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IFoughttheLaw(andtheLawWon)
I'mbreakin'rocksinthehotsunIfoughtthelawandthelawwonIfoughtthelawandthelawwon
Ineededmoney'cause IhadnoneIfoughtthelawandthelawwonIfoughtthelawandthelawwon
IleftmybabyandIfeelsosadIguessmyraceisrunButshe'sthebestgirlI'veeverhadIfoughtthelawandthelawwonIfoughtthelawandthelawwon
WrittenbySonnyCurtisfromBuddyHolly’sgroup,sungbyBobbyFuller
Thesecondlawthatis.
Robbin'peoplewithasix-gunIfoughtthelawandthelawwonIfoughtthelawandthelawwon
ImissmybabyandthegoodfunIfoughtthelawandthelawwonIfoughtthelawandthelawwon
IleftmybabyandIfeelsosadIguessmyraceisrunButshe'sthebestgirlI'veeverhadIfoughtthelawandthelawwonIfoughtthelawandthelawwon
01'2-$3*- ++5+50.4#E F$G*9*.*,+.$,2$H0'&#(D;/,&E I./(%4*.0'6$*+$JKLLE M(6'$*+$M(6*.,+@$:!E :'$.?'-*(4*N'$*+$6'01#*6*2*-(/*,+$O$0'(/$&'-4(*#$?&,61-/.E P*,+''&.$,2$50,4'D0,1.'$6'01#*6*2*'&.$(+6$-&(54$.?(-'$6'01#*6*2*'&.
Before
After
Before
After
SecondLaw
• HightoLow
• WarmtoCold
• WettoDry
ButwhataretheotherLaw’sofThermodynamics?
“Allenergydeservesthesameentropy!”
LawsofThermodynamics
NeilMoyer(andsomedeadguys)Thermodynamicsisafunnysubject:• Thefirsttimeyougothroughit,youdon'tunderstanditatall.
• Thesecondtimeyougothroughit,youthinkyouunderstandit
• Thethirdtimeyougothroughit,youknowyoudon'tunderstandit,butbythattimeyouaresousedtoit,youdon’tcareanymore.
HistoryofThermodynamics
• 1824Sadi Carnot:Cycle,TSourceandTSink– ThermalEfficiency
• 1850RudolfClausius:Heatcannot,ofitself,passfromalowertoahighertemperature.Entropy.2nd Law
• 1852WilliamThomson(LordKelvin):AbsoluteTemperature.
• 1906WaltherNernst:Entropyatabsolutezeroisaconstant.3rd Law
• 1935RalphFowlernamesZerothLaw
LawsofThermodynamics•1st – Energycanbeneithercreatednordestroyed;onlyconverted.
•2nd – Theavailableenergyoftheisolatedsystemdecreasesinallrealprocesses(andisconservedinreversibleprocesses).
•3rd – theentropyofapuresubstanceincompletethermodynamicequilibriumbecomeszeroattheabsolutezerooftemperature
• Zeroth:Ifabodyisinequilibriumwithtwoothers,theyareinequilibriumwitheachother.
LawsofThermodynamics
• Youcan’twin
• Youcan’tevenbreakeven
•Andyoucan’tgetoutofthegame.
•Heavyweightsfighttoadraw.
WhatWeNeedtoKnow
•1st: ConservationofEnergy
•2nd : Entropyincreases,availableenergydecreasesinrealprocesses.
•3rd : Absolutezerocannotbeattained.
• Zeroth: noDT,noDQ.
BasicRefrigeration
BasicRefrigeration
Cycle
BasicRefrigeration
Cycle
CarnotAxiom:
Acyclenotreceivingworkcannottransferheatfromthecoldtothehotreservoir.
BasicRefrigeration
Cycle
GrossHeatRejection
IfCooling:GHRis“gross”– waste
IfHeating:GHRis“gold”– theendproduct
12,000BTUH3,000BTUH=4.0C.O.P.
Cooling
15,000BTUH3,000BTUH=5.0C.O.P.
Heating
CoefficientofPerformance
EPAMileageforAirConditionersWecanuseC.O.P.as“EPAMileage”(ButI’mtoolazytoconvertWattstoBTUH,so…)12,000Apples1,000Orangesx1,000=12.0Apples/Orangesx1,000OR• 12.0EnergyEfficiencyRatio=12.0EER
• Butthat’sjustintown.Howabout“HighwayMileage?”• JustfactorinhowtheA/Cworksatpartloadindifferentseasons,andwehave: SeasonalEnergyEfficiencyRatio(SEER)
• There’snosuchthingasafreethermodynamiclunch.• ThethreebiggestproblemsinbuildingsareWATER,WATER,andWATER.• Whentheraterofentryisgreaterthantherateofremoval,accumulationoccurs.• Don’tbeadope…slope.• DraintheRainMainlyonthePlane.• Ifyouwanttosavecash,flash.• Ifsomeoneinventedwoodtoday,itwouldneverbeapprovedasabuildingmaterial.Itburns,itrots,ithasdifferentpropertiesbaseduponorientation,andworstofallitseesrelativehumidityandnotvaporpressure.
• OBSistheSpamofwood.SPAMistheOSBofluncheonmeats.
WhatWe’veHeard
• Engineeredwoodisaninsulttoengineersandwood.
• CelluloseInsulation:thebestusefortheNewYorkTimes.
• Oldmoldwithnoteethcaneatpaper.
• Greenboard:coloringpapergreentoprotectitfrommoldislikeputtinglipstickonapig.
• Eventhedumbestofthethreelittlepigsdidnotbuildhishouseoutofpaper.
• Thefolksthatcansensevaporpressuredifferencesalsoseedeadpeople.
• ConcentrationGradients– Watermovesfrommoretoless.Youcandothisexperimentathome.Takeadrythingandtouchawetthing.Thedrythingbecomeswet.
• Thereareonlytwokindsofwindowsintheworld…thosethatleakandthosethatwillleak.
• Aleakisnotaleakunlesstheclientseesit.• ASTMstandsfor“AnotherStupidTestingMethod”• Congresssucks.• Don’tfightMotherNature.• Wehavethetechnology.• Moneyfornothin'andthechicksforfree.• Youdon’tgetthedoughunlessyoudotheshow.• BetsyRules.
Sisyphus
“…themaintenanceofdesiredhumiditylimitsundercertainloadconditionsmayonlybepossiblebyusingreheat.”
- WillisCarrier,ModernAirConditioning,1940
Andhewentontosay:
“Oneofthemoreconvenientsourcesofreheatenergyisthehotgasdischargedbytherefrigerantcompressor.”
EvolutionofDehumidification
•1900 CarrierdehumidifiesBrooklynprintingplants•1940 Carrierwritesreheatandhotgasissolution•WWII VaporcompressionDHcycle•1950’s Smalldehumidifiersinbasements•1973 Oilembargo,noreheat,nodehumidification•1990’s KenGehring andothersdevelopwholehouse
dehumidifier
Enthalpy
WetBulb(wb)andEnthalpy(h)• CarrierdiscoveredthatwetbulbtemperaturewasanexcellentindicatorofEnthalpy
Butnotexactly…
• Wenowhavethemeanstocalculateandread-outEnthalpydirectlywitheconomicalinstruments,so…
• wb shouldgoaway;thereisnoneedtomeasure
EnthalpyofMoistAirWorkingDefinition:Energycontentofairduetocombinedeffectofheatandmoisture.
Units:BTU/lbm-DryAir
DATUM:Air- 0ºF.Water- Liquid@32ºF.
Example:Airat75ºF./50%RH/HR=66Gr/lbm DryAirStartWithWater: HeatLiquidH20(55– 32)=
EvaporateWater@55ºF.:HeatVaporto75:.489X(75-55)=SUB-TOTAL,H2O,BTU/lb:
XMassofWater:66/7,000:HeatContentofWater:Thenheatairto75ºF.: .24X(75-0)=
TOTALHEATCONTENT,ORENTHALPY– h:
BTUH /lb.
1062.189.781094.96
X.0094
23.00
10.29+18.0028.29BTUH/lb.
EnthalpyExample
Compare:PsychChart: 28.6BTU/LBMoistAirSaturated62.5ºF.wb: 28.2BTU/LB
HowDoWeIntroduceWarm,DryAir?
•Directlyto/fromthespace•Wholehousedehumidifier– connecttoHVAC•Dedicatedoutdoorairsystem(D.O.A.S.)
•Anddon’tforget…we’redoingreheatsoithastogointotheSupplyair.
D.O.A.S.CanRejectExcessGHR– SplitDehu
DedicatedOutdoorAirSystem(D.O.A.S.)
•By2000:TheDedicatedOutdoorAirSystem•AkaOutdoorAirPre-TreatmentSystem•D.O.A.S.:Sophisticatedrefrigerationcyclethatcoolsanddehumidifiesoutsideairfromsummerdesign92db /79wb downto50ºF.DewPoint(orlower)andreheatsthatairtoroomtemperature,72ºF.(“Neutral”)
•Verysophisticatedcontrolstomodulatecapacityacrosswiderangeofenteringairconditions.
5"L6<:R>)"+./"I33)7(<V)M"?$/%>+(<.&"@$("F+8"B)')+("6;8():
E$<,+/&,4.$(&'$2(-/,&7$-,+2*31&'6$(+6$&'(67$/,$(--'?/$*+?1/.$2&,#$/0'$2*'46$#,1+/'6@$2(-/,&7$?&,9*6'6$.1??47$(*&$/'#?'&(/1&'$.'+.,&$*+$/0'$61-/5,&)@$.1??47$(*&$/'#?'&(/1&'$(+6$&'.'/$.1??47$(*&$/'#?'&(/1&'$G!P$.5*/-0$.'/$?,*+/.@$(+6$2*'46$5*&*+3$,2$($01#*6*./(/$(+6$($2*'46$?&,9*6'6$[DJ[$pG<$.1??47$(*&$/'#?'&(/1&'$&'.'/$.*3+(4U
9')"6R><("6;8():"@%:</<(;"6$>%(<$.
D.O.A.S.– TypicalInstallation
D.O.A.S.– InjecttoReturnAir- Wrong
D.O.A.S.– InjecttoSupplyAir- Correct
D.O.A.S.– WithReturnAir– DehumidifierMode
D.O.A.S.Do’sandDon’ts
Don’t:•Usea splitsystem– noheat•DischargetoAHUinlet– sendsreheattodumpster
Do:•Useaselfcontainedpackageunit—”rooftop”• Injecttreatedairdownstreamofcoolingcoil• Installareturnairconnectionanddehumidistat
TheDoubleWideLabExperience
Icancoolthisdoublewidewith____Tons?
Icancoolthisdoublewidewith…about3tons
It’sanAnimalLab
• 1,000Sq.Ft.LabRequired
• Need100%Standby,so…
• 2X1,000Sq.Ft.=2,000Sq.Ft.
• 20,000CFM• 335CFMPERACH
GuideforUseandCareofLaboratoryAnimals,1996
• 40– 85ºF.• 30– 70%rh• 10-15ACHFreshAir,so• 3,330to5,000CFM• 50%Fresh/50%re=cycled
• HEPAFiltered• (48)Occupants@50BTUH
DidImention100%Standby?
So,whatdidweget?
28 28
28 28
(4)28-TonCondensingUnits(2)56-TonAHU’s
(2)Generators
112 Tons!
HOUSESINSOUTHFLORIDA
Remote MonitoringHouses in South Florida
Single Story - 3 Bedrooms - 2.5 Baths - 2,700 ft2
WhatWeWereTold
•ChangedtoR-38atticinsulation•Noridgevent:Miami/Dadepractice.•ACsupplyinclosets.•AHU’snowinclosets,notinattic.• FullyductedreturntoMER+jumpducts• SoliddoorsonMERfornoisecontrol.
Remote MonitoringHouses in South Florida
Kitchen Air - Above the Cabinets
Remote MonitoringHouses in South Florida
Attic Air Sensors: T + RH + Dpt + gr/lb
Remote Monitoring
Remote MonitoringHouses in South Florida
Sensor on the Ceiling - Inside the Mechanical Closet
Remote Monitoring
Remote MonitoringHouses in South Florida
5<4"Y),"H$<.(8K.)"Y+;"` e%>;"Nf('E"?</.<&'("($"?</.<&'(
Kitchen dew point
Outdoor dew point
Attic dew point
Remote MonitoringHouses in South Florida
5((<7"Y),"H$<.("VJ"Y4;,+>>"6%43+7)"9):R8One Day - July 15th: Midnight to Midnight
Drywall Face Temp.
Attic dew point
Drywall Back Temp.
Remote MonitoringHouses in South Florida
#+7)"V8J"2+7Z"$3"Y4;,+>>"` +0 -0+()4"+7(<V<(;1K.)"Y+;"` e%>;"Nf('E"?</.<&'("($"?</.<&'("` fT\M"&;R8%:"X$+4/"7)<><.&
Face aW
Back aW
Remote MonitoringHouses in South Florida
5((<7"6(4+(<3<7+(<$."-5<4"9):R1K.)"Y+;"` e%>;"Nf('E"?</.<&'("($"?</.<&'(
Drywall (Under Insulation)
Attic air (Near the eave)
Attic air (Near the peak)
Remote MonitoringHouses in South Florida
5((<7"6(4+(<3<7+(<$."-5<4"Y),"H$<.(1K.)"Y+;"` e%>;"Nf('E"?</.<&'("($"?</.<&'(
Attic air (Near the eave)
Attic air (Near the peak)
Remote MonitoringHouses in South Florida
5((<7"6(4+(<3<7+(<$."-5<4"@%:</<(;"B+(<$1K.)"Y+;"` e%>;"Nf('E"?</.<&'("($"?</.<&'(
140 gr/lb (Near the eave)
186 gr/lb (Near the peak)
ASHRAE Design (Sensible)
92F 78wb = 123gr/lbASHRAE Design (Dew Point)
85F 79dpt = 152gr/lb
WhatDidWeLearnFromMonitoring?• Highatticdewpoint,85• Ceilingswereat70ºF.• Backofdrywallwasat72ºF.• Highwateractivity—66face,90ontopsideofceiling• AtticStratification:108ridge,90center,72underinsulation• DewPointStratification;85ridge,75eaves• HumidityRatiostratification:186Grridge,140Greave• Compare:123GrHVACdesign,152Grhumiditydesign.
LewHarriman’sFindings
•Highatticdewpoint•Coldceilingsinclosets,bathrooms,andMER’s•Highsurfacewateractivity
Remote MonitoringHouses in South Florida
9;R<7+>"6%::)4"53()4.$$.e%>;"Nf('"OQNc"+("bEQQR:
Outdoor Air91° + 78 dpt
Attic Air: 106F + 85 dpt
R-38 Insulation(Blown Fiberglass)
Back of Drywall: 72F
Face of Drywall: 71F
Mechanical Closet
Kitchen Air76° + 58 dpt
JoeLstiburek’s Recommendations:
•O’Hagin ridgevents,1:300,50/50%• Fancyclers• Jumpduct:improvecirculation,warmceilings
KU@+&<. B</&)"g).(8
g).()/"5((<7EJTa[[Z[s$;,22*/Z[s$B*63'
HVACDiagram– ReturnAirPath
JumpDuctAdded
HVACDiagram– JumpDuct
A*31&'$W@$?(3'$J_UW$*+$F;=BFI$A1+6(#'+/(4.U P0*4$(+6$H,66$%,/0$,5+$/0(/$%,,)$.0,146$7,1$5(+/$/,$/&7$($%'//'&$.-(+U !$/0*+)$`*))*$0(.$(4&'(67$3,//'+$($%'//'&$*#(3'$2&,#$0'&$6*3*/(4$9'&.*,+$,2$A1+6(#'+/(4.U
8x8GrilleAdded
HVACDiagram– 8x8
Semi-ActiveReturns
HVACDiagram– Semi-ActiveReturnDucts
ReturnAirDuctRemoved
HVACDiagram– FreeReturn
HVACDiagram– IncreaseReturnPath
ReturnGrillAdded
HVACDiagram– TheSolution
DECStatement•Needtowarmceilings.•Removehumidityfromclosetsandbaths.• Semi-ActiveReturnducts(DehumidifierInlets).• Treatairfromclosetsandbathsindehumidifier.•DischargedehumidifiertoA/C.•Approvedbystate,embracedbybuildingofficial.
Tools
"#$%&'"'()*)+,-./)()*)+,0/
*'1+2324#1+,-//
$567897::+)$;<=-1-//-+,->=?//+
SupplyDuctCeilingPenetration
Summary:WhatWeDid•RidgeVents•Dehumidifiers• FanCyclers• TweakedReturnAir
Epilogue:TheDog
CanterburyShakerVillage
Canterbury Shaker Village
RETHINK TRADITION
Vitruvius
• Firmitas• Utiilitas• VenustasOR• Firmness• Commodity• Delight
Shakers
•Useful•Good•Beautiful
ShakerProducts
•Brooms•Buckets• Tubs•Dresses• IvyLeagueSweaters• Furniture
LaundrySteamEngine– WaterCooled
LaundrySteamEngine– AirCooled
ShakerMills
• Saw•Grist• Turning•Carding• ThreshingMachine
ShakerWater- ShaftWork+
• Iceinwinter•Drink•Cook• Laundry• Livestock• Irrigation
ShakerPondSystem
• (7)Ponds•About50acres•2milesofditches•170’fall•1.6%grade
WhatWe’veLearned• I know it as “HOC”, the energy it takes to drive
a refrigeration cycle.
• It’s why 14 SEER A/C’s become 13, not 15 SEER.
• It’s what’s in the dumpster at the end of a construction project.
• It’s why glasses don’t unbreak.
• It’s why stuff doesn’t unburn.
• It’s why 14 socks become 12, not 14.
• It’s why jelly bread always lands jelly side down.
• It’s why I don’t get younger.
• It’s what you leave in the toilet bowl after you go to the bathroom.
Whenyouaredonewithyourenergy,besureitisallwornout!
Fundamentals- HVACFormulas
•1.085xSCFMxDeltaTºF.=BTUH•4.5xSCFMxDeltah– BTU/LB=BTUH•500xGPMxDeltaTºF.=BTUH•R.E.BTUH+H.O.C.BTUH=G.H.R.BTUH•AddaTraneDuctulator andIwasarmedanddangerous
I’vebuiltmycareeron(4)formulas:
R.E.BTUH+H.O.C.BTUH=G.H.R.BTUH
OR
RE+HOC=GHR
12,000BTUH+3,000BTUH=15,000BTUH
RefrigerationMath
TransportingHeatBTU:Heat1.0lb.Water1.0ºF.
TonofCooling:Melt2,000lb.Ice@144BTU/lb.in24hours=12,000BTU/HR=12,000BTUH
EnergyWeBuyattheBTUStore:Watt-HoursX1,000=Kilowatt-Hours=Kwh
ConvertWattstoBUTH:1.0Watt=3.413BTUH 1.0Kw=3,413BTUH
1,000Watts=3,413BTUH=3,000BTUH
InAndymath:
• R.E.=RefrigerationEffect• Transmission• Lights• People• O.A.• A/CLoads• EnergyTransported• RemovedfromColdReservoir
• +H.O.C.=HeatofCompression=CompressorkW+Auxiliaries(Fans&Pumps)
• =G.H.R.=GrossHeatRejection=EnergytransportedtoHotReservoir
• Ifcooling:GHRis“gross”– waste• Ifheating:GHRis“gold”– theendproduct
• R.E.=RefrigerationEffect• Transmission• Lights• People• O.A.• A/CLoads• EnergyTransported• RemovedfromColdReservoir
• +H.O.C.=HeatofCompression• =CompressorkW+Auxiliaries(Fans&Pumps)
• =G.H.R.• =GROSSHEATREJECTION
• =EnergytransportedtoHotReservoir
BuyingEnergyattheBTUStore(akaTHEPOWERCOMPANY)
• HowmuchenergydowebuyattheBTUStore?(akathePowerCompany)
• WehavetobuytheH.O.C.:energythatdrivesthecompressorandauxiliaries
• 1970:ABOUT1.0Kwpertonofcooling.(oldhermetictincancompressorswereworse:upto1.4kWperton)
RefrigerationEfficiencyWecanexpressefficiencyastheratioof:• R.E./H.O.C.– WhatWeGet/WhatWeBuy(HigherisBetter)Or• R.E.÷ H.O.C.andWhatWeGet÷ WhatWeBuy
Inmyexample:• R.E.+H.O.C.=G.H.R.• 12,000BTUH+3,000BTUH=15,000BTUH (About1.0kWperton)• R.E.÷ H.O.C.=12,000÷ 3,000=4.0CoefficientofPerformance(C.O.P.Cooling)
HeatPumpEfficiency
ForHeating:• G.H.R.÷ H.O.C.=15,000÷ 3,000=5.0C.O.P.HeatingAND• C.O.P.Heating ALWAYS=C.O.P.Cooling+1
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