Heating & Ventilation, Air Conditioning & Refrigeration: Chapter 6

OVERVIEW For the purposes of this chapter, building construction will concentrate mainly upon simple industrial/commercial building design and construction. Domestic dwellings are amply covered by other sources but it will be noticed that some of the design technology is very similar and therefore some items are included in the section in traditional buildings.

At the end of this chapter you should be able to:

• list the parts of a simple industrial/commercial building

• state the main functions of the components that make up a simple building

• list the principal services required of a simple building

• list how to gain safe access to services

• describe typical materials found in the MES sector

• describe how to deal with insulating materials found in the MES sector.

Understanding building construction methods and the materials used in the MES sector

133

chapter6

134

Heating and Ventilation, Air Conditioning and Refrigeration

Traditional building constructionIf you have travelled around the United Kingdom you may have noticed that older style industrial/commercial buildings are built of the materials that were close to hand at the time of construction. Hence, in the North of England, Scotland and Wales we have a predominance of buildings erected with granite or sandstone walls, with floors of stone slabs, and roof structures made from timber covered with slate or stone. Southern areas more often use locally produced bricks, with timber roof and floor construction.

Whatever the design and method of construction, all industrial/commercial buildings have the same requirement; that is, a clear unobstructed internal floor area to allow people to move about easily and accommodate office equipment or manufacturing production machinery. Therefore, you may have noticed that older, traditionally built buildings have strong thick walls supporting high roof structures that have wide clear areas underneath. An example of this would be a theatre that has hundreds of seats, all of which require an unobstructed view of the stage.

When looking at the construction of industrial/commercial buildings we need to appreciate the division between traditional building methods and framed building methods in relation to the MES engineer. We will cover the latter in the next section. The installation and maintenance procedures may be different with each type of construction. Visit public buildings in your area and try to imagine how they were built.

Definition

Industrial buildings, e.g. factory, mill, warehouse, store. Commercial buildings, e.g. office, school, theatre, hospital. Can you think of any more examples?

J6990HED Mechanical Eng BW PDFAW_076AW by HL Studios

High rise(over seven storeys)

Semi-detached

Terraced Detached

Medium rise(four to seven storeys)

Low rise(one to three storeys)Figure 6.01 Types of building

135

Chapter 6 Understanding building construction methods and the materials used in the MES sector

Traditional buildings are those that are constructed along the lines of a typical domestic house, but larger. What we see today as a house has evolved over many centuries and, as building materials have improved in quality and availability, they have influenced what the building is constructed from. However, in real terms the features of the domestic house have changed very little, in that we have floors, walls and roofing the same design as in bygone days.

Wall constructionThe walls are there to hold up the roof, keep out water and to keep the occupants warm. Solid walls do this quite well, but are expensive to construct and have to be very thick to stop water from penetrating the building.

We now employ a double wall construction, a wet one on the outside and a dry one on the inside. The gap (or cavity) between the two walls acts as a barrier against damp and provides a measure of heat insulation. The gap is increasingly filled with an insulating material, which retains the original function of the cavity but slows down the transfer of heat from inside to outside, making the building more thermally efficient. A continuous damp proof membrane in the bricks above ground level prevents damp being drawn up the wall.

On the inside, internal walls act in most parts as dividers to segregate each activity of the rooms. They do not require insulation and therefore are made thinner. Their construction could be of brick, plastered over and then decorated, or a timber framework (called studwork), which is covered with plasterboard and then finished off.

HeinemannNVQ2 Plumbing9pt Zurich BTfig05708/07/05

Outline of roof

Facing bricks102.5 mm

Direct glazedwindow frame

Brick externalreveal

Wall tie

DPC

150 mm min.

Weephole

Cavity filling

6 mm cavity closer

Block inner leaf(90 mm min.)

Steel lintel(with insulation)

Internal plasteredreveal

Window board50 or 65 mminsulated cavity

Solid ground floor

DPM

Load-bearingconcrete blocks

Strip foundation

Figure 6.02 Cavity wall section


Clear cavity

Partially filled cavity

Fully filled cavity

Figure 6.03 Cavity wall with insulation


Clear cavity


Fully filled cavity


Clear cavity


Fully filled cavity

136


Ceilings and floorsInternal ceilings in traditional buildings follow a similar construction to timber framed walls, being made of timber joists, cladding and plaster.

Floor construction in domestic buildings comprises floorboards or sheets of chipboard laid over timber joists. Some ground floors are solid, made from concrete on a damp proof membrane and laid over hardcore or of block and beam construction.

Can you identify any other examples where you live?


Ceiling joists

Headplate

Noggins

Soleplate

Folding wedgesagainst wall

Stud

Floor joists

Doublejoist support

Section

Soleplate

75 x 50 mmheadrail

Ceilingjoists

ElevationFlooring

Noggins

600 mm

Plan400 mm

Figure 6.04 Internal wall construction

Did you know?

If you were to look behind the walls of older type properties, you might find the cladding to be strips of wood (laths) nailed to the studding, plastered over and then decorated


Plastic meshsupport

Timber joist

Insulation

Figure 6.05 Timber flooring

137


RoofingIn a cold and wet country the roof keeps out rain and snow. For centuries, a roof constructed on an angle, known as pitched, and covered with slate, tile, stone or metal sheeting, was the most efficient, as it sheds water quickly into gutters at the eaves or lowest edges of the roof. Commercial roof covering can sometimes include decorative finishes like copper, aluminium or lead as well as traditional roof coverings.

There is no typical industrial/commercial building roof, even on traditional buildings. It can be pitched or flat. The only limiting factor is the practical ability to span distances. A roof must be able to support itself, plus any increase in weight brought about by the addition of rain or snow. Short spans could use a traditional timber design but longer spans require a different approach. Medium spans generally utilise the truss roof construction made from steel sections. Longer spans tend to be constructed using reinforced concrete, lattice beam or portal beam construction.


150mm min.

DPC

Pouredconcrete

Sand/cementgrout

Block

Reinforcedconcrete beamReinforcedconcrete beam

150 mm min.

Sand/cement BlockPouredconcrete

DPC

Reinforcedconcrete beam

150 mm min.

Sand/cementscreed

BlockPouredconcrete

DPC

Figure 6.06 Block and beam floor constructionHeinemannNVQ2 Plumbing9pt Zurich BT�g05646/07/05

150 mm50 mm100 mm

600 x 3000 mm

50 mm screed

1 metre

150 mm min.

100 mm concreteslab

DPM50 mm insulationDPM

150 mm hardcore

Weak concrete incavity below groundlevel

Mass concrete strip

DPC

Weephole

Figure 6.07 Solid floor construction


precast concrete padstone all centre lines convergeon common points

rivet or bolt connections

8 mm thick gusset plate8 mmthick gusset plate

8 mm thickmild steel gusset plate

8 mm thickgussetplate

102 � 89 � 9.5 angle purlintrusses spacedat 3.000 centres

89 � 76 � 7.8 angle rafter

51 � 51 � 6.3 angle struts

64 � 51 � 6.2 angle tie

64 � 51 � 6.2 angle tie

64 � 51 � 9.5 fixing cleatsto both sides of gusset

alternative ~ 200 � 75 s/wpurlin screwed to152 � 102 � 9.5 angle cleat

152 � 76 � 9.5 angle cleat

Figure 6.08 Example of a steel truss roof

138



top flange

hexagonal voids

web

butt weld

bottomflange

Figure 6.09 Example of a castellated beam roof


UB spanningmember or beam

Welded gussetto apex

UC supportingmember

or columnFloorlevel

RC foundation

Purlincleat

Purlincleat

Column

Welded haunchgusset out ofUB section

Fixing platewelded to beamand boltedto column

Welded apexgusset plateout of UB section

Sheetingrail cleat

Web plates weldedto both sides

Ridge plates weldedto spanning membersand bolted togetheron site

Welded webplates toboth sides

Anglepurlin

Typical steel portal frame profile

Alternative apex details

Alternative knee joint details

UB spanningmember

Welded gussetto haunch or knee

Figure 6.10 Example of a steel portal roof

Did you know?

It is not uncommon to come across flat roofs that are not exactly flat but have a very slight slope, but the pitched roof is generally preferred

139


Construction materialsTypical construction materials for traditional buildings are:

• brick, concrete block or lightweight insulating block for walls

• timber for floor boards, stud work, roof beams, joists and rafters

• tile and slate for roofs

• plaster, plaster board and, in more recent years, PVC for window frames, gutters and drainage.


Punctured holes

Galvanisedsteel plate

Truss plate

Weatherboardso�t

Fascia

Trussed rafter

Alternativetruss plate

Spikes pressedout from plate


Rafter

Purlin

Ridge

Joist

Joist

Rafter

Fascia

Soffitboarding

Strap

Wallplate

Figure 6.11 Examples of timber roof construction

140


Modern industrial/commercial building construction The design of modern industrial/commercial buildings is based on a totally different concept from traditional methods. The underlying idea of the modern industrial unit is to produce a building that can be modified quickly and cheaply as the building tenancy changes. The flexibility to alter the internal features is now built into the design. It may be a low rise building, for example a retail store, or a multi-floor high rise building like an office block.

You may have noticed that some new buildings look like they are made totally from glass. However, the external glass and metal (and sometimes brickwork) of the building is there to make the building look nice and keep out the elements. It does not hold up the roof. The core of the building consists of a steel or reinforced concrete frame made up of beams, sub-beams and columns, with everything else, floors, walls, roofing as well as services, attached to the frame. Floors and stairs tend to be made of concrete to take the load of the furniture and people, and to help isolate each level in the event of a fire in the building.


Upstand beamas parapet

Main beams tocolumns tocentre accesscorridor

Floor slab spansbetween mainbeams and actsas a tie to frame

roof and floor spanbetween main beams

Main beamsspan along length ofbuilding

Columns

Figure 6.12 Modern building framework

Typical framed building materials would be reinforced concrete, steelwork columns and beams, glass, aluminium, brickwork, concrete block work and metal sheet cladding.

141


Mechanical services in buildings It is a more difficult job to install heating and RAC components in older traditional buildings. These buildings do not cater for the easy inclusion of mechanical engineering services like pipes and ductwork. They were originally built without the need for heating and air conditioning, as we know it today; and, therefore, services have been installed as an after thought, usually as the building has been modernised. The pipes, ductwork and plant generally utilise spaces formed naturally in the building structure, like roof spaces, spaces above a ceiling, or basements and cellars.

The exceptions to this can be where floor ducts or wall ducts and shafts were introduced in the original design. A lot of older schools and hospitals are like this. The basement area is usually where the central plant is housed and pipework and cables rising in vertical shafts supply all the floors above. You may have noticed rectangular panels in the floor at your school. These are the access points to floor ducts and are there for maintenance access.

The inclusion of mechanical services in modern buildings is now seen as essential to the whole design, and provision is included for all items that service them: electrical, heating, air conditioning, waste water, together with central control systems (BMS – building management systems, see page 76) incorporating both building climate control and security. In some cases they are not concealed but left exposed as a feature of the building.

Services typically are contained in a central service core and radiate out to the outer perimeter of each floor. Piped services may start from plant rooms in a basement (known as up feed systems) or more typically at roof level (down feed systems). Ease of access for installation and servicing is part of the overall plan.

As walls are temporary partitions within the building, most heating and air conditioning equipment is suspended from the underside of the reinforced concrete floor above, concealed by a false ceiling. The ceilings also hang from the floor above and are removable to expose the cables, ductwork and pipes installed in the space between.


(a) Flexible services

(c) Recessed type

G. L.

Filling withplastic material

Frame

Removablepanel

Plaster PlasterAccess door with insulatingboard at rear

Flexiblepipe

Insulatingboard

Accesspanel

Pipes orcables

Floorfinish

Chase

Insulatingboard Tee or angle type support

(b) Floor duct

(d) Partially recessed for medium-sized pipes and cables

Figure 6.13 Sections through wall and floor ducts

142


Vertical shafts have access doors on each floor level.J6990HED Mechanical Eng BW PDFAW_089AW by HL Studios

Cable trayand conduit

Pipework securedto structural floor

Air conditioningduct

Structuralfloor

Steel angle cleatand hanger (lengthvaries to suitservice provision)

LuminaireTee supportframe

Composite panelor ceiling tile

Firestopping

Figure 6.14 Ceiling grid


Pipes

Built-out for large pipes and cables

Cables

Figure 6.15 Vertical service shafts

Open plan offices now have a special floor above the structural, reinforced concrete floor, with the small space between the two purposely there to accommodate services. The upper level of the two floors can be entirely formed of square sections, each of which can be lifted out for access. The concept was originally introduced for computer rooms but is now extended to general offices.


100 to600 mm

Base plate screwed or bondedto structural floor

Void for cabletrays, ventilationducts andpipework

600 � 600 mm floorpanel. 30–40 mmthickness

Adjustable leg

Lock nut

Countersunkscrews intosupport plate

Figure 6.16 Computer flooring

There are always variations!

143


Safe working methods in industrial/commercial buildings

Fixing to the frame of the buildingBeams or columns should not be cut into or welded to. Any fixing to them must clamp to the structure. Fixings into reinforced concrete should use good quality anchors made for the job and avoid the structural reinforcement where possible.

Safe methods of working around open shafts and floor ducts Access to services contained in floor and vertical shafts are readily available but it is important that some safety procedures be adopted when open access is being gained. If the site is occupied there should be a ‘permit to work’ system in place, so that the management of the building can control where and how people work.

It is normal to have to obtain a permit before starting work and the permit will stipulate the safety precautions required for the task. These precautions could include:

• barriers around the work area with signs advising of the hazards

• a check on air quality if the shaft or duct is sealed

• ensuring that adequate lighting is available

• in some cases confined space procedure may be required.

Safe access to ceiling spacesFalse ceiling panels or tiles are easily removed, in most instances, by simply lifting and twisting to one side and then dropping out through the hole in the grid. However, the removal of false ceiling tiles for access to building services requires some safe procedures to be observed.

• The area should be cordoned off to warn others that work is in progress and notices posted to that effect.

• Access equipment used should be suitable for the purpose and carry a current safety certificate.

• Ceiling panels should be removed carefully with clean hands and placed where they will not be damaged.

• The area above the ceiling should be checked for dust and foreign objects left behind from previous operations.

• Adequate lighting should be arranged.

• Trailing leads should be not present as a trip hazard to others.

144


Holes in structuresIt is common practice, when cutting holes for services in building structures, to use a builder to cut the holes and make good. The role of the engineer is to indicate accurately where the holes are to be cut or formed by drilling. If there is no builder on site, for instance on a domestic property where the installer may be alone, then the engineer would be responsible for the task.

Holes in brickwork are usually formed using a hammer and chisel. They should be cut carefully to conform to the structural features of the building, for instance cutting brickwork in sympathy with the bond of the bricks. Making good should also follow the original pattern of the bond and be of similar finish. Holes in reinforced concrete structures are normally cast into the structure as the construction proceeds, or core drilled.

It is normal for the MES engineer on site to liaise with the builder to ensure that mistakes are kept to a minimum.

MES materialsThere is wide range of materials used in the MES sector, including the following:

• Lowcarbonsteel(LCS). Steel is primarily an alloy of iron and carbon, with the amount of carbon determining its properties. Of the range of steels available, LCS is next to pure iron in being soft and easy to shape and form. It is a basic material for pipes, fittings, pipe supports, sections, sheet and plate.

• Stainlesssteel is a corrosion resistant steel. It is also an alloy of iron and carbon, but with the addition of other metals, like chromium and nickel, to provide the corrosion resistance. In its low carbon form it is used for the manufacture of pipes, fittings and components like sink units and work tops.

• Galvanisedsteel is a product that is made from LCS and coated with zinc, which is strongly resistant to oxidation. The galvanising process involves cleaning the manufactured object in acid and then hot dipping it in molten zinc, which adheres to the surface.

• Copper is a base metal, which is used in the formation of pipes and fittings. It can also be obtained as a sheet material for weather cladding on buildings. Alloys of copper are used extensively for the production of valves and other fittings. The principal copper alloys are brass, gunmetal and bronze.

• Aluminium is a base metal used in the MES sector as a material for producing cast components. It can also be obtained as extrusions and sheet materials. It can be alloyed with magnesium and silicon to improve its mechanical properties.

Definition

Extrusion is a process for forming pipes, which involves forcing the material out through a circular slot under high pressure

145


• Lead is a very soft material and corrosion resistant. It has been used extensively on roofs, guttering, and even internally for pipes, for many centuries. Its use is fast reducing but MES engineers will still come across it. It is toxic, and special skills and precautions are needed to work with it.

Identification, characteristics and some uses of common MES materials are covered below.

Low carbon steel pipe and fittingsLCS pipe used in this industry is made to BS 1387. It is supplied either as black or galvanised pipe (see above). A standard length is approximately 6.4 metres and can be obtained with screw and socket ends, or just plain.

There are two main grades of LCS pipe: medium, traditionally indicated by a blue band painted around the pipe near the ends, and heavy, traditionally indicated by a red band painted around the pipe near the ends. LCS pipe is now being supplied with a red oxide paint coating; with the grade of pipe printed in black along its length.

During manufacture, the outside diameter of the pipe is kept fairly constant and any difference taken up in the bore of the pipe. This produces a bore diameter that can fluctuate in size. Hence the sizes of pipe are referred to as nominal or, more correctly, nominal bore – nb for short.

The range of LCS pipe sizes, with nominal bore in millimetres, are:

6, 8, 10, 15, 20, 25, 32, 40, 50, 65, 80, 100, 125, 150.

Fittings for LCS pipe are manufactured from either steel, malleable iron or cast iron. Steel fittings include flanges and tubulars (fittings made from pieces of pipe). Malleable iron is a heat-treated cast iron and is the typical material for LCS pipe fittings. Cast iron fittings are used extensively for fire control systems and large valves.

Copper tube and fittingsCopper tube is produced by extrusion, so the product is of uniform size throughout with no seam. It is supplied by grade or ‘table’. Tube size relates to the outside diameter of the tube.

Copper tube for the refrigeration and air conditioning industries is supplied in either soft drawn coils or annealed half hard rigid lengths, supplied with end caps to prevent ingress of moisture and foreign matter.

Refrigeration and air conditioning pipework requires specific graded or pressure rated copper tube suitable to the types of refrigerant in use.

J6990 HED Mechanical Eng BW PDF AW_092_J6990 AW by HL Studios

Figure 6.17 LCS pipe fittings

Remember

Copper pipe fittings intended for plumbing and heating systems are not compatible with RAC systems

146


Refrigeration copper tube is manufactured to British and European Standards BSEN 1057 (BS2871 Part 2) and EN 12449, with EN378 being the standard for safety and environmental aspects of design and installation of refrigeration systems.

Tables of copper tube suitable for water / plumbing applications are:

• TableW. Produced for small bore heating installations, gas and oil installations. It is supplied fully annealed, and in coils. It may be plastic coated for installing in concrete floors. Standard sizes are 6 mm, 8 mm, 10 mm and 12 mm diameter.

• TableX. Produced for all piped services in buildings. Supplied in ‘half hard’ condition and in rigid lengths of 3 metres or 6 metres. Standard sizes are 15 mm, 22 mm, 28 mm, 35 mm, 40 mm and 54 mm diameter.

• TableY. Produced for underground services. It is available fully annealed and in 25 metre coils. It is the thickest copper tube available and can be obtained plastic coated, yellow for gas services and blue for cold water supplies. Standard sizes are 15 mm and 22 mm.

• TableZ. Available in rigid lengths, ‘fully hard’ condition and with a very thin wall. Sizes range from 15 mm to 54 mm.

Fittings for copper tube are produced from copper or copper alloys. They are made to be compatible with heat jointing or mechanical jointing techniques.

Definition

When referring to the condition of copper products, the terms ‘half hard’, and ‘full hard’ relate to the final condition of the material. Copper is hardened by cold working and tempered to increase its toughness by controlled heating and cooling. Annealing also uses controlled heating and cooling to soften it, so that it is easy to work.

Figure 6.18 Copper fittings

Plastic materialsThe types of plastic material used for piping are extensive, and new products are being developed all the time. The common plastic products in use for industrial/commercial installations are:

• Unplasticisedpolyvinylchloride(uPVC). Maximum operating temperature is 60°C. It is light, easy to handle and install, and with a high resistance to chemicals and corrosion. It is used for process pipework, mains water, chlorinated water, and other liquids that normally would be incompatible for use with metals. (It is also sold as UPVC or PVCU.)

147


• Highimpactpolyvinylchloride(HIPVC). This is similar to uPVC but able to stand more external wear and abrasion.

• Acrylonitrilebutadienestyrene(ABS). This has a higher operating temperature to 80°C. It is suitable for all waste water systems and most corrosive chemicals.

• Polypropylene. This has an operating range up to 100°C and is very resistant to attack by acids. Used extensively in laboratory waste systems.

• Lowandhighdensitypolythene. This has a lower operating temperature range than polypropylene but with a higher resistance to attack by acids. Again, it will be found in laboratory waste installations.

The standard range of fittings are available, i.e. tees, elbows, unions, flanges etc. The materials that fittings and pipes are made from must be compatible with each other to ensure a good leak free system.

MES sheet materials Sheet materials found in the sector are related to those required for the production of ducting, and cover panels for boilers etc. The common sheet material used is galvanised low carbon steel.

Thermal insulationIn the pursuit of enhanced thermal efficiency in buildings, all services are either insulated to keep heat in (as in heating systems) or to keep heat out (as in cooling systems). Sections of insulating material are either provided as sheet that is intended to be cut and formed to shape or preformed to fit around cylindrical items, like cylinders or pipework.

The range of common insulation materials are:

• Foamrubber. Produced for the RAC industry as an insulation for cold surfaces.

• Cork. A natural product that is used less and less but may be found insulating chilled water plant and pipework.

• Glassfibre. This tends to be on the way out for insulating building services but is still used extensively for building structure insulation.

• Polyurethanefoam. It is now very common as an insulating medium, especially around pipes.

When handling insulation materials a risk assessment should be conducted to ascertain the degree of hazards involved.

Although classified as inert, glass fibre and foam should be considered as irritants, therefore an operative having to work with these materials should wear full personal protective equipment, i.e. overalls, head covering, face mask and gloves. Other people in the area should also be advised of the work being carried out.

148


Asbestos may be present in older buildings, in the form of insulation around pipework and steelwork, or as asbestos cement products, such as flues and building panels. Asbestos is responsible for many deaths each year due to uncontrolled exposure in the past. Asbestos cement products contain only a small amount of asbestos but still need careful handling when shaping and cutting. Wetting the surface and using only hand tools should suppress any dust created from cutting operations. Redundant materials should only be disposed of via licensed centres.

Asbestos insulation is very hazardous and, if found on site, it may require the resources of a specialist contractor to remove and make safe. If white or grey flake-like powder is found on a job and is suspected to be asbestos, advice should be immediately sought from the site manager. Samples will be taken and analysed. Under a management of asbestos policy all that may be required is to seal the location and leave it undisturbed. An engineer always has the responsibility to be sensible when working around old heating and ventilating plant rooms and not to disturb old insulation. Ensure that any work carried out is completed within the site policy requirements.

1. State the purpose of a wall in a traditional building.

2. List three roof covering materials.

3. Explain what a floor duct is used for.

4. Explain what is meant by the term ‘low carbon steel’.

5. List three copper alloys.

6. List the two grades of LCS pipe.

7. Explain where table X copper tube would be used in a building.

8. Explain what would need to done if white flaky powder covering pipework is discovered in a plant room.

9. Describe what Personal Protective Equipment may be required when handling insulation materials.

Knowledge check

Chapter 1 The MES Sector organisation, basic safety and communications

1. InrelationtoabuildingcontractaBuildingMerchantisresponsiblefor:a) orderingmaterialsontimeb)controllingmaterialcostsc) supplyingmaterialsd)selectingmaterials.

2. Ifanoperatorhasagrievanceheshouldfirstraiseitwiththe:a) clerkofworksb)siteagentc) immediatesupervisord)generalforeman.

3. Completethefollowingsentence.Ariskassessmentis:a) adocumentcompletedafteranaccidentb)adocumentcompletedbytheHealthand

SafetyExecutivec) ameansofidentifyinghazardsandwhat

mightgowrongd) thesiteengineersoffice.

4. WhatisthemostimportantitemofPersonalProtectiveEquipment(PPE)whenworkingonornearahighway?a) safetybootsb)highvisibilityvestc) hardhatd)waterproofclothing.

5. Afirewhichhasstartedduetoanelectricalfaultandstillinvolveselectricalapplianceswouldbestbecontrolledbytheuseof:a) waterb)anasbestosblanketc) sandd)aCO

2extinguisher

Chapter 2 Identify the physical forces that have an impact on the MES sector

1. Boyle’slawrelatesto:a) pressureandtemperatureb)volumeandmassc) pressureandvolumed)massandtemperature

2. TheamountofheatrequiredtoraiseonekilogrammeofasubstancethroughonedegreeCelsiusisits:a) specificheatcapacityb) totalheatcapacityc) latentheatcapacityd)sensibleheatcapacity.

3. Acubicmetreofwateratmaximumdensityhasamassof:a) 100kgb)500kgc) 900kgd)1000kg

Multiple choice questions

149

150

Chapter 3 Interpret drawing, specifications and data and describe the use of IT in the sector

1. Whatisthecolourofpropanegascylinders?a) Blackb)Maroonc) Redd)Blue

2. Whatisthecolourofanacetylenecylinderusedforoxyacetylenewelding?a) Orangeb)Blackc) Greend)Maroon

3. Aspecificationforaprojectcontainsinformationonthe:a) materialsandworkmanshipb) termsofthecontractc) labourcostofsiteemployeesd)stagesoftheworkcompleted.

4. A5mmlengthshownonadrawingtorepresentatruelengthof1misdrawntoascaleof:a) 1:50b)1:100c) 1:200d)1:500

5. Thedrawingusedtoshowtherelationshipofaproposedbuildingsitetoexistingroads,buildingsandspacesis:a) adetaileddrawingb)anassemblydrawingc) asitepland)ablockplan.

Chapter 4 Tools and the work processes used in the MES sector

1. Whoshouldoperateaplantandequipment?a) Onlypeopleover18yearsold.b)Experienceemployers.c) Trainedandauthorisedemployees.d)Employeeholdingafulldrivinglicence.

2. Thedeviceusedtostepthevoltageuptogridvaluesisa:a) transformerb) turbinec) alternatord)generator.

3. Thetoolusedtomarkthepositionofaholeinmetalpriortodrillingiscalleda:a) centrepunchb)nailpunchc) holepunchd)profilepunch.

4. Aburrinsideapipeshouldberemovedby:a) ahalfroundfileb)aflatfilec) ahacksawbladed)acoldchisel

5. Whyshouldpaintedladdersnotbeused?a) Becauseitcanhidedefects.b)Paintingmakeswoodshrink.c) Paintingmakestherungsslipperyand

unsafe.d)Paintingmakesthewoodbrittle.

6. Acompressionfittingwhichrequirestheendofthecopperpipetobeworkedisreferredtoasa:a) non-manipulativefittingb)primofitfittingc) manipulativefittingd)victaulicfitting.

Chapter 5 Calculate and quantify from drawings and set and mark out

1. Onelitreofwaterhasamassofa) 6.25kgb)1kgc) 10kgd)14.7kg

2. Theformulaforcalculatingtheareaofacircleis:a) πr2

b)πrc) 2πrd)πr3


Multiple choice questions

3. Howmanylitresofwatercanbestoredinatankmeasuring3m×2m×1mhigh?a) 5000litresb)6000litresc) 1600litresd)1200litres

4. Ifacylinderhasadiameterof500mm,whatwillbetheminimumlengthofstraprequiredtogoroundthecylinder?a) 1.67mb)1.57mc) 1500mmd)1600mm


1. Whenworkingonacentralheatingsystem,youcomeacrosssomepipeworkinsulatedwithahardwhitepowderymaterialthatcouldbeasbestos.Whatshouldyoudo?a) Whilewearingafacemask,removethe

materialanddisposeofitsafely.b)Removethematerial,puttingitbackon

thepipeworkafterfinishingthejob.c) Stopworkimmediatelyandtellyour

supervisoraboutthematerial.d)Dampthematerialdownwithwaterand

removeitbeforecarryingoutthework.

2. Whenworkingwithfibreglassroofinsulation,whichofthefollowingitemsofpersonalprotective(PPE)shouldyouwear?a) Gloves,facemaskandeyeprotection.b)Boots,eyeprotectionandeardefenders.c) Eardefenders,facemaskandboots.d)Barriercream,eyeprotectionandface

mask.

3. Topreventtheplastercracking,whenacopperpipepassesthroughawallitshouldhavea:a) flexiblejointb)metalsleevec) plasterfilledjointd)cementmortarjoint.

4. Whereawaterservicepipeentersthebuildingitshouldbe:a) takenupabovethedampproofcourse

beforeenteringthebuildingb)fixedinthecavitywallc) sleevedthroughtheoutsidewalland

broughtuponaninsidewalld) takenbelowthefoundationse) takenthroughthewallandbroughtup

ontheinsidefaceofanexternalwall.

Answers

Chapter 11. C2. C3. C4. B5. D

Chapter 21. C2. A3. D

Chapter 31. C2. D3. A4. C5. D

Chapter 41. C2. A3. A4. B5. A6. B

Chapter 51. B2. A3. B4. B

Chapter 61. C2. A3. B4. C

151

152

Th

e fo

llow

ing

tab

le d

etai

ls h

ow th

e H

vacr

trai

nin

g m

ater

ials

res

ou

rce

(jo

int i

nit

iati

ve b

y H

arco

urt

& S

um

mit

Skil

ls)

mat

ches

to th

e u

nit

s re

qu

irem

ents

of t

he

core

un

its

of t

he

H&

V a

nd

RA

C T

ech

nic

al C

erti

fica

te.

Tech

nic

al C

erti

fica

te C

ore

Un

its

Ch

apte

r 1C

hap

ter 2

Ch

apte

r 3C

hap

ter 4

Ch

apte

r 5C

hap

ter 6

Stud

ent b

ook

chap

ters

The

MES

sec

tor,

the

mai

n b

odie

s &

or

gani

satio

ns w

ithin

the

sect

or &

the

bas

ic

safe

ty &

com

mun

icat

ion

issu

es th

at a

pp

ly

Page

1

Uni

t 101

.1

Iden

tify

the

phy

sica

l for

ces

that

hav

e an

im

pac

t on

the

MES

sec

tor

Page

35

Uni

t 101

.2

Inte

rpre

t dra

win

gs, s

pec

ifica

tions

, dat

a an

d de

scrib

e th

e us

e of

IT in

the

sect

orPa

ge 6

5 U

nit 1

01.3

Tool

s an

d th

e w

ork

pro

cess

es u

sed

in th

e M

ES s

ecto

rPa

ge 7

9 U

nit 1

01.4

Cal

cula

te &

qua

ntify

from

dra

win

gs a

nd

mar

k an

d se

t out

Page

115

U

nit 1

01.5

Und

erst

and

bui

ldin

g co

nstr

uctio

n m

etho

ds

and

the

mat

eria

ls u

sed

in th

e M

ES s

ecto

rPa

ge 1

33

Uni

t 101

.6


153

Mapping documents

Th

e fo

llow

ing

tab

le d

etai

ls h

ow th

e H

vacr

trai

nin

g m

ater

ials

res

ou

rce

(jo

int i

nit

iati

ve b

y H

arco

urt

& S

um

mit

Skil

ls)

mat

ches

to th

e co

mm

on

co

re

un

its

req

uir

emen

ts o

f th

e H

eati

ng

& V

enti

lati

ng

and

Ref

rige

rati

on

& A

ir C

on

dit

ion

ing

S/N

VQ

Lev

el 2

.

Hea

tin

g &

Ven

tila

tin

g a

nd

Ref

rig

erat

ion

& A

ir C

on

dit

ion

ing

S/N

VQ

Co

mm

on

Co

re U

nit

s/el

emen

ts

Uni

t 1

Mai

ntai

n th

e sa

fe w

orki

ng

envi

ronm

ent f

or H

vacr

wor

k ac

tiviti

es

Uni

t 2

Mai

ntai

n eff

ectiv

e w

orki

ng

rela

tions

hip

s

Uni

t 3

Con

trib

ute

to th

e im

pro

vem

ent o

f bus

ines

s p

rodu

cts

&

serv

ices

for H

vacr

act

iviti

es

Elem

ent 1

.1El

emen

t 1.2

Elem

ent 2

.1El

emen

t 3.1

Elem

ent 3

.2El

emen

t 3.3

Stud

ent b

ook

chap

ters

The

MES

sec

tor,

the

mai

n b

odie

s &

org

anis

atio

ns w

ithin

th

e se

ctor

& th

e b

asic

saf

ety

&

com

mun

icat

ion

issu

es th

at a

pp

ly

Page

s 8-

11, 1

2-34

Page

s 11

-18,

20

-29,

34

Page

s 2-

10, 1

4, 1

6,

18, 2

8-34

Page

s 1-

5, 1

3-16

, 18

, 27-

34Pa

ges

4-5,

9-1

1,

12, 1

8, 2

6-34

Page

s 10

, 16-

19

Iden

tify

the

phys

ical

forc

es th

at

have

an

impa

ct o

n th

e M

ES s

ecto

rPa

ges

51, 5

9, 6

0Pa

ges

43, 5

9, 6

0N

/APa

ges

36-3

7,

40-4

1, 4

3-45

Page

s 58

-61

Page

s 46

, 59-

60

Inte

rpre

t dra

win

gs,

spec

ifica

tions

, dat

a an

d de

scrib

e th

e us

e of

IT in

the

sect

orPa

ge 7

1Pa

ges

68, 7

1-73

Page

s 66

, 68-

78Pa

ges

66, 6

8-78

Page

s 74

-78

Page

76

Tool

s an

d th

e w

ork

pro

cess

es

used

in th

e M

ES s

ecto

rPa

ges

90-9

2, 1

01

Page

s 80

, 82,

86,

88

, 90-

92, 1

01,

105-

106,

108

, 11

2-11

4

Page

s 11

5-11

6Pa

ges

116,

12

0-12

2Pa

ges

91-9

2Pa

ges

88-9

2

Cal

cula

te &

qua

ntify

from

dr

awin

gs a

nd m

ark

and

set o

utN

/AN

/APa

ge 1

15-1

16Pa

ges

116,

12

0-12

2Pa

ges

120-

121

Page

126

Und

erst

and

bui

ldin

g co

nstr

uctio

n m

etho

ds a

nd th

e m

ater

ials

use

d in

the

MES

sec

tor

Page

s 14

3, 1

47Pa

ges

143,

14

7-14

8Pa

ges

144,

14

7-14

8Pa

ges

141,

144

Page

s 14

1, 1

44Pa

ges

133-

148

Air Conditioning and Refrigeration Industry 5

engineers 80

alloys 89, 95

anaerobic adhesive 92

AMICUS 4

beam folder 100

bending 98-106, 127

hand bending 103

hot bending 101-102

pipe bending 127

safety 101

sheet materials 97

spring back 99

blades 109-110

bolts 81-82

boom lift see working at height

buildings

construction 134-135, 140

types 134

building management systems 76

calculations

area 118

quantity 118-119

volume 118

ceiling construction 136

chemistry 53

combustion 59

corrosion 60-61

metals 57-59

reactions 54, 56

symbols 54

chisel 113

chop saw 113-114

clamp folder see beam folder

communication 30-33

face-to-face 30

letters/memos 33

phone 30

text message 31

time sheets 33

written 31

Construction Design and Management Regulations (CDM) 13

construction materials 139

Control of Substances Hazardous to Health (COSHH) 8, 11

copper tube 144, 145-146

bending 103-105

marking out 130-131

die 86

drawings 66

exploded views 68

interpreting 115-117

MES 69

scaled views 67

sectional view 67

symbols and abbreviations 70

three dimensional view 67-68

title block 66

drilling 96-97

core drill 97

shanks 96-97

twist drill 96

ductwork 83

electrical cabling

identification 73

electricity 62-64

circuits 63-64

current 63

elements 55

energy 38

engineers

role 80, 116

excavations 23

files 107-109

fire safety 16-19

causes of fire 16

fire extinguishers 18, 19

Index

154

155

Index

fire plans 12

fire prevention 17-18

fire triangle 17

first aid 12, 28

first aid for electric shock 28

fixing devices 92-96

heavy 94

light 93-94

screw 94-95

flange joint 81

floor construction 136-137

folding 97, 98

folding bar 99

force 38, 40, 44

action and reaction 41

centre of gravity 42

equilibrium 42-43

fusion welding 90

gas cylinders

identification 72

hacksaw 110

hand bender 104

hand shears 111

Health and safety 8-12

electrical safety 26-28

health and safety plan 13

heating 90

legal requirements 8

legislation 8

prevention of accidents 11

safety rules 10

soldering 89

tool care 88

Health and Safety at Work Act (HASAWA) 9

heat 48-53, 88-91

capacity 49

density 50

expansion and contraction 52-53

heat values 49

in building 143

jointing 88-91

properties 48

scales 48-49

transfer 51-52

Heating and Ventilating Contractor Association (HVCA) 4

heating and ventilation (H&V) 2

engineers 80

hot work permits 90-91

hydraulic press bender 105-106

marking out 129-130

information technology (IT) 74-77

building management system 76

disadvantages 77-78

office based 74

on site 75

isolation 11

jointing 80-91

adhesive 91-92

crimps 87

electrofusion 90

heat 88-91

mechanical methods 81-88

Ladders see working at height

legislation

access online 75

and specifications 71

health and safety 8

levers 43-44

Lifting and carrying 13

manual handling 24-25

guide weights 26

Manual Handling Operations Regulations 8, 24

marking out 119-131

accuracy 120

and building structure holes 126

and drilling 125

and pipework 126

bends 127-128

errors 121-122

pipe offset 128-129

progressive errors 120-121

techniques 122-124

tools 119

mass 38, 50-51

mechanical advantage 39

MES sector

and building 141-142

drawings 69

joining 2-3

materials 144-148

principle organisations 4-5

qualified engineers see engineers

service coding 71-72

trades 2

mobile scaffold tower see working at height

moment theory 40-41

National Vocational Qualifications (NVQs) 2-3

oils 55

personal presentation 29

Personal Protective Equipment (PPE) 10, 16

156

safety boots 16

safety gloves 16

safety goggles 15

safety helmets 14, 16

pipe cutting 112-113

pipe joints 83-92

compression 86-87

threaded 84-86

pipe offset 128-129

pipelines

identification 72

plastics 55-56, 146-147

plugs 93

power (measurement) 39

powered jigsaw 111

pressure 45-48

atmospheric pressure 47

gas pressure 47, 50

hydrostatic pressure 46

measurement 47-48

project management 5

project roles 6-7

pulley system 44-45

radiation 51-52

Refridgeration and air conditioning (RAC) 2

engineers 80

repairs 92

reports 31

service/maintenance 31, 32

technical 31

residual current device (RCD) 27

riveted joints 83

roll bender 100

roofing 137-139

safety signs 14

sawing sheet 109

scale 67, 117

scissor lift see working at height

screws 93

fixings 94-95

types 95

seaming 83

service engineers 80

SI units 36-37

soldering 88

brazing 89

safety 90, 91

silver soldering 89

soft soldering 88-89

solvent weld 91-92

spanners 81, 82

specifications 71

stand bender 104

states of matter 50, 53

steel pipe 144-145

steel pipe bending 105

hot bending 106

marking out 129-130

stock 86

SummitSkills 5

toggles

expansion 93

gravity 93

spring 93

velocity 40

wall construction 135-136

water 54-55

weight (measurement) 38

work (measurement) 38

working at height 12, 20-22

boom lift 22

ladders 20-21

mobile scaffold tower 21-22

scissor lift 22

wrenches

offset hex 87

pipe 84

socket 81

spud 87

stillson 84

torque 81


Documents

Heating & Ventilation, Air Conditioning & Refrigeration: Chapter 6