystemefficiencyatpartloadconditionp,i.e.15%,30%and100%ofsystemratedoutput

Qpisthesystemheatoutputatpartloadconditionp

qb,p

istheindividualboilerheatoutputatsystempartloadconditionp

b,p

istheindividualboilerefficiencyatsystempartloadconditionp.

Calculatetheoverallboilerseasonalefficiencyastheweightedaverageoftheefficienciesatthethreeloadconditionsusing:

OBSE

0.3615%

0.4530%

0.19100%

Equation 3.3

Table2isaworksheetforfollowingthroughthesecalculations(usingmanufacturerdataforboilerefficiencyat100%and30%output).Table3showsacompletedexamplecalculationusingthisworksheet,forthecasewhereasystemwitharatedoutputof625kWisservedbythreeboilers,eachratedat250kW.Thefirsttwoboilersarecondensingboilers,whilethethirdisastandardboiler.Becausetheinstallationisoversized(750kWcomparedto625kW),atfullsystemoutputthefinalboilerisonlyoperatingat50%output(125/250).

Thenotesatthefootofthetableillustratehowthevariousvaluesarecalculated.



18


Table 2 Worksheet for calculating the overall boiler seasonal efficiency of a multiple-boiler system using the alternative three-step method

Boiler % efficiency at boiler outputs of

Boiler % output at system outputs of

Boiler % efficiency at system outputs of

Boiler no Rating kW 100% 30% 15% 30% 100% 15% 30% 100%

1

2

3

Systemefficiencyatpartload

Weightingfactor 0.36 0.45 0.19

Overallheatgeneratorseasonalefficiency

Table 3 Example calculation of the overall boiler seasonal efficiency of a multiple-boiler system in a new building

Boiler % efficiency at boiler outputs of

Boiler % output at system outputs of

Boiler % efficiency at system outputs of

Boiler no Rating kW 30% 100% 15% 30% 100% 15% 30% 100%

1 250 90% 86% 38.0% 75.0% 100.0% 89.6%[1] 87.4% 86.0%

2 250 90% 86% notfiring notfiring 100.0% notfiring notfiring 86.0%

3 250 85% 82% notfiring notfiring 50.0% notfiring notfiring 84.1%

Systemefficiencyatpartload 89.6% 87.4% 85.6%[2]

Weightingfactor 0.36 0.45 0.19

Overallheatgeneratorseasonalefficiency 87.9%[3]

Notes [1] Calculatedbylinearinterpolation

b,p

30%–(

30%–

100%)

(qb,p

–30%)

(100%–30%)

1,15%

30%

–(30%

–100%

)(38%–30%)

(100%–30%)

[2] Calculatedbydividingthethermaloutputofthesystem(625kW)bytherateoffuelconsumption,whichisgivenbythesumoftheboileroutputsdividedbytheirindividualoperatingefficiency,i.e.

100%

625

250100%

250100%

25050% =85.6%

86.0% 86.0% 84.1%

[3] Calculatedastheweightedaverage,i.e.

89.6%0.3687.4%0.4585.6%0.1987.9%



19


2.5 BoilersinnewbuildingsBackground

Newbuildingsshouldbeprovidedwithhighefficiencycondensingornon-condensingboilersthatmeettherecommendedminimumstandardsforheatgeneratorseasonalefficiencyinthisguide.

Commercialheatingsystemsareinherentlymorecomplicatedthandomesticsystemswithawiderrangeoftemperaturesandheatemitters.Theselectionofcondensingornon-condensingboilerswillbedeterminedbyapplicationandphysicalconstraints.

Note:Waterqualitycanhaveamajorimpactonsystemefficiency.Itisimportantthatdesignerstakeappropriatemeasurestoensurethatthesystemwaterisofgoodquality.

Condensingboilerswillmeetprojectedefficienciesonlywhentheyoperatewithasystemreturntemperaturebetween30°Cand40°Cfor80%oftheannualoperatinghours.Withareturntemperatureof55°Candabove,condensingboilerswillnotproducecondensateandwillhavesimilarefficienciestonon-condensinghighefficiencyboilers.Somesystemsaresuitableforweathercompensation,whichallowsreturntemperaturestofallintothecondensingrangeforsomeperiodsoftheheatingseason,andtheymaybebestservedbyamixtureofcondensingandnon-condensingboilers.

TheefficiencyvaluethatshouldbeenteredintoaccreditedNCMtoolstocalculatethecarbondioxideemissionrateistheeffectiveheatgeneratorseasonalefficiency.Forboilersinnewbuildings,noheatingefficiencycreditscanbegainedandtheeffectiveheatgeneratorseasonalefficiencyisthereforethesameastheheatgeneratorseasonalefficiency.

Recommended minimum standards

TomeetrelevantenergyefficiencyrequirementsintheBuildingRegulationswheninstallingboilerplantinnewbuildings:

a. whereasingleboilerisusedtomeettheheatdemand,itsboilerseasonalefficiency(grosscalorificvalue)calculatedusingEquation2shouldbenotlessthanthevalueinTable4

b. formultiple-boilersystems,theboilerseasonalefficiencyofeachboilershouldbenotlessthan82%(grosscalorificvalue),ascalculatedusingEquation2;andtheoverallboilerseasonalefficiencyofthemultiple-boilersystem,asdefinedbythethree-stepmethodandcalculatedusingEquations3.2and3.3,shouldbenotlessthanthevalueinTable4

c. therelevantminimumcontrolspackageinTable5shouldbeadopted.



20


Table 4 Recommended minimum heat generator seasonal efficiency for boiler systems in new buildings

Fuel type SystemBoiler seasonal efficiency(gross calorific value)

Naturalgas Single-boiler2MWoutput 91%

Single-boiler2MWoutput 86%

Multiple-boiler 82%foranyindividualboiler86%foroverallmulti-boilersystem

LPG Single-boiler2MWoutput 93%

Single-boiler2MWoutput 87%


Oil Single-boiler 84%


Table 5 Recommended minimum controls package for new boilers and multiple-boiler systems

Boiler plant output Package Minimum controls

100kW A a. Timingandtemperaturedemandcontrol,whichshouldbezonespecificwherethebuildingfloorareaisgreaterthan150m2.

b. Weathercompensationexceptwhereaconstanttemperaturesupplyisrequired.

100kWto500kW B a. ControlspackageAabove.b. Optimumstart/stopcontrolwitheithernightset-backorfrost

protectionoutsideoccupiedperiods.c. Two-stagehigh/lowfiringfacilityinboiler,ormultipleboilerswith

sequencecontroltoprovideefficientpart-loadperformance.

Note:Theheatlossfromnon-firingboilermodulesshouldbelimitedbydesignorapplication.Forboilersthatdonothavelowstandinglosses,itmaybenecessarytoinstallisolationvalvesordampers.

500kWindividualboilers C a. ControlspackageAandcontrolspackageB.b. Forgas-firedboilersandmulti-stageoil-firedboilers,fullymodulating

burnercontrols.

2.6BoilersinexistingbuildingsBackground

Boilerefficiencieshaveimprovedmarkedlyoverrecentyears.AmodernboilermeetingtheminimumrequirementsoftheBoilerEfficiencyDirectivehasaboilerseasonalefficiencyofapproximately78.5%(basedongrosscalorificvalue).

Thisguidancerecognisesthatinmanycasesusingcondensingboilertechnologyinexistingbuildingswouldbeeithertechnicallyimpractical(duetoflueingconstraints)oreconomicallyunviable.Forthisreasonnon-condensingboilersmaybeusedprovidedthattheymeettherecommendedminimumefficiencystandardsgiveninthissection.



21


Replacement boilers

TomeetrelevantenergyefficiencyrequirementsintheBuildingRegulationswheninstallingboilerplantinexistingbuildings:

a. theboilerseasonalefficiencyofeachboiler(inasingle-boilersystemoramultiple-boilersystemwithidenticalboilers)calculatedusingEquation2shouldbenotlessthanthevalueinTable6

b. formultiple-boilersystemsusingnon-identicalboilers,theoverallboilerseasonalefficiencycalculatedusingEquation3.1shouldbenotlessthanthevalueinTable6

c. thecontrolspackageinTable7shouldbeadopted–i.e.zonecontrol,demandcontrolandtimecontrol

d. theeffectiveboilerseasonalefficiencyshouldbenotlessthanthevalueinTable6.Tomeetthestandard,itmaybenecessarytoadoptadditionalmeasuresfromTable8inordertogainheatingefficiencycredits(seebelow).

Table 6 Recommended minimum heat generator seasonal efficiency for boiler systems in existing buildings

Fuel typeEffective boiler seasonal efficiency(gross calorific value)

Boiler seasonal efficiency(gross calorific value)

Naturalgas 84% 82%

LPG 85% 83%

Oil 86% 84%

Table 7 Recommended minimum controls package for replacement boilers in existing buildings

Minimum controls package Suitable controls

a. Zonecontrol Zonecontrolisrequiredonlyforbuildingswherethefloorareaisgreaterthan150m2.Asaminimum,on/offcontrol(e.g.throughanisolationvalveforunoccupiedzones)shouldbeprovided.

b. Demandcontrol Roomthermostatwhichcontrolsthroughadivertervalvewithconstantboilerflowwatertemperature.Thismethodofcontrolisnotsuitableforcondensingboilers.

c. Timecontrol Timeclockcontrols.

2.7 HeatingefficiencycreditsforreplacementboilersWheretheboilerseasonalefficiencyislessthantheminimumeffectiveboilerseasonalefficiencyforthattypeofboiler,additionalmeasures willneedtobeadoptedtoachievetheminimumeffectiveheatgeneratorseasonalefficiencyinTable6.

Table8indicatesthemeasuresthatmaybeadoptedandtherelevantheatingefficiencycreditsthatareapplicable.Itshouldbenotedthatthemaximumnumberofheatingefficiencycreditsthatcanbeclaimedis4percentagepoints.



22


13 Themaximumthatcanbeclaimedis4points.

Table 8 Heating efficiency credits for measures applicable to boiler replacement in existing buildings

Measure

Heating efficiency credits(%points)13 Comments

A Boileroversize20% 2 Boileroversizeisdefinedastheamountbywhichthemaximumboilerheatoutputexceedsthesystemheatoutputatdesignconditions,expressedasapercentageofthatsystemheatoutput.Formultiple-boilersystemsthemaximumboilerheatoutputisthesumofthemaximumoutputsofalltheboilersinthesystem.

B Multipleboilers 1 Wheremorethanoneboilerisusedtomeettheheatload.

C Sequentialcontrolofmultiple-boilersystems

1 Appliesonlytomultiple-boiler/modulearrangements.Itisrecommendedthatthemostefficientboilershouldactastheleadinamultiple-boilersystem.

D Monitoringandtargeting 1 Meansofidentifyingchangesinoperationoronsetoffaults.Thecreditcanonlybeclaimedifmeteringisincludedandaschemefordatacollectionisprovidedandavailableforinspection.

E i.Thermostaticradiatorvalves(TRVs)alone.Wouldalsoapplytofannedconvectorsystems

1 TRVsenablethebuildingtemperaturetobecontrolledandthereforereducewasteofenergy.

ii.Weather(inside/outsidetemperature)compensationsystemusingamixingvalve

1.5 Providesmoreaccuratepredictionofloadandhencecontrol.

iii.AdditionofTRVortemperaturezonecontroltoiiabovetoensurefullbuildingtemperaturecontrol

1 ThiscreditisadditionaltoEiiabove.

F i.A‘room’thermostatorsensorthatcontrolsboilerwatertemperatureinrelationtoheatload

0.5

ii.Weather(inside/outsidetemperature)compensationsystemthatisdirectacting

2 Providesmoreaccuratepredictionofloadandhencecontrol.

iii.AdditionofTRVortemperaturezonecontroltoioriiabovetoensurefullbuildingtemperaturecontrol

1 ThiscreditisadditionaltoFiorFiiabove.NoteFiandFiiarenotusedtogether.



23


Table 8 Heating efficiency credits for measures applicable to boiler replacement in existing buildings (continued)

Measure

Heating efficiency credits(%points)13 Comments

G i.Optimumstart 1.5 Acontrolsystemwhichstartsplantoperationatthelatesttimepossibletoachievespecifiedconditionsatthestartoftheoccupancyperiod.

ii.Optimumstop 0.5 Acontrolsystemwhichstopsplantoperationattheearliestpossibletimesuchthatinternalconditionswillnotdeterioratebeyondpresetlimitsbytheendoftheoccupancyperiod.

iii.Optimumstart/stop 2 Acontrolsystemwhichstartsplantoperationatthelatesttimepossibletoachievespecifiedconditionsatthestartoftheoccupancyperiodandstopsplantoperationattheearliestpossibletimesuchthatinternalconditionswillnotdeterioratebeyondpresetlimitsbytheendoftheoccupancyperiod.Notethatifoptimumstart/stopsystemsareinstalled,creditsGiandGiicannotalsobeclaimed.

H Fullzonedtimecontrol 1 Allowingeachzonetooperateindependentlyintermsofstart/stoptime.Onlyapplicablewhereoperationalconditionschangeindifferentzones.Doesnotincludelocaltemperaturecontrol.

I Fullbuildingmanagementsystem(BMS)

4 AfullBMSlinkedtotheheatingplantwillprovide:sequentialcontrolofmultipleboilers,fullzonedtimecontrolandweathercompensationwhereapplicable;frostprotectionornightset-back;optimisationandmonitoringandtargeting.NotethatifafullBMSisinstalled,nofurtherheatingefficiencycreditscanbeclaimed.

J Decentralisedheatingsystem 1 Eliminationoflongpiperunsbetweenbuildingsorthroughunheatedareasinbuildingsinordertoreduceexcessiveheatlosses.

Example: Usingheatingefficiencycredits toachievethe minimumeffectiveheatgeneratorseasonalefficiencyforaboilersysteminanexistingbuilding

Anexistingboileristobereplacedwithagasboilerwithaboilerseasonalefficiencyof82%,theminimumallowedbyTable6.

Theboiler’seffectiveboilerseasonalefficiencyneedstobeatleast84%accordingtoTable6,whichmeansthat2percentagepointsofheatingefficiencycreditsareneeded.

Thefollowingapproachwouldachievethis:

a. restrictboileroversizingto15%(afteradetailedassessmentofload)

b. fitaroomthermostattocontrolboilerwatertemperatureinrelationtoheatload



24


c. usetwoequallysizedboilerstomeettheheatloadinplaceoftheexistingsingleboiler

d. fitTRVstocontrolthetemperatureinareasotherthanwheretheroomthermostatisfitted.

Table9belowshowshowcreditswouldbeawardedinthisexample.

Table 9 Example to illustrate allocation of heating efficiency credits for a replacement boiler in an existing building

Plant descriptionHeating efficiency credits(%points)

Boileroversizingislessthan20% 2

Systemcontrolledbyroomthermostatwhichcontrolsboilerwatertemperature 0.5

SystemusesTRVstoensurefullbuildingtemperaturecontrol 1

Multipleboilers 1

Total credits 4.5

Effectiveboilerseasonalefficiency

=boilerseasonalefficiencymaximumof4heatingefficiencycredits

=82486%

Inthisexampletheminimumeffectiveboilerseasonalefficiencyof84%isexceededby2percentagepoints.

2.8BiomassboilersBackground

ThemethodinSection2.4forcalculatingtheseasonalefficiencyofsingleandmultipleboilersfiredbygas,LPGandoilisnotappropriateforbiomassboilers.

Forbiomassboilers,requirementsandtestmethodsarecoveredbyBSEN12809:2001+A1:2004Residential independent boilers fired by solid fuel. Nominal heat output up to 50 kW. Requirements and test methods.

Recommended minimum standards

TomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations:

a. theefficiencyofbiomassboilersattheirnominalloadshouldbeatleast:

i. 65%forindependentgravity-fedboilers20.5kW

ii. 75%forindependentautomaticpellet/woodchipboilers

b. controlsasforgas,LPGandoilboilersinTable5shouldbeprovided,wheretechnicallyfeasible.



25

Section 3: Heat pumps

Section3:Heatpumps

3.1 IntroductionThissectiongivesguidanceonspecifyingheatpumpstoprovidespaceheatinganddomestichotwaterinnewandexistingbuildingstomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.

Theheatpumpscoveredinthissectiontakeheatenergyfromalowtemperaturesourceandupgradeittoahighertemperatureatwhichitcanbeusefullyemployedforheating.

Theguidancecoversmeasures,suchasadditionalcontrols,thatcanbeusedtogainheatingefficiencycreditstoimprovethecoefficientofperformanceofheatpumps.

Forguidanceonreversecycleheatpumpsthatalsoprovidecooling,seeSection9ofthisguide.

3.2 ScopeofguidanceTheguidanceinthissectionappliestothecommercialheatpumpsystemsidentifiedinTable10,whichcategorisesthedifferenttypesofheatpumpaccordingto:• thesourceoftheheat• themediumbywhichitisdelivered,and• thetechnology.

Table 10 Heat pump types and associated test standards

Heat pump type Technology Sub-technology Test standard

Electrically-driven warm air

Ground-to-air

Singlepackagevariablerefrigerantflowwarmairsystems ISO13256-114

Energytransfersystems(matchingheating/coolingdemandsinbuildings)

Water-to-air

Singlepackagevariablerefrigerantflowwarmairsystems BSEN14511-315

Energytransfersystems(matchingheating/coolingdemandsinbuildings)

Air-to-air Singlepackage BSEN14511-3

Splitsystem

Multi-splitsystem

Variablerefrigerantflowsystems

Electrically-driven warm water

Ground-to-water

Singlepackagevariablerefrigerantflowwarmairsystems ISO13256-216

Splitpackage

Water-to-water

Singlepackagevariablerefrigerantflowwarmairsystems BSEN14511-3

Splitpackage

Air-to-water

Singlepackage BSEN14511-3

Splitpackagevariablerefrigerantflowwarmairsystems

Gas-engine-driven

Availableasvariablerefrigerantflowwarmairsystems GenerallytoBSEN14511-3

14 ISO13256-1Water-source heat pumps. Testing and rating for performance. Part 1: Water-to-air and brine-to-air heat pumps.15 BSEN14511-3:2013Air conditioners, liquid chilling packages and heat pumps with electrically driven compressors for space heating and cooling. Test methods.16 ISO13256-2Water-source heat pumps. Testing and rating for performance. Part 2: Water-to-water and brine-to-water heat pumps.



26


3.3 KeytermsCoefficientofperformance(COP)isameasureoftheefficiencyofaheatpumpatspecifiedsourceandsinktemperatures,butmaynotaccuratelyrepresentinstalledperformance:

HeatingCOPheatoutput/powerinput Equation 4

%COP(COP100)istheheatgeneratorefficiency.

Effective%COPisthe%COPwithheatingefficiencycredits.

TheCOPofaheatpumpshouldbedeterminedinaccordancewiththeappropriateteststandardidentifiedinTable10.Theinputpoweritemstobeincludedinthecalculationaredefinedinthestandard.

Seasonalcoefficientofperformance(SCOP) istheoverallcoefficientofperformanceoftheunitforthedesignatedheatingseason.Itmakesgeneralassumptionsabouttheamountofauxiliaryheatingneededtotopupthespaceandwaterheatingavailablefromtheheatpump.

SCOPismeasuredinaccordancewiththeproceduresinBSEN14825:2013Air conditioners, liquid chilling packages and heat pumps with electrically driven compressors for space heating and cooling. Testing and rating at part load conditions and calculation of seasonal performance.

TheNationalCalculationMethodologyforcalculatingcarbondioxideemissionratesfrombuildingsusesSCOP.

Seasonalperformancefactor(SPF)isanothermeasureoftheoperatingperformanceofanelectricheatpumpovertheseason.Itistheratiooftheheatdeliveredtothetotalelectricalenergysuppliedovertheseason,butthereareuptosevendifferentwaystodrawthesystemboundaries.Forexample,SPFH2

excludesauxiliaryresistanceheatingwhileSPF

H4includesit–makingalargedifference.

SAP2012calculations(fordwellings)useSPF–eithermeasuredvaluesforproductslistedintheProductCharacteristicsDatabase,orthedefaultvaluesinTable4aforproductsnotlistedthere.

TheMicrogenerationCertificationSchemeinstallationstandard,MIS3005,usesSPFtocalculatesystemperformance(althoughtheheatpumpproductstandard,MCS007,currentlyspecifiesaminimumCOP).

Seasonalprimaryenergyefficiencyratio(SPEER)isanemergingratingfigurereflectingtheuseofprimaryenergyforalltypesofheatpump,fossilfuelboilerandgas-drivencogenerationtechnologies,aswellashybridsystemswheresolarheatingoraheatpumpisbackedupwithelectricheatingorafossilfuelboiler.

EnergylabellingwiththeSPEERwillbemandatoryfrom2015undertheEnergyLabellingDirective.TestingandratingwillbeinaccordancewithBSEN14825,asforSCOP.

3.4 HeatpumpsinnewandexistingbuildingsAtthetimeofpreparationofthisguide,EuropeanCommissionRegulationNo206/2012setsstandardsonlyfortheSCOPofelectrically-drivenair-to-airheatpumpswithanoutput12kW.TherearecurrentlynoEuropeanteststandardsforpart-loadtestingofair-to-airheatpumpswithanoutput12kWorforothertypesofheatpump17,andsotheperformanceofthesemustbespecifiedusingCOPobtainedattheheatingsystemratingconditions.

17 Requirementsforheatpumpsdeliveringwaterwithanoutputupto400kWareexpectedtocomeintoforceinAugust2015.



27


Thecurrentrecommendationsinthisguidearethatheatpumpsinnewandexistingbuildingsshould:

a. ifair-to-airwithanoutput12kW,haveatleastaSCOP‘D’ratingforthemediantemperaturerangeinBSEN14825

b. orelsehaveaCOPwhichisnotlessthanthevalueinTable11

c. featureasaminimumthecontrolspackageinTable12.

Table 11 Recommended minimum COP for heat pumps in new and existing buildings

Heat pump type Minimum COP at the rating conditions18

Alltypes(exceptair-to-airwithoutput12kW,absorptionandgas-engine)forspaceheating

2.5

Alltypes(exceptabsorptionandgas-engine)fordomestichotwaterheating

2.0

Absorption 0.5

Gas-engine 1.0

Fornon-residentialbuildings,theheatpumpsystemcanbesizedtomeeteitherthefullheatingandhotwaterdemandorpartofit.Economicallyviableinstallationsprovideatleast50%oftheheatingandhotwaterdemandforthebuilding.

Table 12 Recommended minimum controls package for heat pump systems in new and existing buildings

Heat source/sink Technology Minimum controls package

Alltypes Alltechnologies

A a. On/offzonecontrol.Iftheunitservesasinglezone,andforbuildingswithafloorareaof150m2orless,theminimumrequirementisachievedbydefault.

b. Timecontrol.

Air-to-air Singlepackage

Splitsystem

Multi-splitsystem

Variablerefrigerantflowsystem

B a. ControlspackageAabove.b. Heatpumpunitcontrolsfor:

i. controlofroomairtemperature(ifnotprovidedexternally)ii. controlofoutdoorfanoperationiii. defrostcontrolofexternalairsideheatexchangeriv. controlforsecondaryheating(iffitted).

c. Externalroomthermostat(ifnotprovidedintheheatpumpunit)toregulatethespacetemperatureandinterlockedwiththeheatpumpunitoperation.

18 RatingconditionsarestandardisedconditionsfordeterminingperformancespecifiedinBSEN14511:2013Air conditioners, liquid chilling packages and heat pumps with electrically driven compressors for space heating and cooling.



28


Table 12 Recommended minimum controls package for heat pump systems in new and existing buildings (continued)

Heat source/sink Technology Minimum controls package

Water-to-airGround-to-air

Singlepackageenergytransfersystems(matchingheating/coolingdemandinbuildings)

D a. ControlspackageAabove.b. Heatpumpunitcontrolsfor:

i. controlofroomairtemperature(ifnotprovidedexternally)ii. controlofoutdoorfanoperationforcoolingtowerordrycooler

(energytransfersystems)iii. controlforsecondaryheating(iffitted)onair-to-airsystemsiv. controlofexternalwaterpumpoperation.


Air-to-waterWater-to-waterGround-to-water

Singlepackage

Splitpackage

E a. ControlspackageAabove.b. Heatpumpunitcontrolsfor:

i. controlofwaterpumpoperation(internalandexternalasappropriate)ii. controlofwatertemperatureforthedistributionsystemiii. controlofoutdoorfanoperationforair-to-waterunitsiv. defrostcontrolofexternalairsideheatexchangerforair-to-watersystems.


Gas-engine-drivenheatpumpsarecurrentlyavailableonlyasvariablerefrigerantflowwarmairsystems

Multi-split

Variablerefrigerantflow

F a. ControlspackageAabove.b. Heatpumpunitcontrolsfor:

i. controlofroomairtemperature(ifnotprovidedexternally)ii. controlofoutdoorfanoperationiii. defrostcontrolofexternalairsideheatexchangeriv. controlforsecondaryheating(iffitted).


3.5 HeatingefficiencycreditsforheatpumpsystemsinexistingbuildingsHeatingefficiencycreditscanbegainedforheatpumpsystemsinstalledinexistingbuildingsbyadoptingtheadditionalmeasuresinTable13.Thesecreditsareaddedtothe%COPtoproducetheeffective%COP.

Table 13 Heating efficiency credits for additional measures applicable to heat pump systems in existing buildings

Measure Heating efficiency credits (%points) Comments

20%oversizing 2 Theamountbywhichthemaximumheatpumpoutputexceedsthesystemheatoutputatdesignconditions,expressedasapercentageofthatsystemheatoutput.

Optimumstop 2 Acontrolsystemwhichstopsplantoperationattheearliestpossibletimesuchthatinternalconditionswillnotdeterioratebeyondpresetlimitsbytheendoftheoccupancyperiod.

Fullzonecontrol 2 Allowseachzonetooperateindependentlyintermsofstart/stoptime.Onlyappropriatewhereoperationalconditionschangeindifferentzones.

Monitoringandtargeting 2 Meansofidentifyingchangesinoperationoronsetoffaults.



29


Example: Usingheatingefficiencycreditstoachievetherecommendedstandardforeffective%COPforaheatpumpinstallation

Aproposedsystemhasanair-to-water,electrically-drivenheatpumpsupplyingheattoanunderfloorheatingsystem.TheCOPoftheheatpumptestedtoBSEN14511is2.46,whichisbelowtheminimumstandardrecommendedbyTable11forspaceheating.

TheminimumcontrolspackagerecommendedbyTable12ispackageE,comprising:

a. zonecontrolandtimecontrol

b. heatpumpunitcontrolsfor:

i. controlofoutdoorfanoperationforcoolingtowerordrycooler(energytransfersystems)

ii. controlofexternalwaterpumpoperationandwatertemperatureforthedistributionsystem

c. roomthermostattoregulatethespacetemperatureandinterlockedwiththeheatpumpunitoperation.

Table14showstheheatingefficiencycreditsthatcanbegainedbyaddingoptimumstopcontrolandfullzonecontrol.

Effective%COP%COPheatingefficiencycredits2464250%

TheeffectiveCOPistherefore2.50,whichmeetstheminimumrequiredbyTable11.

Table 14 Example to illustrate the allocation of heating efficiency credits to a new heat pump system in an existing building

Measure Heating efficiency credits (%points)

MeasuresspecifiedincontrolspackageA 0(asthisistheminimumstandard)

MeasuresspecifiedincontrolspackageE 0(asthisistheminimumstandard)

Optimumstop 2

Fullzonecontrol 2

Total credits 4



30


3.6 Supplementaryinformation

Heat source/sink Technology Comments

Air-to-air Singlepackage Unitsmaybeductedononeorotherofthesupplyandreturnairsidesorductedonbothsides.Ductingneedstobedesignedtotakeintoaccountthemaximumspecificfanpowerallowable(seeSection10ofthisguide)andtomaintaintheminimumallowablecoefficientofperformance.

Split

Multi-split

Variablerefrigerantflow

Gas-engine-driven

Asplitsystemwillcompriseasingleoutdoorunitandasingleindoorunitasapackage.Multi-splitandvariablerefrigerantflowsystemswillcompriseasingleoutdoorunitandtwoormoreindoorunitsasapackage.Severalpackagesmaybeusedtosatisfytherequirementsofthebuilding.

Inorderforefficienciestobemaintained,allconnectingpipeworkshouldbeinstalledinaccordancewithmanufacturers’recommendations(diameter,length,insulationandriserheight).Anyductingshouldbedesignedtotakeintoaccountthemaximumspecificfanpowerallowableandtomaintaintheminimumallowablecoefficientofperformance.

Water-to-air

Ground-to-air

Singlepackage

Energytransfer

Energytransfersystemsgenerallyconsistofmultiplewater-sourceheatpumpsconnectedinparalleltoacommonclosedwaterloop.Theyareinstalledtooffsetthesimultaneousheatingandcoolingdemandinabuildingduetothedifferentloadspresentontheaspectsofthebuilding.Watercirculationpumpsfortheclosedloopshouldbetakenintoconsiderationalongwiththefanpowerrequiredforthecoolingtowerordrycoolerorenergyforwaterpumpsforthegroundloopifthismethodisutilisedforheatinjectionandrejection.Anyductingshouldbedesignedtotakeintoaccountthemaximumspecificfanpowerallowableandtomaintaintheminimumallowablecoefficientofperformance.

Air-to-water

Water-to-ground

Water-to-water

Singlepackage

Splitpackage

Watercirculationpumpsforthedeliveryofheatedwatertothebuildingalongwiththeenergyofwaterpumpsusedfortheheatsource(waterorground)shouldbeconsideredinthecalculation.Anyductingshouldbedesignedtotakeintoaccountthemaximumspecificfanpowerallowableandtomaintaintheminimumallowablecoefficientofperformance.

AdditionalguidanceondesigncriteriaforheatingsystemswithintegratedheatpumpsisgiveninBSEN15450:2007 Heating systems in buildings. Design of heat pump heating systems.



31

Section 4: Gas and oil-fired warm air heaters

Section4:Gasandoil-firedwarmairheaters

4.1 IntroductionThissectiongivesguidanceonspecifyinggasandoil-firedwarmairheatersforspaceheatinginnewandexistingbuildingstomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.Itincludesguidanceonmeasures,suchasadditionalcontrols,thatcanbeusedtogainheatingefficiencycreditstoimprovetheheatgeneratorseasonalefficiency.

4.2ScopeofguidanceTheguidanceinthissectioncoversthewarmairheaterslistedinTable15.Theguidancealsocoversindirectgasoroil-firedheatexchangers(asusedinlargeductedsystemsforofficeblocks,shoppingandleisurecomplexes,etc.)toprovideheatingandfreshorconditionedair.WarmaircentralheatingsystemsarenotwithinthescopeofthissectionbutarecoveredintherelevantheatgeneratorsectionandSection10Air distribution.

Table 15 Warm air heaters and test methods

Type of warm air heater Product standard

Type1 Gas-firedforcedconvectionwithoutafantoassisttransportationofcombustionairand/orcombustionproducts

BSEN621:200919

Type2 Gas-firedforcedconvectionincorporatingafantoassisttransportationofcombustionairand/orcombustionproducts

BSEN1020:200920

Type3 Directgas-firedforcedconvection BSEN525:200921

Type4 Oil-firedforcedconvection BSEN13842:200422

4.3 KeytermsHeatgeneratorseasonalefficiencyofairheaters,sincetheyoperateunderthesameconditionsatalltimes,isequivalenttotheirmeasuredsteadystatethermalefficiency(netcalorificvalue),whichcanbeobtainedfromtheheatermanufacturer’sdataandconvertedtoefficiency(grosscalorificvalue)usingtheconversionfactorsinSAP2012TableE4.

Forindirect-firedheaters,datavaluesforheatoutputandnetheatinputaremeasuredusingtheefficiencytestmethodsdescribedinBSEN1020,BSEN621orBSEN13842asappropriate.

Fordirect-firedheaters,theefficiencyshouldbecalculatedusingthemethoddescribedinBSEN525.19202122

19 BSEN621:2009Non-domestic gas-fired forced convection air heaters for space heating not exceeding a net heat input of 300 kW, without a fan to assist transportation of combustion air and/or combustion products.

20 BSEN1020:2009Non-domestic forced convection gas-fired air heaters for space heating not exceeding a net heat input of 300 kW, incorporating a fan to assist transportation of combustion air or combustion products.

21 BSEN525:2009Non-domestic direct gas-fired forced convection air heaters for space heating not exceeding a net heat input of 300 kW.22 BSEN13842:2004Oil-fired convection air heaters. Stationary and transportable for space heating.



32


Thecalculationofthethermalefficiency(net)should:

• takeaccountoftheheaterandtheexhaustchimneywithinthebuildingenvelope

• excludefans.

Effectiveheatgeneratorseasonalefficiencyistheheatgeneratorseasonalefficiencywithaddedheatingefficiencycredits(seebelow).ItisthevalueenteredintoNCMtoolssuchasSBEMtocalculatethebuildingcarbondioxideemissionrate(BER).

4.4WarmairheatersinnewandexistingbuildingsWarmairsystemsinnewandexistingbuildingsshouldhave:

a. aneffectiveheatgeneratorseasonalefficiencywhichisnoworsethaninTable16

b. acontrolspackagefeaturing,asaminimum,timecontrol,spacetemperaturecontroland,whereappropriateforbuildingswithafloorareagreaterthan150m2,zonecontrol.

Table 16 Recommended minimum effective heat generator seasonal efficiency

Warm air heater type (seeTable15)Effective heat generator seasonal efficiency(net calorific value)

Types1,2naturalgas 91%

Types1,2LPG 91%

Type3* 100%

Type4 91%

*ForType3airheaters,100%ofthenetheatinputisdeliveredtothespace.SpecificventilationrequirementsasdefinedinBSEN525shouldbemet.

4.5 HeatingefficiencycreditsforwarmairheatersinnewandexistingbuildingsHeatingefficiencycreditscanbegainedbyadoptingtheadditionalmeasureslistedinTable17.

Table 17 Heating efficiency credits for additional measures applicable to warm air heaters

Measure

Heating efficiency credits(%points) Comments


Hi/Loburners 2 Two-stageburnerswhichenabletwodistinctfiringrates.

Modulatingburners 3 Burnercontrolswhichallowcontinuousadjustmentofthefiringrate.



33

Section 4: Gas and oil-fired warm air heaters

Destratification fans and air-induction schemes

Itisrecognisedthatdestratificationfansandair-inductionschemesmayimprovetheefficiencyofawarmairsystemandsignificantlyreducethecarbonemissionsassociatedwiththeheatingsystem.ThebenefitsofthesemeasuresarealreadytakenintoaccountbytheNCMsonoheatingefficiencycreditscanbegainedbyusingthem.Notethatwarmairsystemswithairinductionschemesordestratificationfansshouldnotbeconfusedwithcentralheatingsystemsthathaveairdistribution.

Example: Usingheatingefficiencycreditstoexceedtheminimumeffectiveheatgeneratorseasonalefficiencyforawarmairheater

Aproposedbuildinghasagas-firedforced-convectionwarmairheaterwithoutafantoassisttransportationofcombustionairorcombustionproducts.WhentestedtoBSEN621:2009thethermalefficiency(netcalorificvalue)isfoundtobe91%,whichmeetstheminimumeffectiveheatgeneratingefficiencyrecommendedforthistypeofsysteminTable16.

Theminimumcontrolspackagespecifiedinparagraph4.4bcompriseszone,spacetemperatureandtimecontrols.Table18showshowcreditsareawardedbyaddingoptimumstopcontrol,modulatingburnersanddestratificationfans.

Table 18 Example to illustrate the allocation of heating efficiency credits to a warm airheater system


Zone,spaceandtemperaturecontrols 0(asthisistheminimumstandard)

Modulatingburners 3

Optimumstop 1

Destratificationfans 0(asthebenefitsarealreadyrecognisedbytheNCM)

Total credits 4

Effectiveheatgeneratorseasonalefficiencynetthermalefficiencyheatingefficiencycredits

91495%

Theeffectiveheatgeneratorseasonalefficiencyistherefore95%,exceedingtheminimumstandardby4percentagepoints.ThevaluethatshouldbeenteredintotheaccreditedNCMtooltocalculatethecarbondioxideemissionrateis95%.



34


Section5:Gasandoil-firedradiantheaters

5.1 IntroductionThissectiongivesguidanceonspecifyingradiantheatersforspaceheatinginnewandexistingbuildingstomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.Itincludesguidanceonmeasures,suchasadditionalcontrols,thatcanbeusedtogainheatingefficiencycreditstoimprovetheheatgeneratorseasonalefficiency.

5.2 ScopeofguidanceTheguidanceinthissectioncoversthetypesofradiantheaterlistedinTable19.

Table 19 Types of radiant heater and associated product standards

Radiant heater type Product standard

Luminousradiantheater BSEN419-1:200923

Non-luminousradiantheater BSEN416-1:200924

Multi-burnerradiantheater BSEN777series25

Oil-firedradiantheater N/A

5.3 KeytermsRadiantheaterseasonalefficiency(heatgeneratorseasonalefficiency)isequivalenttothermalefficiency(netcalorificvalue).232425Forfluedappliances,themanufactureroftheradiantheatershoulddeclareathermalefficiencymeasuredtotheteststandardsBSEN102026orBSEN1384227asapplicable.

Thecalculationofthethermalefficiency(netcalorificvalue)should:

a. takeaccountoftheradiantheaterandassociatedfluepipe/tailpipewithinthebuildingenvelope

b. excludefans.

23 BSEN419-1:2009Non-domestic gas-fired overhead luminous radiant heaters. Safety. 24 BSEN416-1:2009Single-burner gas-fired overhead radiant tube heaters. Safety. 25 BSEN777-1:2009Multi-burner gas-fired overhead radiant tube heater systems for non-domestic use. System D. Safety.

BSEN777-2:2009Multi-burner gas-fired overhead radiant tube heater systems for non-domestic use. System E. Safety. BSEN777-3:2009Multi-burner gas-fired overhead radiant tube heater systems for non-domestic use. System F. Safety. BSEN777-4:2009Multi-burner gas-fired overhead radiant tube heater systems for non-domestic use. System H. Safety.

26 BSEN1020:2009Non-domestic forced convection gas-fired air heaters for space heating not exceeding a net heat input of 300 kW, incorporating a fan to assist transportation of combustion air or combustion products.

27 BSEN13842:2004Oil-fired convection air heaters. Stationary and transportable for space heating.



35

Section 5: Gas and oil-fired radiant heaters

5.4 RadiantheatersRadiantheatersinnewandexistingbuildingsshouldhave:

a. aneffectiveheatgeneratorseasonalefficiencynotworsethaninTable20

b. acontrolspackageconsistingof,asaminimum,timecontrolandspacetemperaturecontrolwithblackbulbsensors.

Table 20 Recommended minimum performance standards for radiant heaters

Appliance type

Effective heat generator seasonal efficiency

Thermal Radiant

Luminousradiantheater–unflued 86% 55%

Non-luminousradiantheater–unflued 86% 55%

Non-luminousradiantheater–flued 86% 55%

Multi-burnerradiantheater 91% N/A

5.5 HeatingefficiencycreditsforradiantheatersinexistingbuildingsHeatingefficiencycreditscanbegainedbyadoptingtheadditionalmeasureslistedinTable21.Theyareaddedtotheheatgeneratorseasonalefficiency(thethermalefficiency–netcalorificvalue)togivetheeffectiveheatgeneratorseasonalefficiency.

Table 21 Heating efficiency credits for additional measures applicable to radiant heaters

MeasureHeating efficiency credits(%points) Comments

Controls(additionaltotheminimumpackage)


Optimumstart 0.5 Acontrolsystemwhichstartsplantoperationatthelatestpossibletimesuchthatinternalconditionswillbeuptorequiredlimitsatthestartoftheoccupancyperiod.

Zonecontrol 1 Acontrolsysteminwhicheachzoneoperatesindependentlyintermsofstart/stoptime.Itisonlyappropriatewhereoperationalconditionschangeindifferentzones.



36


Example: Usingheatingefficiencycreditstoachievetheminimumeffectiveheatgeneratorseasonalefficiencyforaradiantheatersystem

Aproposedbuildingwillhaveafluednon-luminousradiantheatersystemwithathermalefficiency(heatgeneratorseasonalefficiency)of84%.Ablackbulbsensorandanoptimiserwillbefitted.

Theheatingefficiencycreditsassociatedwiththesemeasuresareaddedtotheappliancethermalefficiencytoobtaintheeffectiveheatgeneratorseasonalefficiency.

Table22showshowcreditsareawardedforthisexample.

Table 22 Example to illustrate the allocation of heating efficiency credits to a radiantheater system


Blackbulbsensor 0(asminimumrequirement)

Optimumstop 1

Zonecontrol 1

Total credits 2

Effectiveheatgeneratorseasonalefficiencythermalefficiencyheatingefficiencycredits

84286%

Inthisexample,theapplicationofadditionalmeasurestogainheatingefficiencycreditshasbroughttheradiantheater’seffectiveheatgeneratorseasonalefficiencyuptotheminimumrecommendedvalue.



37

Section 6: Combined heat and power and community heating

Section6:Combinedheatandpowerandcommunityheating

6.1 IntroductionThissectiongivesguidanceonspecifyingcombinedheatandpower(CHP)systemsforspaceheating,hotwaterandchilledwater(viaabsorptionchillers)innewandexistingbuildingstomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.GuidanceonthedesignofcommunityheatingsystemscanbefoundinSection6oftheDomestic Building Services Compliance Guide.

CHPunitsarenormallyusedinconjunctionwithboilers.ThemajorityoftheannualheatdemandisusuallyprovidedbytheCHPplant,whiletheboilersareusedtomeetpeakdemandandinperiodswhentheCHPunitisnotoperating(forexampleatnightorwhenundergoingmaintenance).

CHPunitsmayonarelativelysmallscalesupplysinglebuildings,oronalargerscalesupplyanumberofbuildingsthroughacommunityheatingsystem.Themostcommonfuelisnaturalgas,whichcanbeusedinspark-ignitiongasengines,micro-turbines,orgasturbinesinopencycleorcombinedcycle.

6.2ScopeofguidanceTheguidanceinthissectioncoversCHPsystemswithatotalpowercapacitylessthan5MWeusedincommercialapplications.TheCHPunitsmayormaynotsupplycommunityheating.

Guidanceoncommunityheatingsystemswithmicro-CHP(havingatotalpowercapacitylessthan5kWe)andotherheatgeneratorsisavailableintheDomestic Building Services Compliance Guide.

6.3 KeytermsCombinedheatandpower(CHP) means thesimultaneousgenerationofheatandpowerinasingleprocess.Thepoweroutputisusuallyelectricity,butmayincludemechanicalpower.Heatoutputscanincludesteam,hotwaterorhotairforprocessheating,spaceheatingorabsorptioncooling.

CombinedHeatandPowerQualityAssurance(CHPQA) isascheme28underwhichregistrationandcertificationofCHPsystemsiscarriedoutaccordingtodefinedqualitycriteria.

CHPQAqualityindex isanindicatoroftheenergyefficiencyandenvironmentalperformanceofaCHPschemerelativetogenerationofthesameamountsofheatandpowerbyalternativemeans.

Powerefficiency isthetotalannualpoweroutputdividedbythetotalannualfuelinputofaCHPunit.

28 FurtherinformationabouttheCHPQAprogrammeisavailableatwww.chpqa.com.



38


6.4CHPinnewandexistingbuildingsCHPplantinnewandexistingbuildingsshouldhave:

a. aminimumCHPQAqualityindex(QI)of105andpowerefficiencygreaterthan20%,bothunderannualoperation

b. acontrolsystemthat,asaminimum,ensuresthattheCHPunitoperatesastheleadheatgenerator

c. meteringtomeasurehoursrun,electricitygeneratedandfuelsuppliedtotheCHPunit.

TheCHPplantshouldbesizedtosupplynotlessthan45%oftheannualtotalheatingdemand(i.e.spaceheating,domestichotwaterheatingandprocessheating)unlessthereareoverridingpracticaloreconomicconstraints.

Calculating the carbon dioxide emissions from a CHP heating system

CHPmaybeusedasamainorsupplementaryheatsourceincommunityheatingsystems.TocalculatethecarbondioxideemissionrateforanewbuildingforthepurposesofshowingcompliancewiththeBuildingRegulations,thefollowingdatawillneedtobeenteredintoanaccreditedNCMtoolsuchasSBEM:

a. theproportion(P%)oftheannualheatdemand(HMWh)tobesuppliedbytheCHPplant(HP).ThisisneededastheCHPunitisnormallysizedbelowthepeakheatdemandofthebuildingandwillalsobeoutofserviceformaintenancepurposes

b. theoverallefficiencyratiooftheCHPplant(E)asdefinedbyEquation5andtakingaccountofpart-loadoperationandallheatrejectionpredictedbyanoperatingmodel:

E(annualusefulheatsuppliedannualelectricitygeneratednetofparasiticelectricityuse)/annualenergyofthefuelsupplied(ingrosscalorificvalueterms) Equation 5

c. theheattopowerratiooftheCHPplant(R),calculatedfortheannualoperationaccordingtoEquation6:

Rannualusefulheatsupplied/annualelectricitygeneratednetofparasiticelectricityuse Equation 6

Thecarbondioxideemittedinkg/yearfortheheatsuppliedbyagas-firedCHPplantisthen:

H P

H P 216

H P 519

E R E R

where216and519aretheassumedcarbondioxideemissionfactorsing/kWhformainsgasandgrid-displacedelectricityrespectively. Equation 7

ThecarbondioxideemittedforthebalanceofheatsuppliedbytheboilersisthencalculatedbytheNCMtoolasforaboileronlysystem.



39

Section 6: Combined heat and power and community heating


Communityheatingsystemsmayincludeotherlowandzerocarbonsourcesofenergysuchasbiomassheating.Emissionfactorsshouldbedeterminedbasedontheparticulardetailsofthescheme,butshouldtakeaccountoftheannualaverageperformanceofthewholesystem–thatis,ofthedistributioncircuitsandalltheheatgeneratingplant,includinganyCHPandanywasteheatrecoveryorheatdumping.Thecalculationofthebuildingcarbondioxideemissionrateshouldbecarriedoutbyasuitablyqualifiedperson,whoshouldexplainhowtheemissionfactorswerederived.

Thedesignofthecommunityheatingconnectionandthebuilding’sheatingcontrolsystemshouldtakeaccountoftherequirementsofthecommunityheatingorganisationwithrespecttomaintaininglowreturntemperaturesatpart-loadandlimitingthemaximumflowratetobesuppliedbythecommunityheatingsystemtotheagreedlevel.Aheatmetershouldbeinstalledtomeasuretheheatenergysuppliedandtomonitorthemaximumheatdemand,themaximumcommunityheatingflowrateandthereturntemperaturesintothecommunityheatingnetwork.

Furtherguidancecanbefoundinthefollowingdocuments:

• CarbonTrustGPG234Community heating and CHP

• CIBSEAM12 Small-scale CHP for buildings

• HVCATR/30 Guide to good practice – Heat pumps.



40


Section7:Directelectricspaceheating

7.1 IntroductionThissectiongivesguidanceonspecifyingdirectelectricheatersforspaceheatinginnewandexistingbuildings.Itaddressestherelevantelectricheatertypesandtheminimumprovisionofcontrols.

7.2 ScopeofguidanceTheguidancegiveninthissectioncoversthefollowingtypesofelectricheatingsystems,whichmaybeusedtoprovideprimaryorsecondaryspaceheating:

• electricboilers

• electricwarmairsystems

• electricpanelheaters

• electricstoragesystems,includingintegratedstorage/directsystems

• electricfanheatersandfanconvectorheaters

• electricradiantheaters,includingquartzandceramictypes.

Theguidancedoesnotcoverelectricheatpumpsorportableelectricheatingdevices.

7.3 ElectricspaceheatinginnewandexistingbuildingsItisassumedthatelectricheatingdevicesconvertelectricitytoheatwithinabuildingwithanefficiencyof100%.Aminimumheatgeneratorseasonalefficiencyisthereforenotspecified.

Electricspaceheatingsystemsinnewandexistingbuildingsshouldmeettheminimumstandardsfor:

a. controlsforelectricboilersinTable23

b. controlsforelectricheatingsystemsotherthanboilersinTable24.



41

Section 7: Direct electric space heating

Table 23 Recommended minimum controls for electric boiler systems

Type of control Standard Comments

Boilertemperaturecontrol

a. Boilerfittedwithaflowtemperaturecontrolandcapableofmodulatingthepowerinputtotheprimarywaterdependingonspaceheatingconditions.

Zoning b. Forbuildingswithatotalusablefloorareagreaterthan150m2,atleasttwospaceheatingzoneswithindependenttimeandtemperaturecontrolsusingeither:i. multipleheatingzoneprogrammers,orii. asinglemulti-channelprogrammer.

Temperaturecontrolofspaceheating

c. Separatetemperaturecontrolofzoneswithinthebuildingusingeither:i. roomthermostatsorprogrammableroomthermostatsinall

zones,orii. aroomthermostatorprogrammableroomthermostatinthe

mainzoneandindividualradiatorcontrolssuchasthermostaticradiatorvalves(TRVs)onallradiatorsintheotherzones,or

iii. acombinationof(i)and(ii)above.

Timecontrolofspaceandwaterheating

d. Provideusing:i. afullprogrammerwithseparatetimecontrolforeachcircuit,

orii. separatetimersforeachcircuit,oriii. programmableroomthermostatsfortheheatingcircuits,with

separatetimecontrolforallthecircuits.

Note:Anacceptablealternativetotheabovecontrolsisanyboilermanagementcontrolsystemthatmeetsthespecifiedzoning,timingandtemperaturerequirements.



42


Table 24 Recommended minimum controls for primary and secondary electric heating systems other than electric boilers

Type of electric heating system Type of control Standard Comments

Warmair Timeandtemperaturecontrol,eitherintegraltotheheaterorexternal

a. Atimeswitch/programmerandroomthermostat,or

b. aprogrammableroomthermostat.

Zonecontrol c. Forbuildingswithatotalusablefloorareagreaterthan150m2,atleasttwospaceheatingcircuitswithindependenttimingandtemperaturecontrolsusingeither:i. multipleheatingzoneprogrammers,orii. asinglemulti-channelprogrammer.

Radiantheaters Zoneoroccupancycontrol

a. Connectiontoapassiveinfra-reddetector. Electricradiantheaterscanprovidezoneheatingorbeusedforafullheatingscheme.Commonelectricradiantheatersincludethequartzandceramictypes.

Panel/skirtingheaters

Localtimeandtemperaturecontrol

a. Timecontrolprovidedby:i. aprogrammabletimeswitchintegratedinto

theappliance,orii. aseparatetimeswitch.

b. Individualtemperaturecontrolprovidedby:i. integralthermostats,orii. separateroomthermostats.

Panelheatersystemsprovideinstantaneousheat.

Storageheaters Chargecontrol a. Automaticcontrolofinputcharge(basedonanabilitytodetecttheinternaltemperatureandadjustthechargingoftheheateraccordingly).

Temperaturecontrol b. Manualcontrolsforadjustingtherateofheatreleasefromtheappliance,suchasadjustabledamperorsomeotherthermostatically-controlledmeans.

Fan/fanconvectorheaters

Localfancontrol a. Aswitchintegratedintotheappliance,orb. aseparateremoteswitch.

Individualtemperaturecontrol

c. Integralswitches,ord. separateremoteswitching.



43

Section 8: Domestic hot water

Section8:Domestichotwater

8.1 IntroductionThissectiongivesguidanceonspecifyingdomestichotwater(DHW)systemsfornewandexistingbuildingstomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.Itincludesguidanceonmeasures,suchasadditionalcontrols,thatcanbeusedtogainheatingefficiencycreditstoimprovetheheatgeneratorseasonalefficiency.

Note:Waterqualitycanhaveamajorimpactonsystemefficiency.Itisimportantthatdesignerstakeappropriatemeasurestoensurethatthesystemwaterisofgoodquality.

AswellastheBuildingRegulations,otherregulationsapplytotheprovisionofdomestichotwater.Energy-savingmeasuresshouldnotcompromisethesafetyofpeopleortheabilityofthesystemtoachieveapprovedregimesforthecontroloflegionella.

DomestichotwatersystemsarereferredtoashotwaterservicesystemsinSBEM.

8.2ScopeofguidanceTheguidanceinthissectioncoverstheconventionaldirectandindirectgas-fired,oil-firedandelectrically-heateddomestichotwatersystemsshowninTable25.

Therecommendedminimumstandardssetoutinthissectionapplyonlytodedicatedwaterheaters.CentralheatingboilerswhichprovidespaceheatinganddomestichotwatershouldmeettheminimumstandardsinSection2;andheatpumpswhichprovidedomestichotwatershouldmeettheminimumstandardsinSection3.

Theguidanceinthissectionappliestoback-upgasandelectricsystemsusedwithsolarthermalhotwatersystems,butnottosolarthermalsystemsthemselves.Forsolarsystemswithacylindercapacityoflessthan440litresorcollectorsurfacearealessthan20m2,consulttheDCLGDomestic Building Services Compliance Guide,orforlargersystems,theCIBSESolar heating design and installation guide.



44


Table 25 Types of hot water system

Direct-firedcirculator:naturalgasandLPG

Asysteminwhichthewaterissuppliedtothedraw-offpointsfromahotwatervesselinwhichwaterisheatedbycombustiongasesfromaprimaryenergysource.Theunithasnostoragevolumeaswaterisstoredinasupplementarystoragevessel.

Direct-firedstorage:naturalgas,LPGandoil

Asysteminwhichthewaterissuppliedtothedraw-offpointsfromanintegralhotwatervesselinwhichwaterisheatedbycombustiongasesfromaprimaryenergysource.

Direct-firedcontinuousflow:naturalgasandLPG

Asysteminwhichthewaterissuppliedtothedraw-offpointsfromadeviceinwhichcoldwaterisheatedbycombustiongasesfromaprimaryenergysourceasitflowsthroughthewaterheater.Thewaterheaterissituatedclosetothedraw-offpoints.Theunithasnostoragevolumeaswaterisinstantaneouslyheatedasitflowsthroughthedevice.

Indirect-firedcirculator:naturalgas,LPGandoil

Asysteminwhichthewaterissuppliedtothedraw-offpointsfromadeviceinwhichwaterisheatedbymeansofanelementthroughwhichtheheatingmediumiscirculatedinsuchamannerthatitdoesnotmixwiththehotwatersupply.Inpracticetheheatsourceislikelytobeaboilerdedicatedtothesupplyofdomestichotwater.

Instantaneouselectrically-heated

Asysteminwhichthewaterissuppliedtothedraw-offpointsfromadeviceinwhichcoldwaterisheatedbyanelectricelementorelementsasitflowsthroughthewaterheater.Thewaterheaterissituatedclosetothedraw-offpoints.Theunithasnostoragevolumeaswaterisinstantaneouslyheatedasitflowsthroughthedevice.

Point-of-useelectrically-heated

Asysteminwhichthewaterissuppliedtothedraw-offpointsfromadeviceinwhichwaterisheatedbyanelectricelementorelementsimmersedinthestoredwater.Thewaterheaterissituatedclosetothedraw-offpointsandshouldhaveastoragecapacitynogreaterthan100litres.

Localelectrically-heated

Asysteminwhichthewaterissuppliedtothedraw-offpointsfromadeviceinwhichwaterisheatedbyanelectricelementorelementsimmersedinthestoredwater.Thewaterheaterissituatedinthelocalityofthedraw-offpointsandshouldhaveastoragecapacityofbetween100and300litres.Bulkheatingofthewaterheatershouldbewithoff-peakelectricity.

Centralisedelectrically-heated

Asysteminwhichthewaterissuppliedtothedraw-offpointsfromadeviceinwhichwaterisheatedbyanelectricelementorelementsimmersedinthestoredwater.Thewaterheaterissituatedcentrallywithadistributionsystemtosupplywatertothedrawoff-pointsandshouldhaveacapacitygreaterthan300litres.Bulkheatingofthewaterheatershouldbewithoff-peakelectricity.

8.3 KeytermsTheheatgeneratorseasonalefficiencyisdefinedforeachsystemtypeinTable26.

TheeffectiveheatgeneratorseasonalefficiencyistheheatgeneratorseasonalefficiencyplusheatingefficiencycreditsgainedbyadoptingadditionalmeasuresfromTable31.



45


Table 26 Definition of heat generator seasonal efficiency for DHW systems

DHW system type Heat generator seasonal efficiency Comments on calculation[1]


Equalsthethermalefficiencyoftheheater(grosscalorificvalue)whentestedtoBSEN15502-2-1:201229.[2]

Exclude:a. secondarypipeworkb. fansandpumpsc. divertervalves,solenoids,

actuatorsd. supplementarystorage

vessels.


Equalsthethermalefficiencyoftheheater(grosscalorificvalue)whentestedusingtheproceduresinBSEN89:200030.[2]

Include thewaterheaterandinsulationoftheintegralstoragevesselonly.


Equalsthethermalefficiencyoftheheater(grosscalorificvalue)whentestedtoBSEN26:199831.

Exclude:a. secondarypipeworkb. fansandpumpsc. divertervalves,solenoids,

actuatorsd. supplementarystorage

vessels.

Indirect-firedcirculator:naturalgas,LPGandoil

CalculateusingEquations2,3.1,or3.2and3.3(asappropriate)inSection2.

UseEquation2(0.8130%

0.19100%

)tocalculateboilerseasonalefficiencyifprimaryreturntemperature55°C.

Useboilerfullloadefficiency(1.0100%

)at80/60°Cflow/returntemperaturesifprimaryreturntemperature55°C.

IfboilerseasonalefficiencyvaluesareobtainedasnetvaluesthefactorsinSAP2012TableE4shouldbeusedtoconverttogrossvalues.

Include theheatgeneratoronly.

Electrically-heated Theseareassumed100%thermallyefficientintermsofconversiontoheatwithinthebuilding.

Notes[1] Forhotwatersystemsinnewbuildings,standinglossesarecalculatedintheaccreditedNCMtool.[2] Whereefficiencydataisnotreadilyavailable,efficienciescanbecalculatedusingmanufacturers’recoveryratesand

thefollowingequations:

Grossthermalefficiencyheateroutput/grossinput Equation 8

Heateroutputrecoveryrateofheaterinlitres/secondspecificheatcapacityofwatertemperatureriseofwater Equation 9

29 BSEN15502-2-1:2012Specific standard for type C appliances and type B2, B3 and B5 appliances of a nominal heat input not exceeding 1000 kW.30 BSEN89:2000Gas fired water heaters for the production of domestic hot water. Direct-fired storage water heaters, Section 8.2, Maintenance consumption.31 BSEN26:1998Gas fired instantaneous water heaters for the production of domestic hot water, fitted with atmospheric burners.



46


8.4DomestichotwatersystemsinnewandexistingbuildingsDomestichotwatersystemsinnewandexistingbuildingsshouldmeettherecommendedminimumstandardsfor:

a. heatlossesfromDHWstoragevesselsinTable27,ormaintenanceconsumptionvaluesinBSEN89:2000

b. heatgeneratorefficiency(grosscalorificvalue)inTable28

c. controlsinTables29and30.

Table 27 Recommended maximum heat losses from DHW storage vessels

Nominal volume(litres)

Heat loss(kWh/24h)

Nominal volume (litres)

Heat loss(kWh/24h)

200 2.1 900 4.5

300 2.6 1000 4.7

400 3.1 1100 4.8

500 3.5 1200 4.9

600 3.8 1300 5.0

700 4.1 1500 5.1

800 4.3 2000 5.2

Notes[1] ForguidanceonmaximumheatlossesfromDHWstoragevesselswithastoragevolumelessthan200litres,see

BSEN15450:200732.[2] Theheatlossfromelectrically-heatedcylinders(volumeVlitres)shouldnotexceed1.28(0.20.051V2/3)

ifpoint-of-useor1.28(0.051V2/3)iflocal.

32 BSEN15450:2007Heating systems in buildings. Design of heat pump heating systems.



47


Table 28 Recommended minimum thermal efficiencies for domestic hot water systems

DHW system type Fuel type Heat generator seasonal efficiency (gross)

Thermal efficiencyBoiler seasonal efficiency

Direct-fired:newbuildings



LPG30kWoutput 92%

LPG30kWoutput 74%

Oil 76%

Direct-fired:existingbuildings

Naturalgas 73%

LPG 74%

Oil 75%

Indirect-fired:newandexistingbuildings

Naturalgas 80%

LPG 81%

Oil 82%

Electrically-heated:newandexistingbuildings

100%assumed

Table 29 Recommended minimum controls package for gas and oil-fired domestic hotwater systems

DHW system type Controls package


a. Automaticthermostatcontroltoshutofftheburner/primaryheatsupplywhenthedesiredtemperatureofthehotwaterhasbeenreached.

b. Highlimitthermostattoshutoffprimaryflowifsystemtemperaturetoohigh.c. Timecontrol.





a. Outlettemperatureofappliancecontrolledbyrateofflowthroughheatexchanger.b. Highlimitthermostattoshutoffprimaryflowifsystemtemperaturetoohigh.c. Flowsensorthatonlyallowselectricalinputshouldsufficientflowthroughtheunitbe

achieved.d. Timecontrol.

Indirect-fired:naturalgas,LPGandoil





48


Table 30 Recommended minimum controls package for electrically-heated domestic hotwater systems

Point-of-use Local Centralised Instantaneous

Automaticthermostatcontroltointerrupttheelectricalsupplywhenthedesiredstoragetemperaturehasbeenreached.

Yes Yes Yes x

Highlimitthermostat(thermalcut-out)tointerrupttheenergysupplyifthesystemtemperaturegetstoohigh.

Yes Yes Yes x

Manualresetintheeventofanover-temperaturetrip. Yes Yes Yes x

7-daytimeclock(orBMSinterface)toensurebulkheatingofwaterusingoff-peakelectricity.Facilitytoboostthetemperatureusingon-peakelectricity(ideallybymeansofanimmersionheaterfittedtoheatthetop30%ofthecylinder).

x Yes Yes x

Highlimitthermostat(thermalcut-out)tointerrupttheenergysupplyiftheoutlettemperaturegetstoohigh.(Note:Outlettemperatureiscontrolledbyrateofflowthroughtheunit,whichonbasicunitswouldbebytheoutlettaporfitting.)

x x x Yes

Flow/pressuresensorthatonlyallowselectricalinputshouldsufficientflowthroughtheunitbeachieved.

x x x Yes

8.5Supplementaryinformationonelectricwaterheaters

Point-of-use

• RelevantstandardisBSEN60335-2-21:2003+A2:200833.

Instantaneous

• RelevantstandardisBSEN60335-2-35:2002+A2:201134.

Local

• Forventedsystems,relevantstandardisBSEN60335-2-21:2003+A2:2008.

• Forunventedsystems,relevantstandardisBSEN12897:200635.

Centralised

• RelevantstandardisBS853-1:1990+A3:201136.

• Bulkheatingofthewatershouldutiliseoff-peakelectricitywherepossible.

• Whenusingoff-peakelectricitya‘boostheater’shouldbefittedtoallow‘on-peak’heating.Theboostheatershouldheatthetop30%ofthecylinderandberatedtoapproximately30%ofthemainoff-peakheaterbattery.ThekWloadwilldependontherecoverytimerequired.

33 BSEN60335-2-21:2003+A2:2008Specification for safety of household and similar electrical appliances. Particular requirements for storage water heaters.34 BSEN60335-2-35:2002+A2:2011Specification for safety of household and similar electrical appliances. Particular requirements for instantaneous water heaters.35 BSEN12897:2006 Water supply. Specification for indirectly heated unvented (closed) storage water heaters.36 BS853-1:1990+A3:2011Calorifiers and storage vessels for central heating and hot water supplies.



49


• Theheaterbatteryshouldeitherbeofremovablecoreorrodelementconstruction.Removablecoreconstructionallowselementstobechangedwithoutremovingtheheaterfromthevesselordrainingthesystem.Forremovablecoreconstruction,themaximumelementwattsdensityshouldnotexceed3W/cm2forcoppertubesor2.5W/cm2forstainlesssteeltubes.Forrodelementconstruction,elementsshouldbeofnickelalloy825sheath,beU-bentandhaveamaximumwattsdensityof10W/cm2.Temperaturecontrolshouldbebymeansof‘on/off’controloftheheaterbatteryutilisingstagerampingforloadingsabove30kW.Thermostaticcontrolisanidealsolution.

• Thecontrolsensorshouldbemountedinthecylinderatanangleofapproximately45°totheheaterandataleveljustabovetheheatingbundle.Theover-temperaturesensor(highlimit)shouldbemountedinthetop30%ofthecylinderdirectlyabovetheheaterbundle.Amanualresetshouldberequiredintheeventofanover-temperaturetrip.

• Forloadingsgreaterthan6kW,temperaturesensorsshouldnotbefittedtotheheaterbundle.Thisistopreventthermostatandcontactorcyclingwhichwillleadtoprematurefailureoftheequipmentandpoortemperaturecontrol.

8.6HeatingefficiencycreditsfordomestichotwatersystemsinnewandexistingbuildingsHeatingefficiencycreditsareavailableforgasandoil-firedsystemsfortheadditionalmeasureslistedinTable31.Ifthesemeasuresareadopted,heatingefficiencycreditscanbeaddedtotheheatgeneratorseasonalefficiencytogivetheeffectiveheatgeneratorseasonalefficiency,whichisthevalueenteredintotheaccreditedNCMtoolinordertocalculatethecarbondioxideemissionrateforabuilding.

Effectiveheatgeneratorseasonalefficiencyheatgeneratorseasonalefficiencyheatingefficiencycredits

wheretheheatgeneratorseasonalefficiencyis:

• thethermalefficiencyfordirect-firedsystems

• theboilerseasonalefficiencyforindirect-firedsystems.

Table 31 Heating efficiency credits for additional measures applicable to domestic hot water systems

System type Measure Heating efficiency credits (%points)

All Decentralisation 2,butnotapplicabletosystemsinnewbuildings

Direct-fired Integralcombustioncircuitshut-offdevice 1

Fullyautomaticignitioncontrols 0.5

All Correctsizeofunitconfirmedusingmanufacturer’stechnicalhelplineandsizingsoftware

2



50


Example: Usingheatingefficiencycredits toimprovetheheatgeneratorseasonalefficiencyforadirect-firedcirculatorsystem

Step 1: Calculatingthermalefficiency ofdirect-firedDHWsystem

• recoveryrateofheater0.3830litres/s

• grossinputrateofheater83.5kW

• specificheatcapacityofwater4.186kJ/(kg.K)

• temperatureriseofwaterinsideheater50°C.

UsingEquation9:

Heateroutputrecoveryrateofheaterinlitres/secondspecificheatcapacityofwatertemperatureriseofthewater

0.38304.1865080.16kW

UsingEquation8:

Thermalefficiency(gross)outputoftheheater/grossinput

• 80.16/83.50.96(96%)

Step 2: Addingheatingefficiencycredits foradditionalmeasures

Theheaterhasbeensizedtocloselymatchthesystemdemandbyusingthemanufacturer’ssizingguideandhasfullyautomaticcontrols.

Table32showshowcreditswouldbeassignedinthisexample.

Table 32 Example to illustrate allocation of heating efficiency credits for a DHW system


Sizedaccordingtomanufacturer’sguidance 2

Fullyautomaticignitioncontrols 0.5

Total credits 2.5

Effectiveheatgeneratorseasonalefficiencythermalefficiency(gross)heatingefficiencycredits

962.598.5%

Inthisexample,thevalue98.5%wouldbeenteredintheNCMtool.



51

Section 9: Comfort cooling

Section9:Comfortcooling

9.1 IntroductionThissectiongivesguidanceonspecifyingcomfortcoolingfornewandexistingbuildingstomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.ItincludesguidanceonusingSBEMtocalculatethecarbondioxideemissionsassociatedwithcomfortcoolinginnewbuildings.

9.2ScopeofguidanceTheguidancecoversthespecificationofrefrigerationplantefficiencyintermsoftheseasonalenergyefficiencyratio(SEER),whichisthevalueusedbySBEMtocalculatethecarbondioxideemissionrateforanewbuilding.SBEMallocatesstandardcorrectionfactors37totheperformanceofcoolingplanttoaccountfortheuseofthedifferentsystemsfordistributingcoolingtothespaces.Evaporativecoolinganddesiccantcoolingsystemsarenotwithinthescopeofthisguidance.

9.3 KeytermsCoolingplant meansthatpartofacoolingsystemthatproducesthesupplyofcoolingmedium.Itdoesnotincludemeansofdistributingthecoolingmediumorthedeliveryofthecoolingintotherelevantzone.Itmayconsist,forexample,ofasinglechilleroraseriesofchillers.

Coolingsystem means thecompletesystemthatisinstalledtoprovidethecomfortcoolingtothespace.Itincludesthecoolingplantandthesystembywhichthecoolingmediumeffectscoolingintherelevantzoneandtheassociatedcontrols.Thiswillinsomecasesbeacompletepackagedairconditioner.

Energyefficiencyratio(EER) forchillersisthecoolingenergydeliveredintothecoolingsystemdividedbytheenergyinputtothechiller,asdeterminedbyBSEN1451138.

Inthecaseofpackagedairconditioners,theEERistheenergyremovedfromairwithintheconditionedspacedividedbytheeffectiveenergyinputtotheunit,asdeterminedbyBSEN14511orotherappropriatestandardprocedure.ThetestconditionsfordeterminingEERarethosespecifiedinBSEN14511.

Partloadenergyefficiencyratio isthecoolingenergydeliveredintothecoolingsystemdividedbytheenergyinputtothecoolingplant.Partloadperformanceforindividualchillersisdeterminedassumingchilledwaterprovisionat7°Coutand12°Cin(at100%load),underthefollowingconditions:

Percentage part load 25% 50% 75% 100%

Air-cooledchillersambientairtemperature(°C)

20 25 30 35

Water-cooledchillersenteringcoolingwatertemperature(°C)

18 22 26 30

Seasonalenergyefficiencyratio(SEER)isthetotalamountofcoolingenergyprovideddividedbythetotalenergyinputtoasinglecoolingunit,summedovertheyear.

37 TheSBEMTechnicalManualisavailablefordownloadfromwww.ncm.bre.co.uk38 BSEN14511-2:2013Air conditioners, liquid chilling packages and heat pumps with electrically driven compressors for space heating and cooling. Test conditions.



52


EuropeanSeasonalEnergyEfficiencyRatio(ESEER)istheSEERofacoolingunitasdeterminedundertheEuroventCertificationscheme.

Plantseasonalenergyefficiencyratio(PSEER)isthetotalamountofcoolingenergyprovideddividedbythetotalenergyinputtothecoolingplant(whichmaycomprisemorethanonecoolingunit),summedovertheyear.

9.4ComfortcoolinginnewandexistingbuildingsForcomfortcoolingsystemsinnewandexistingbuildings:

a. coolingunitsshouldcomplywithEuropeanCommissionRegulationNo327/2011forfansdrivenbymotorswithanelectricalinputpowerbetween125Wand500kW,andRegulationNo206/2012forsystemswithacoolingcapacityofupto12kW,bothimplementingDirective2009/125/ECwithregardstoecodesignrequirementsforenergy-relatedproducts

b. thefullloadenergyefficiencyratio(EER)ofeachcoolingunitofthecoolingplantshouldbenoworsethanrecommendedinTable33

c. controlsshouldcomplywithBSEN15232:201239BandCandbenoworsethanrecommendedinTable34.

Table 33 Recommended minimum energy efficiency ratio (EER) for comfort cooling

Type Cooling unit full load EER

Packagedairconditioners Single-ducttype 2.6

Othertypes 2.6

Splitandmulti-splitairconditioners12kW 2.6

Splitandmulti-splitairconditioners12kW SCOP‘D’ratingformediantemperaturerangeinBSEN14825:201340

Variablerefrigerantflowsystems 2.6

Vapourcompressioncyclechillers,water-cooled750kW 3.9

Vapourcompressioncyclechillers,water-cooled750kW 4.7

Vapourcompressioncyclechillers,air-cooled750kW 2.55

Vapourcompressioncyclechillers,air-cooled750kW 2.65

Waterloopheatpump 3.2

Absorptioncyclechillers 0.7

Gas-engine-drivenvariablerefrigerantflow 1.0

39 BSEN15232:2012Energy performance of buildings. Impact of building automation, controls and building management.40 BSEN14825:2013Air conditioners, liquid chilling packages and heat pumps with electrically driven compressors for space heating and cooling. Testing and rating at part load conditions

and calculation of seasonal performance.



53


Table 34 Recommended minimum controls for comfort cooling in new and existing buildings

Controls

Cooling plant a. Multiplecoolingunitsshouldbeprovidedwithcontrolsthatensurethecombinedplantoperatesinitsmostefficientmodes.

Cooling system a. Terminalunitscapableofprovidingcoolingshouldhaveintegratedorremotetimeandtemperaturecontrols.

b. Inanygivenzonesimultaneousheatingandcoolingshouldbepreventedbyaninterlock.

9.5 CalculatingtheseasonalenergyefficiencyratioforSBEMThevalueoftheSEERtobeusedintheSBEMtoolcanbecalculatedinanumberofwaysaccordingtotheavailabilityofinformationandtheapplication.

Ingeneral,whereanindustryapprovedtestprocedureforobtainingperformancemeasurementsofcoolingunitsatpartialloadconditionsexists,andthecoolingloadprofileoftheproposedbuildingisknown,theSEER ofthecoolingunitisgivenby:

SEERa(EER100%)b(EER

75%)c(EER

50%)d(EER

25%) Equation 10

where:

EERxistheEERmeasuredattheloadconditionsof100%,75%,50%and25%attheoperating

conditionsdetailedunderthepartloadenergyefficiencyratioinSection9.3

and:

a,b,canddaretheloadprofileweightingfactorsrelevanttotheproposedapplication.

ThefollowingsectionsdescribehowtheSEERmaybecalculatedforthespecificcasesof:

• coolingunitswithnopartloadperformancedata

• unknownloadprofiles

• office-typeaccommodation

• otherbuildingswithknownloadprofiledata

• multiple-chillersystems

• systemswithfreecoolingorheatrecovery

• absorptionchillersanddistrictcooling.

Cooling units with no part load performance data

Forcoolingunitsthathavenopartloaddata,theSEERisthefullloadEER.

Unknown load profiles

ForapplicationswheretheloadprofileunderwhichthecoolingplantoperatesisnotknownbutthereissomedataonchillerpartloadEER,then:

a. forchillerswherethefullandhalfload(50%)EERsareknown,theSEERistheaverageoftheEERs,i.e.the100%and50%areequallyweighted

b. forchillerswithfourpointsofpartloadEER,theSEERiscalculatedusingEquation10witheachEERweightedequally,i.e.a,b,canddeachequalto0.25



54


c. ifthechilleruseddoesnothavedataforfourstepsofload,thentheweightsareapportionedappropriately.

Office-type accommodation

Forapplicationsingeneraloffice-typeaccommodation,thefollowingweightingfactorscanbetakenasrepresentativeoftheloadprofile:

a b c d

0.03 0.33 0.41 0.23

TheseweightingfactorsarethesameasthoseusedforthedeterminationoftheEuropeanSeasonalEnergyEfficiencyRatio(ESEER).MostmanufacturerspublishESEERfiguresandthesecanbeverifiedbyreferencetotheEuroventCertificationwebsiteatwww.eurovent-certification.com.TheESEERvalueisthenusedastheSEERintheSBEMcalculation.

Examples

1. ForasinglechillerwithEERof2.9(knownatfullloadonly):

SEER2.9

2. Forachillerwith100%and50%EERsof2.0and2.5respectivelyinabuildingwithunknownloadprofile:

SEER2.25

3. ForachillerwithunknownapplicationloadprofileandpartloadEERsofEER100%

2.89,EER75%

3.93,EER

50%4.89andEER

25%4.79:

SEER0.252.890.253.930.254.890.254.794.125

4. IfthesamechillerisusedinanofficethentheESEERweightingfactorsareused:

SEERESEER0.032.890.333.930.414.890.234.794.49

Other buildings with known load profile

Iftheloadprofileisknownfromdetailedsimulationorprediction,theSEERmaybederivedfromEquation10aboveusingappropriateweightsandEERsatgivenloads.

Multiple-chiller systems

Forplantswithmultiple-chillers,aplantseasonalenergyefficiencyratio(PSEER)valuemaybecalculatedbasedonthesumoftheenergyconsumptionsofalltheoperatingchillers.Inthiscasecaremustbetakentoincludeallthefactorsthatcaninfluencethecombinedperformanceofthemultiple-chillerinstallation.Thesewillincludethe:

• degreeofoversizingofthetotalinstalledcapacity

• sizesofindividualchillers

• EERsofindividualchillersatactualoperatingconditions

• controlmodeused:e.g.parallel,sequential,dedicatedlowloadunit

• loadprofileoftheproposedbuilding

• buildinglocation(asthisdeterminesambientconditions).



55


WhentheseareknownitmaybepossibletocalculateaPSEERwhichmatchestheproposedinstallationmorecloselythanbyapplyingthesimplificationsdescribedearlier.ThisPSEERvalueisthenusedastheSEERintheSBEMcalculation.

Systems with free cooling or heat recovery

SystemsthathavetheabilitytousefreecoolingorheatrecoverycanachieveagreaterSEERthanmoreconventionalsystems.InthesecasestheSEERmustbederivedforthespecificapplicationunderconsideration.

Absorption chillers and district cooling

Absorptionchillersmaybeusedinconjunctionwithon-siteCHPoracommunityordistrictheatingsystem.ThecarbondioxideemissionsarecalculatedinthesamewayaswhenusingCHPforheating.Thecontrolsystemshouldensureasfaraspossiblethatheatfromboilersisnotusedtosupplytheabsorptionchiller.TheminimumfullloadEERoftheabsorptionchillersshouldbenoworsethan0.7.

Whereadistrictcoolingschemeexists,lowercarbondioxideemissionsmayresultifthecoolingisproducedcentrallyfromCHP/absorptionchillers,heatpumpsorhighefficiencyvapourcompressionchillers.Thedistrictcoolingcompanywillprovideinformationonthecarbondioxidecontentofthecoolingenergysupplied,andthisfigurecanthenbeusedtocalculatethecarbondioxideemissionrateforthebuilding.

9.6Supplementaryinformation

BSEN15243:200741providesadditionalguidanceoncalculatingtheseasonalefficiencyofcoldgeneratorsandchillersinairconditioningsystems.TheguidancedoesnotneedtobefollowedtomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.

41 BSEN15243:2007Ventilation for buildings. Calculation of room temperatures and of load and energy for buildings with room conditioning systems.



56


Section10:Airdistribution

10.1 IntroductionThissectiongivesguidanceonspecifyingairdistributionsystemsfornewandexistingbuildingstomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.

10.2 ScopeofguidanceTheguidanceappliestothefollowingtypesofairdistributionsystem:

• centralairconditioningsystems

• centralmechanicalventilationsystemswithheating,coolingorheatrecovery

• allcentralsystemsnotcoveredbytheabovetwotypes

• zonalsupplysystemswherethefanisremotefromthezone,suchasceilingvoidorroof-mountedunits

• zonalextractsystemswherethefanisremotefromthezone

• localsupplyandextractventilationunitssuchaswindow,wallorroofunitsservingasinglearea(e.g.toiletextract)

• otherlocalventilationunits,e.g.fancoilunitsandfanassistedterminalvariableairvolume(VAV)units

• kitchenextract,fanremotefromzonewithgreasefilter.

Gasandoil-firedairheatersinstalledwithintheareatobeheatedarenotwithinthescopeofthissection.

10.3 KeytermsAirconditioningsystem means acombinationofcomponentsrequiredtoprovideaformofairtreatmentinwhichtemperatureiscontrolledorcanbelowered,possiblyincombinationwiththecontrolofventilation,humidityandaircleanliness.

Ventilationsystem means acombinationofcomponentsrequiredtoprovideairtreatmentinwhichtemperature,ventilationandaircleanlinessarecontrolled.

Centralsystemmeans asupplyandextractsystemwhichservesthewholeormajorzonesofthebuilding.

Localunit means anunductedventilationunitservingasinglearea.

Zonalsystem means asystemwhichservesagroupofroomsformingpartofabuilding,i.e.azonewhereductingisrequired.



57

Section 10: Air distribution

Demandcontrol isatypeofcontrolwheretheventilationrateiscontrolledbyairquality,moisture,occupancyorsomeotherindicatoroftheneedforventilation.

Specificfanpower(SFP) ofanairdistributionsystem means thesumofthedesigncircuit-wattsofthesystemfansthatsupplyairandexhaustitbackoutdoors,includinglossesthroughswitchgearandcontrolssuchasinverters(i.e.thetotalcircuit-wattsforthesupplyandextractfans),dividedbythedesignairflowratethroughthatsystem.

Forthepurposesofthisguide,thespecificfanpowerofanairdistributionsystemshouldbecalculatedaccordingtotheproceduresetoutinBSEN13779:200742AnnexDCalculation and application of specific fan power. Calculating and checking the SFP, SFP

E and SFP

V.

SFP P

sfP

ef Equation 11q

where:

SFPisthespecificfanpowerdemandoftheairdistributionsystem(W/(l.s))

Psf isthetotalfanpowerofallsupplyairfansatthedesignairflowrate,includingpowerlosses

throughswitchgearandcontrolsassociatedwithpoweringandcontrollingthefans(W)

Pefisthetotalfanpowerofallexhaustairfansatthedesignairflowrateincludingpowerlosses

throughswitchgearandcontrolsassociatedwithpoweringandcontrollingthefans(W)

q isthedesignairflowratethroughthesystem,whichshouldbethegreaterofeitherthesupplyorexhaustairflow(l/s).Notethatforanairhandlingunit,qisthelargestsupplyorextractairflowthroughtheunit.

Externalsystempressuredrop means thetotalsystempressuredropexcludingthepressuredropacrosstheairhandlingunit.

10.4 AirdistributionsystemsinnewandexistingbuildingsAirdistributionsystemsinnewandexistingbuildingsshouldmeetthefollowingrecommendedminimumstandards:

a. Airhandlingsystemsshouldbecapableofachievingaspecificfanpowerat25%ofdesignflowratenogreaterthanthatachievedat100%designflowrate.

b. Inordertoaidcommissioningandtoprovideflexibilityforfuturechangesofuse,reasonableprovisionwouldbetoequipwithvariablespeeddrivesthosefansthatareratedatmorethan1100Wandwhichformpartoftheenvironmentalcontrolsystems,includingsmokecontrolfansusedforcontrolofoverheating.Theprovisionisnotapplicabletosmokecontrolfansandsimilarventilationsystemsonlyusedinabnormalcircumstances.

42 BSEN13779:2007Ventilation for non-residential buildings. Performance requirements for ventilation and room-conditioning systems.



58


c. Inordertolimitairleakage,ventilationductworkshouldbemadeandassembledsoastobereasonablyairtight.Waysofmeetingthisrequirementwouldbetocomplywiththespecificationsgivenin:

i. B&ESDW/14443.MembershipoftheB&ESspecialistductworkgrouportheAssociationofDuctworkContractorsandAlliedServicesisonewayofdemonstratingsuitablequalifications,or

ii. BritishStandardssuchasBSEN1507:200644,BSEN12237:200345andBSEN13403:200346.

d. Inordertolimitairleakage,airhandlingunitsshouldbemadeandassembledsoastobereasonablyairtight.WaysofmeetingthisrequirementwouldbetocomplywithClassL2airleakagegiveninBSEN1886:200747.

e. ThespecificfanpowerofairdistributionsystemsatthedesignairflowrateshouldbenoworsethaninTable35fornewandexistingbuildings.Specificfanpowerisafunctionofthesystemresistancethatthefanhastoovercometoprovidetherequiredflowrate.BSEN13779TableA8providesguidanceonsystempressuredrop.Tominimisespecificfanpoweritisrecommendedthatthe‘lowrange’isusedasadesigntarget.

f. WheretheprimaryairandcoolingisprovidedbycentralplantandbyanairdistributionsystemthatincludestheadditionalcomponentslistedinTable36,theallowedspecificfanpowersmaybeincreasedbytheamountsshowninTable36toaccountfortheadditionalresistance.

g. AminimumcontrolspackageshouldbeprovidedinnewandexistingbuildingsasinTable37.

h. VentilationfansdrivenbyelectricmotorsshouldcomplywithEuropeanCommissionRegulationNo327/2011implementingDirective2009/125/ECwithregardtoecodesignrequirementsforfansdrivenbymotorswithanelectricinputpowerbetween125Wand500kW.

43 DuctworkSpecificationDW/144Specifications for sheet metal ductwork. Low, medium and high pressure/velocity air system,B&ES,2013.44 BSEN1507:2006Ventilation for buildings. Sheet metal air ducts with rectangular section. Requirements for strength and leakage.45 BSEN12237:2003Ventilation for buildings. Ductwork. Strength and leakage of circular sheet metal ducts.46 BSEN13403:2003Ventilation for buildings. Non-metallic ducts. Ductwork made from insulation ductboards.47 BSEN1886:2007Ventilation for buildings. Air handling units. Mechanical performance.



59


Table 35 Maximum specific fan power in air distribution systems in new and existing buildings

System type SFP(W/(l.s))

New buildings

Existing buildings

Centralbalancedmechanicalventilationsystemwithheatingandcooling 1.6 2.2

Centralbalancedmechanicalventilationsystemwithheatingonly 1.5 1.8

Allothercentralbalancedmechanicalventilationsystems 1.1 1.6

Zonalsupplysystemwherefanisremotefromzone,suchasceilingvoidorroof-mountedunits

1.1 1.4

Zonalextractsystemwherefanisremotefromzone 0.5 0.5

Zonalsupplyandextractventilationunits,suchasceilingvoidorroofunitsservingsingleroomorzonewithheatingandheatrecovery

1.9 1.9

Localbalancedsupplyandextractventilationsystemsuchaswall/roofunitsservingsingleareawithheatrecovery

1.6 1.6

Localsupplyorextractventilationunitssuchaswindow/wall/roofunitsservingsinglearea(e.g.toiletextract)

0.3 0.4

Otherlocalventilationsupplyorextractunits 0.5 0.5

FanassistedterminalVAVunit 1.1 1.1

Fancoilunit(ratingweightedaverage*) 0.5 0.5

Kitchenextract,fanremotefromzonewithgreasefilter 1.0 1.0

*Theratingweightedaverageiscalculatedbythefollowingformula:

Pmains,1

SFP1P

mains,2SFP

2P

mains,3SFP

3...

Pmains,1

Pmains,2

Pmains,3

...

wherePmains

isusefulpowersuppliedfromthemainsinW.

Table 36 Extending specific fan power for additional components in new and existing buildings

Component SFP(W/(l.s))

Additionalreturnfilterforheatrecovery +0.1

HEPAfilter +1.0

Heatrecovery–thermalwheelsystem +0.3

Heatrecovery–othersystems +0.3

Humidifier/dehumidifier(airconditioningsystem) +0.1



60


Example:

Foracentralmechanicalventilationsystemwithheatingandcooling,andheatrecoveryviaaplateheatexchangerplusreturnfilter:

SFP 1.60.30.1W/(l.s)

2.0W/(l.s)

Table 37 Recommended minimum controls for air distribution systems in new and existing buildings from BS EN 15232:201248

System type Controls package

Central mechanical ventilation with heating, cooling or heat recovery

Airflowcontrolatroomlevel Timecontrol

Airflowcontrolatairhandlerlevel On/offtimecontrol

Heatexchangerdefrostingcontrol Defrostcontrolsothatduringcoldperiodsicedoesnotformontheheatexchanger

Heatexchangeroverheatingcontrol Overheatingcontrolsothatwhenthesystemiscoolingandheatrecoveryisundesirable,theheatexchangerisstopped,modulatedorbypassed

Supplytemperaturecontrol Variablesetpointwithoutdoortemperaturecompensation

Central mechanical ventilation with heating or heat recovery

Airflowcontrolatroomlevel Timecontrol

Airflowcontrolatairhandlerlevel On/offtimecontrol

Heatexchangerdefrostingcontrol Defrostcontrolsothatduringcoldperiodsicedoesnotformontheheatexchanger

Heatexchangeroverheatingcontrol Overheatingcontrolsothatwhenthesystemiscoolingandheatrecoveryisundesirable,theheatexchangerisstopped,modulatedorbypassed

Supplytemperaturecontrol Demandcontrol

Zonal Airflowcontrolatroomlevel On/offtimecontrol

Airflowcontrolatairhandlerlevel Nocontrol

Supplytemperaturecontrol Nocontrol

Local Airflowcontrolatroomlevel On/off

Airflowcontrolatairhandlerlevel Nocontrol

Supplytemperaturecontrol Nocontrol

48 BSEN15232:2012Energy performance of buildings. Impact of building automation, controls and building management.



61


10.5 HeatrecoveryinairdistributionsystemsinnewandexistingbuildingsAirsupplyandextractventilationsystemsincludingheatingorcoolingshouldbefittedwithaheatrecoverysystem.Theapplicationofaheatrecoverysystemisdescribedin6.5ofBSEN13053:2006+A1:201149.Themethodsfortestingair-to-airheatrecoverydevicesaregiveninBSEN308:199750.

Theminimumdryheatrecoveryefficiencywithreferencetothemassflowratio1:1shouldbenolessthanthatrecommendedinTable38.

Table 38 Recommended minimum dry heat recovery efficiency for heat exchangers in new and existing buildings

Heat exchanger type Dry heat recovery efficiency (%)

Plateheatexchanger 50

Heatpipes 60

Thermalwheel 65

Runaroundcoil 45

10.6 CalculatingthespecificfanpowerforSBEMSBEMassumesavalueofSFPforthefancoilsystem,sothisfigureshouldnotbeaddedtotheSFPforthefancoilunitswhenenteringthedataintoSBEM.

HEPAfiltrationisrecognisedasanoptioninSBEM.ThepressuredropcanbespecifiedorSBEMwillassumeadefaultvaluefromtheNCMactivitydatabase.

49 BSEN13053:2006+A1:2011Ventilation for buildings. Air handling units. Rating and performance for units, components and sections.50 BSEN308:1997Heat exchangers. Test procedures for establishing the performance of air to air and flue gases heat recovery devices.



62


Section11:Pipeworkandductworkinsulation

11.1IntroductionThissectiongivesguidanceoninsulatingpipeworkandductingservingspaceheating,hotwaterandcoolingsystemsinnewandexistingbuildingstomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.

Theinsulationofpipeworkandductingisessentialtominimiseheatingsystemheatlossesandcoolingsystemheatgains.Forcoolingsystems,itisalsoimportanttoensurethattheriskofcondensationisadequatelycontrolled.

11.2ScopeofguidanceTheguidanceinthissectioncoversinsulationforthefollowingtypesofpipeworkandductworkservingspaceheating,domestichotwaterandcoolingsystems:

• pipework:directhotwater,low,mediumandhightemperatureheating,andcooled

• ductwork:heated,cooledanddual-purposeheatedandcooled.

11.3InsulationofpipesandductsinnewandexistingbuildingsInsulationofpipesandductsservingheatingandcoolingsystemsshouldmeetthefollowingrecommendedminimumstandards.TherelevantstandardforcalculatinginsulationthicknessisBSENISO12241:200851.

a. Direct hot water and heating pipework

i. Pipeworkservingspaceheatingandhotwatersystemsshouldbeinsulatedinallareasoutsideoftheheatedbuildingenvelope.Inaddition,pipesshouldbeinsulatedinallvoidswithinthebuildingenvelopeandwithinspaceswhichwillnormallybeheated,ifthereisapossibilitythatthosespacesmightbemaintainedattemperaturesdifferenttothosemaintainedinotherzones.Theguidingprinciplesarethatcontrolshouldbemaximisedandthatheatlossfromuninsulatedpipesshouldonlybepermittedwheretheheatcanbedemonstratedas‘alwaysuseful’.

ii. Inordertodemonstratecompliance,theheatlossesshowninTable39fordifferentpipesizesandtemperaturesshouldnotbeexceeded.

b. Cooling pipework

i. Coolingpipeworkshouldbeinsulatedalongitswholelengthinordertoprovidethenecessarymeansoflimitingheatgain.Controlshouldbemaximisedandheatgaintouninsulatedpipesshouldonlybepermittedwheretheproportionofthecoolingloadrelatingtodistributionpipeworkisproventobelessthan1%oftotalload.

ii. Inordertodemonstratecompliance,theheatgainsinTable40fordifferentpipesizesandtemperaturesshouldnotbeexceeded.

iii. AlthoughunrelatedtomeetingrelevantenergyefficiencyrequirementsintheBuildingRegulations,provisionshouldalsobemadeforcontrolofcondensationbyfollowingTIMSAguidance52.

51 BSENISO12241:2008.Thermal insulation for building equipment and industrial installations. Calculation rules.52 TIMSAHVAC guidance for achieving compliance with Part L of the Building Regulations.



63

Section 11: Pipework and ductwork insulation

c. Heating and cooling ductwork

i. Ductingshouldbeinsulatedalongitswholelengthinordertoprovidethenecessarymeansoflimitingheatgainsorheatlosses.

ii. TheheatlossesorgainsperunitareashouldnotexceedthevaluesinTable41.Whereductingmaybeusedforbothheatingandcooling,thelimitsforchilledductingshouldbeadoptedsincethesearemoreonerous.(Heatgainsareshownasnegativevalues.)

iii. Aswithpipework,additionalinsulationmayberequiredtoprovideadequatecondensationcontrol,asdetailedinTIMSAguidance.

Table 39 Recommended maximum heat losses for direct hot water and heating pipes

Heat loss (W/m)

Outside pipe diameter (mm) Hot water[1]

Low temperature heating[2]

Medium temperature heating[3]

High temperature heating[4]

95°C 96°Cto120°C 121°Cto150°C

17.2 6.60 8.90 13.34 17.92

21.3 7.13 9.28 13.56 18.32

26.9 7.83 10.06 13.83 18.70

33.7 8.62 11.07 14.39 19.02

42.4 9.72 12.30 15.66 19.25

48.3 10.21 12.94 16.67 20.17

60.3 11.57 14.45 18.25 21.96

76.1 13.09 16.35 20.42 24.21

88.9 14.58 17.91 22.09 25.99

114.3 17.20 20.77 25.31 29.32

139.7 19.65 23.71 28.23 32.47

168.3 22.31 26.89 31.61 36.04

219.1 27.52 32.54 37.66 42.16

273.0 32.40 38.83 43.72 48.48

NoteToensurecompliancewiththemaximumheatlosscriteria,insulationthicknessesshouldbecalculatedaccordingtoBSENISO12241usingstandardisedassumptions:[1] Horizontalpipeat60°Cinstillairat15°C[2] Horizontalpipeat75°Cinstillairat15°C[3] Horizontalpipeat100°Cinstillairat15°C[4] Horizontalpipeat125°Cinstillairat15°C



64


Table 40 Recommended maximum heat gains for cooled water supply pipes

Outside diameter of steel pipe on which insulation has been based (mm)

Heat gain (W/m)

Temperature of contents (°C)

10[1] 4.9 to 10.0[2] 0 to 4.9[3]

17.2 2.48 2.97 3.47

21.3 2.72 3.27 3.81

26.9 3.05 3.58 4.18

33.7 3.41 4.01 4.60

42.4 3.86 4.53 5.11

48.3 4.11 4.82 5.45

60.3 4.78 5.48 6.17

76.1 5.51 6.30 6.70

88.9 6.17 6.90 7.77

114.3 7.28 8.31 9.15

139.7 8.52 9.49 10.45

168.3 9.89 10.97 11.86

219.1 12.27 13.57 14.61

273.0 14.74 16.28 17.48

NoteToensurecompliancewiththemaximumheatgaincriteria,insulationthicknessesshouldbecalculatedaccordingtoBSENISO12241usingstandardisedassumptions:[1] Horizontalpipeat10°Cinstillairat25°C[2] Horizontalpipeat5°Cinstillairat25°C[3] Horizontalpipeat0°Cinstillairat25°C

Table 41 Recommended maximum heat losses and gains for insulated heating, cooling and dual-purpose ducts

Heating duct[1] Dual-purpose duct[2] Cooling duct[3]

Heattransfer(W/m2) 16.34 -6.45 -6.45

NoteToensurecompliancewithmaximumheattransfercriteria,insulationthicknessesshouldbecalculatedaccordingtoBSENISO12241usingstandardisedassumptions:[1] Horizontalductat35°C,with600mmverticalsidewallinstillairat15°C[2] Horizontalductat13°C,with600mmverticalsidewallinstillairat25°C[3] Horizontalductat13°C,with600mmverticalsidewallinstillairat25°C



65

Section 12: Lighting

Section12:Lighting

12.1 IntroductionThissectionprovidesguidanceonspecifyinglightingfornewandexistingnon-domesticbuildingstomeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.Therearetwoalternativeapproaches,applicablebothtosystemsinnewbuildingsandtoreplacementsystemsinexistingbuildings.

12.2 ScopeofguidanceTheguidanceinthissectionappliestothefollowingtypesoflighting:

• generalinteriorlighting

• displaylighting.

12.3 KeytermsOfficearea means aspacethatinvolvespredominantlydesk-basedtasks–e.g.aclassroom,seminarorconferenceroom.

Daylitspace meansanyspace:

a. within6mofawindowwall,providedthattheglazingareaisatleast20%oftheinternalareaofthewindowwall

b. belowrooflights,providedthattheglazingareaisatleast10%ofthefloorarea.

Thenormallighttransmittanceoftheglazingshouldbeatleast70%;ifthelighttransmittanceisbelow70%,theglazingareashouldbeincreasedproportionatelyforthespacetobedefinedasdaylit.

Spaceclassification forcontrolpurposes53:

Ownedspace means aspacesuchasasmallroomforoneortwopeoplewhocontrolthelighting–e.g.acellularofficeorconsultingroom.

Sharedspace means amulti-occupiedarea–e.g.anopen-planofficeorfactoryproductionarea.

Temporarilyownedspace means aspacewherepeopleareexpectedtooperatethelightingcontrolswhiletheyarethere–e.g.ahotelroomormeetingroom.

Occasionallyvisitedspace means aspacewherepeoplegenerallystayforarelativelyshortperiodoftimewhentheyvisitthespace–e.g.astoreroomortoilet.

Unownedspace means aspacewhereindividualusersrequirelightingbutarenotexpectedtooperatethelightingcontrols–e.g.acorridororatrium.

Managedspace means aspacewherelightingisunderthecontrolofaresponsibleperson–e.g.ahotellounge,restaurantorshop.

Localmanualswitching meansthatthedistanceonplanfromanylocalswitchtotheluminaireitcontrolsshouldgenerallybenotmorethan6m,ortwicetheheightofthelightfittingabovethefloorifthisisgreater.Wherethespaceisadaylitspaceservedbysidewindows,theperimeterrowoflightingshouldingeneralbeseparatelyswitched.

53 ThesedefinitionsaregiveninmoredetailinBREInformationPaperIP6/96People and lighting controlsandBREDigest498Selecting lighting controls.



66


Photoelectriccontrol isatypeofcontrolwhichswitchesordimslightinginresponsetotheamountofincomingdaylight.

Presencedetection isatypeofcontrolwhichswitchesthelightingonwhensomeoneentersaspace,andswitchesitoff,ordimsitdown,afterthespacebecomesunoccupied.

Absencedetection isatypeofcontrolwhichswitchesthelightingoff,ordimsitdown,afterthespacebecomesunoccupied,butwhereswitchingonisdonemanually.

Lamplumens means thesumoftheaverageinitial(100hour)lumenoutputofallthelampsintheluminaire.

Circuit-watt isthepowerconsumedinlightingcircuitsbylampsand,whereapplicable,theirassociatedcontrolgear(includingtransformersanddrivers)andpowerfactorcorrectionequipment.

Lamplumenspercircuit-watt isthetotallamplumenssummedforallluminairesintherelevantareasofthebuilding,dividedbythetotalcircuit-wattsforalltheluminaires.

LOR isthelightoutputratiooftheluminaire,whichmeanstheratioofthetotallightoutputoftheluminaireunderstatedpracticalconditionstothatofthelamporlampscontainedintheluminaireunderreferenceconditions.

Luminairelumenspercircuit-watt isthe(lamplumensLOR)summedforallluminairesintherelevantareasofthebuilding,dividedbythetotalcircuit-wattsforalltheluminaires.

LENI(LightingEnergyNumericIndicator)isameasureoftheperformanceoflightingintermsofenergypersquaremetreperyear(kWh/m2/year),basedonBSEN15193:2007Energy performance of buildings. Energy requirements for lighting.

12.4 Lightinginnewandexistingbuildingsa. Lightinginnewandexistingbuildingsshouldmeettherecommendedminimumstandardsfor:

i. efficacy(averagedoverthewholeareaoftheapplicabletypeofspaceinthebuilding)andcontrolsinTable42

OR

ii. theLENIinTable44.TheLENIshouldbecalculatedusingtheproceduredescribedinSection12.5.

b. ThelightingshouldbemeteredtorecorditsenergyconsumptioninaccordancewiththeminimumstandardsinTable43.

c. LightingcontrolsinnewandexistingbuildingsshouldfollowtheguidanceinBREDigest498Selecting lighting controls.Displaylighting,whereprovided,shouldbecontrolledondedicatedcircuitsthatcanbeswitchedoffattimeswhenpeoplewillnotbeinspectingexhibitsormerchandise,orbeingentertained.



67


Table 42 Recommended minimum lighting efficacy with controls in new and existing buildings

General lighting in office, industrial and storage spaces

Initial luminaire lumens/circuit-watt

60

Controls Control factor Reduced luminaire lumens/circuit-watt

a daylitspacewithphoto-switchingwithorwithoutoverride

0.90 54

b daylitspacewithphoto-switchinganddimmingwithorwithoutoverride

0.85 51

c unoccupiedspacewithautoonandoff 0.90 54

d unoccupiedspacewithmanualonandautooff 0.85 51

e spacenotdaylit,dimmedforconstantilluminance 0.90 54

ac 0.80 48

ad 0.75 45

bc 0.75 45

bd 0.70 42

ec 0.80 48

ed 0.75 45

Generallightinginothertypesofspace Theaverageinitialefficacyshouldbenotlessthan60lamplumenspercircuit-watt

Displaylighting Theaverageinitialefficacyshouldbenotlessthan22lamplumenspercircuit-watt

Table 43 Recommended minimum standards for metering of general and display lighting in new and existing buildings

Standard

Metering for general or display lighting

a. kWhmetersondedicatedlightingcircuitsintheelectricaldistribution,orb. localpowermetercoupledtoorintegratedinthelightingcontrollersofalightingor

buildingmanagementsystem,orc. alightingmanagementsystemthatcancalculatetheconsumedenergyandmakethis

informationavailabletoabuildingmanagementsystemorinanexportablefileformat.(Thiscouldinvolveloggingthehoursrunandthedimminglevel,andrelatingthistotheinstalledload.)



68


12.5 LightingEnergyNumericIndicator(LENI)AnalternativetocomplyingwiththeefficacystandardsinTable42istofollowtheLightingEnergyNumericIndicator(LENI)method.

TheLENImethodcalculatestheperformanceoflightingintermsofenergypersquaremetreperyear.TheapproachdescribedbelowmustbefollowedincalculatingtheLENIforalightingscheme.TheLENIshouldnotexceedthelightingenergylimitspecifiedinTable44foragivenilluminanceandhoursrun.

Design the lighting

Thefirststeptoenergyefficientlightingistodesignthelightinginstallationinawaythatmeetsalloftheusers’needsforthespaceunderconsideration.RecommendationsforappropriateilluminancevaluesandotherlightingrequirementsmaybefoundinBSEN12464-1:201154,andintheSocietyofLightandLighting(SLL)Code for Lighting. The SLL Lighting Handbookprovidespracticaladviceonhowtodesignlightingforanumberofdifferentapplications55.

Look up the lighting energy limit

Indesigningthelighting,alevelofilluminancewillhavebeenselectedasnecessaryforthetasksbeingdoneinaparticulararea.Itisalsonecessarytodeterminehowmanyhoursperyearthelightingwillbeneeded.OnceboththeilluminanceandthehoursareknownitispossibletolookupthelightingenergylimitinTable44.Forexample,aclassroominaschoolmaybelitto300luxandusedfor40hoursperweekfor39weeksoftheyear,givingatotalof1560hoursperyear.Valuesof1500hoursand300luxgivealightingenergylimitof7.70.Table44alsogivesday-time(Td

)andnight-time(Tn)hourvalueswhichare

usedinthecalculationofenergyconsumption.

Ifdisplaylightingisused,thenthelightingenergylimitmaybeincreasedbythevaluegivenfornormaldisplaylightingfortheareaoftheroomwheredisplaylightingisused.Forexample,inanentranceareaforabuildingtheremaybesomedisplaylightinginasmallareaaroundthereceptiondeskbutnotintherestofthearea.

Shopwindowsusealotofdisplaylightingandmayuseupto192.72kWh/m2/yearifthewindowfacesapublicroad,and96.8kWh/m2/yearifthewindowisinashoppingcentrethatisclosedduringthenight.

Calculate the parasitic energy use (Ep)

Ifsomeformoflightingcontrolsystemisused,thenanallowanceneedstobemadefortheenergyusedbythecontrolsystem,andthefactthattheluminairestakealittlepowereveniftheyaredimmeddowntogivenolight.Anallowanceof0.3W/m2shouldbemadeforpowerusedinthisway.Ifthewholelightingsystemisswitchedoffwhentheroomisnotinuse,thenthepowerlossisonlyduringthehoursofuse.Ifthesystemisleftonallthetimethenthepowerlossoccursfor8760hoursperyear.

Ifnolightingcontrolsystemisused,thentheparasiticenergyuseiszero.

Determine the total power of lighting (Pl)

Thisisthetotalpowerinwattsconsumedbytheluminaireswithinaspace.

54 BSEN12464-1:2011. Light and lighting. Lighting of work places. Indoor work places.55 Forfurtherinformation,seewww.sll.org.ukandwww.thelia.org.uk.



69


Determine the occupancy factor (Fo)

Foallowsforthefactthatenergyissavedifanautomaticcontrolsystemdetectsthepresenceorabsence

ofpeopleinaroomandswitchesoffthelightswhenthereisnobodyusingtheroom.Ifnoautomaticcontrolisused,thentheoccupancyfactorF

o1.Ifcontrolsturnoffthelightswithin20minutesofthe

roombeingempty,thenFo0.8.

Determine the factor for daylight (Fd)

Fdallowsforthefactthatifthelightingisdimmeddownwhenthereisdaylightavailable,thenless

energywillbeused.Ifnodaylight-linkeddimmingsystemisused,thenFd1.Iftheelectriclightingdims

inresponsetodaylightbeingavailable,theninareaswithadequatedaylightFd0.8.Adequatedaylight

maybefoundinareasthatarewithin6mofawindowwallorinareaswhere10%ormoreoftheroofistranslucentormadeupofrooflights.

Determine the constant illuminance factor (Fc)

Whenlightingisdesigned,amaintenancefactor(MF)isusedtoallowforthefactthatasthelightingsystemagesitproduceslesslight.Thismeansthatondayonethelightingsystemisprovidingmorelightthanneeded.Thuswithaconstantilluminancesystem,itispossibletounder-runthelightingondayone,andthenslowlyincreasethepowerusedbythelightinguntilthepointisreachedwhenmaintenanceneedstobecarriedoutbychangingthelampsorcleaningtheluminaires.SystemsthatcontrolthelightinginthiswayhaveanFc

0.9,andthosethatdonothaveanFc1.

Calculate the daytime energy use (Ed)

Thedaytimeenergyuseis:

Ed PlFoFdFcTd

1000

Calculate the night-time energy use (En)

Thenight-timeenergyuseis:

En PlFoFcTn

1000

Calculate total energy (kWh) per square metre per year (LENI)

Thetotalenergypersquaremetreperyearisthesumofthedaytime,night-timeandparasiticenergyusesperyeardividedbythearea(A),assetoutintheformulabelow:

LENI EpEdEn

A



70


Table 44 Recommended maximum LENI (kWh per square metre per year) in new and existing buildings

Hours Illuminance (lux) Display lighting

Total Day Night 50 100 150 200 300 500 750 1000 NormalShopwindow

1000 821 179 1.11 1.92 2.73 3.54 5.17 8.41 12.47 16.52 10.00

1500 1277 223 1.66 2.87 4.07 5.28 7.70 12.53 18.57 24.62 15.00

2000 1726 274 2.21 3.81 5.42 7.03 10.24 16.67 24.70 32.73 20.00

2500 2164 336 2.76 4.76 6.77 8.78 12.79 20.82 30.86 40.89 25.00

3000 2585 415 3.31 5.72 8.13 10.54 15.37 25.01 37.06 49.12 30.00

3700 3133 567 4.09 7.08 10.06 13.04 19.01 30.95 45.87 60.78 37.00

4400 3621 779 4.89 8.46 12.02 15.59 22.73 37.00 54.84 72.68 44.00 96.80

5400 4184 1216 6.05 10.47 14.90 19.33 28.18 45.89 68.03 90.17 54.00

6400 4547 1853 7.24 12.57 17.89 23.22 33.87 55.16 81.79 108.41 64.00

8760 4380 4380 10.26 17.89 25.53 33.16 48.43 78.96 117.12 155.29 87.60 192.72



71

Section 13: Heating and cooling system circulators and water pumps

Section13:Heatingandcoolingsystemcirculatorsandwaterpumps13.1 IntroductionHeatingandcoolingwaterinHVACsystemsofnon-domesticbuildingscancirculateforextensiveperiodsandberesponsibleforconsiderableenergyuse.

13.2 ScopeofguidanceThissectionprovidesguidanceonspecifying:

• heatingsystemglandlesscirculators,bothstandaloneandintegratedinproducts

• heatingandcoolingsystemwaterpumps

tolimittheirenergyconsumptionandmeetrelevantenergyefficiencyrequirementsintheBuildingRegulations.Theguidancecoverscirculatorsandwaterpumpswhenusedinclosedsystems.

13.3 KeytermsHeatingsystemglandlesscirculator means apumpusedtocirculatehotwaterinclosedcircuitheatingsystems.Theglandless(orwetrotor)circulatorisacentrifugalpumpwithanintegralmotorandnomechanicalseal.Itcanhaveanintegratedmotordriveunitforvariablespeedoperation.

Waterpump (alsoknownas‘dryrotor’or‘directcoupled’pump) means acentrifugalpumpdrivenbyanelectricmotorandgenerallyhavingmechanicalseals.Commonpumptypesincludein-line,endsuctionandverticalmulti-stage.Thefirsttwoareusuallysingle-stagepumpshavingsingle-entryvolute.BydesigntheycanallbeusedascirculatorsforallHVACapplicationsdependingonconfigurationandduty.

13.4 GlandlesscirculatorsandwaterpumpsinnewandexistingbuildingsHeatingsystemglandlesscirculatorsandheatingandcoolingsystemwaterpumpsinnewandexistingbuildingsshouldmeettherecommendedminimumstandardsinTable45.

Table 45 Recommended minimum standards for heating system glandless circulators and heating and cooling system water pumps in new and existing buildings

a. InaccordancewithEuropeanCommissionRegulationNo622/2012(amending641/2009)implementingDirective2009/125/ECwithregardtoecodesignrequirementsforglandlesscirculatorsupto2.5kW:

i. From1January2013,standaloneglandlesscirculators,otherthanthosespecificallydesignedforprimarycircuitsofthermalsolarsystemsandofheatpumps,shouldhaveanEnergyEfficiencyIndex(EEI)nogreaterthan0.27.

ii. From1August2015,standaloneglandlesscirculatorsandglandlesscirculatorsintegratedinproductsshouldhaveanEnergyEfficiencyIndex(EEI)nogreaterthan0.23.

b. Variablespeedglandlesscirculatorsshouldbeusedonvariablevolumesystems.

c. WaterpumpsshouldcomplywiththerequirementsofEuropeanCommissionRegulationNo547/2012implementingDirective2009/125/ECwithregardtoecodesignrequirementsforwaterpumps.

d. Ifawaterpumpisusedonaclosedloopcircuitandthemotorisratedatmorethan750W,thenitshouldbefittedwithorcontrolledbyanappropriatevariablespeedcontrolleronanyvariablevolumesystem.Onwaterpumpboostersetswithanopenloopcircuit,thestaticheadshouldbecheckedbeforeanappropriatevariablespeedcontrollerisused.


Furtherinformationandguidanceisavailablefromwww.bpma.org.ukwherealistofapprovedglandlesscirculatorsandwaterpumpscanbefound.



72


AppendixA:Abbreviations

BER BuildingcarbondioxideemissionrateBMS BuildingmanagementsystemBS BritishStandardCHP CombinedheatandpowerCHPQA CombinedHeatandPowerQualityAssuranceCO

2 Carbondioxide

COP CoefficientofperformanceDCLG DepartmentforCommunitiesandLocalGovernmentDECC DepartmentofEnergyandClimateChangeDHW DomestichotwaterEEI EnergyEfficiencyIndexEER EnergyefficiencyratioEN EuropeanNorm(standard)ESEER EuropeanSeasonalEnergyEfficiencyRatioHEPA High-efficiencyparticulateabsorptionHVAC Heating,ventilationandairconditioningLENI LightingEnergyNumericIndicatorLPG LiquifiedpetroleumgasMF MaintenancefactorNCM NationalCalculationMethodologyPSEER PlantseasonalenergyefficiencyratioQI QualityindexRHI RenewableHeatIncentiveSAP StandardAssessmentProcedureSBEM SimplifiedBuildingEnergyModelSCOP SeasonalcoefficientofperformanceSEER SeasonalenergyefficiencyratioSFP SpecificfanpowerSI StatutoryInstrumentSPEER SeasonalprimaryenergyefficiencyratioSPF SeasonalperformancefactorTER TargetcarbondioxideemissionrateTRV ThermostaticradiatorvalveVAV Variableairvolume





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