Introduction to HVACSystems (General).ppt

8/17/2019 Introduction to HVACSystems (General).ppt

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Introduction to HVAC Systems


2/94

Chapter one

HVAC Systems – An Exploded View



3/94

Comfort Requirements

Temperature

Humidity

Air movement Fresh air

Clean air

Noise levels Lihtin

Furniture and !or" surfaces


4/94

The Five System Loops

AirsideAirside

Chilled !ater Chilled !ater

RefrierationRefrieration

Heat re#ectionHeat re#ection

ControlsControls


5/94

Airside Loop

supply airsupply air

sensiblesensibleheatheat

moisturemoisture(latent heat)(latent heat)

return airreturn air

conditionedconditionedspacespace


6/94

Coolin Load Components

roofroof

lightslights

equipmentequipment

floorfloor

exteriorexterior wall wall

glassglasssolarsolar

glassglassconductionconduction

infiltrationinfiltrationpeoplepeople

partitionpartition wall wall


7/94

35°C35°C(95°F(95°F))

Supply Fan and Filter

supplysupplyfanfan

conditionedconditionedspacespace

RARA

OAOA

EAEA

239°!239°!("5°F)("5°F)

2#"°!2#"°!

($%°F)($%°F)

SASA

MAMAfilterfilter


8/94

Coolin Coil

headerheader

tubestubes

finsfins

RARA

OAOA

EAEA

SASA

MA

coolingcoolingcoilcoil

&2$°!&2$°!(55°F)(55°F)

95°F95°F(35°!)(35°!)

2#"°!2#"°!

($%°F)($%°F)

239°!239°!("5°F)("5°F)


9/94

Chilled$%ater Coolin Coil

drain pandrain pan

warm' warm'humid airhumid air

cool'cool'dry airdry air

condensate drain linecondensate drain line


10/94

part$load operation

Constant$Volume System

#5°F#5°F(&$3°!)(&$3°!)

SASA

constant supply$air quantityvaria&le supply$air temperature

95°F95°F(35°!)(35°!)

RARA

OAOA

EAEA

"5°F"5°F(239°!)(239°!)

$%°F$%°F

(2#"°!)(2#"°!)

MAMAfilterfilter


11/94

95°F95°F(35°!)(35°!)

RARA

OAOA

EAEA

"5°F"5°F(239°!)(239°!)

$%°F$%°F

(2#"°!)(2#"°!)

MAMA

part$load operation Varia&le$Air$Volume 'VAV( System

terminalterminalunitunit

SASA

55°F55°F(&2$°!)(&2$°!)

varia&le supply$air quantityconstant supply$air temperature

airflowairflowmodulationmodulationde*icede*ice

terminal unitterminal unit


12/94

Fan$Coil )nit

cooling coilcooling coil

supply fansupply fan

return+air inletreturn+air inlet

supply+air outletsupply+air outlet

filterfilter


13/94

Central Air Handler


supplysupplyfanfan outdoor+airoutdoor+airdampersdampers

return+airreturn+airdampersdampers

supply+airsupply+airoutletoutlet

filtersfilters


14/94

Supply$Air *istri&ution System

terminalterminal

diffuserdiffuser

flexibleflexible

ductductsheet+metal supply ductsheet+metal supply duct

centralcentralair handlerair handler

outdoor+air inletoutdoor+air inlet

return+airreturn+airinletinlet


15/94

Ceilin +lenum Return

roofroof

plenumplenum return airreturn air

ceilingceiling

supply airsupply airdiffuserdiffuser


16/94

Chilled$%ater Loop

,2°F,2°F(5#°!)(5#°!)

5"°F5"°F

(&39°!)(&39°!)

55°F55°F(&2$°!)(&2$°!)


$%°F$%°F(2#"°!)(2#"°!)


17/94

,2°F,2°F(5#°!)(5#°!)

5"°F5"°F

(&39°!)(&39°!)

55°F55°F(&2$°!)(&2$°!)


$%°F$%°F(2#"°!)(2#"°!)

,vaporator

e*aporatore*aporator


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Shell$and$Tu&e ,vaporator

refrigerantrefrigerant*apor*apor

chilled+waterchilled+water

returnreturn

chilled+waterchilled+watersupplysupply

tubestubes

liquid and *aporliquid and *aporrefrigerantrefrigerant


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,2°F,2°F(5#°!)(5#°!)

5"°F5"°F

(&39°!)(&39°!)

55°F55°F(&2$°!)(&2$°!)


$%°F$%°F(2#"°!)(2#"°!)


+ump and Control Valve

controlcontrol*al*e*al*e

pumppump


20/94

T!o$%ay Versus Three$%ay Valves

coil with two+waycoil with two+waycontrol *al*econtrol *al*e

coil with three+waycoil with three+waycontrol *al*econtrol *al*e


21/94

Small Chilled$%ater System

pumppump cooling coilcooling coil


water chiller water chiller


22/94

Refrieration Loop

3$°F3$°F(33°!)(33°!)

5%°F5%°F

(&%°!)(&%°!)

,2°F,2°F(5#°!)(5#°!)

5"°F5"°F

(&39°!)(&39°!)

55°F55°F(&2$°!)(&2$°!)

$%°F$%°F(2#"°!)(2#"°!)



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Compressor

compressorcompressor

&2%°F&2%°F

(,$9°!)(,$9°!)

-eciprocating-eciprocating

.croll.croll

/elical+rotary/elical+rotary(screw)(screw)

!entrifugal!entrifugal3$°F3$°F(33°!)(33°!)

5%°F5%°F

(&%°!)(&%°!)

,2°F,2°F(5#°!)(5#°!)

5"°F5"°F

(&39°!)(&39°!)

55°F55°F(&2$°!)(&2$°!)

$%°F$%°F(2#"°!)(2#"°!)



24/94


&2%°F&2%°F

(,$9°!)(,$9°!)

3$°F3$°F(33°!)(33°!)

5%°F5%°F

(&%°!)(&%°!)

,2°F,2°F(5#°!)(5#°!)

5"°F5"°F

(&39°!)(&39°!)

55°F55°F(&2$°!)(&2$°!)

$%°F$%°F(2#"°!)(2#"°!)


Condenser

condensercondenser&&%°F&&%°F

(,33°!)(,33°!)


25/94

Types of Condensers

propeller fanpropeller fan

sumpsump pumppump

finned+tube coilfinned+tube coil

liquid refrigerantliquid refrigerant

refrigerant *aporrefrigerant *apor

air$cooled

!ater$cooled

evaporative

outdoor airoutdoor air

refrigerant *aporrefrigerant *apor

liquid refrigerantliquid refrigerant

tubestubes

fanfan

condensercondenser water water


26/94


&2%°F&2%°F

(,$9°!)(,$9°!)

3$°F3$°F(33°!)(33°!)

5%°F5%°F

(&%°!)(&%°!)

,2°F,2°F(5#°!)(5#°!)

5"°F5"°F

(&39°!)(&39°!)

55°F55°F(&2$°!)(&2$°!)

$%°F$%°F(2#"°!)(2#"°!)


condensercondenser&&%°F&&%°F

(,33°!)(,33°!)

,-pansion *evice

expansionexpansionde*icede*ice


27/94

Helical$Rotary %ater Chiller

condensercondenser



condensercondenser water water

chilledchilled

water water


28/94

Finned$Tu&e ,vaporator 'Coil(


liquidrefrigerantairflowairflow


29/94


cooling coilcooling coil(e*aporator)(e*aporator)


No Chilled$%ater Loop

air+cooledair+cooledcondensercondenser


30/94

+ac"aed Rooftop Air Conditioner


air+cooled condenserair+cooled condenser compressorscompressors


exhaust fanexhaust fan

propeller+typepropeller+typecondenser fanscondenser fans

filtersfilters


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Heat$Re#ection Loop

coolingcoolingtowertower

condensercondenser

&%%°F&%%°F

(3"$°!)(3"$°!)

$5°F$5°F(29,°!)(29,°!)

&2%°F&2%°F

(,$9°!)(,$9°!)

3$°F3$°F(33°!)(33°!)

5%°F5%°F

(&%°!)(&%°!)

,2°F,2°F(5#°!)(5#°!)

5"°F5"°F

(&39°!)(&39°!)

55°F55°F(&2$°!)(&2$°!)

$%°F$%°F(2#"°!)(2#"°!)

&&%°F&&%°F(,33°!)(,33°!)


32/94

Coolin To!er

sprayssprays

from condenserfrom condenserto condenserto condenser

sump

propeller fanpropeller fan

outdoor airoutdoor air

fillfill


33/94

coolingcoolingtowertower

condensercondenser

&%%°F&%%°F

(3"$°!)(3"$°!)

$5°F$5°F(29,°!)(29,°!)

&2%°F&2%°F

(,$9°!)(,$9°!)

3$°F3$°F(33°!)(33°!)

5%°F5%°F

(&%°!)(&%°!)

,2°F,2°F(5#°!)(5#°!)

5"°F5"°F

(&39°!)(&39°!)

55°F55°F(&2$°!)(&2$°!)

$%°F$%°F(2#"°!)(2#"°!)

&&%°F&&%°F(,33°!)(,33°!)

+ump and Control Valve


pumppump


34/94

%ater Chiller and Coolin To!er

water+cooled condenser water+cooled condenser

cooling towercooling tower

bypass pipebypass pipe


pumppump


35/94

+ac"aed Air$Cooled Chiller

air+cooledair+cooledcondensercondenser


e*aporatore*aporatorpropeller+typepropeller+typecondenser fanscondenser fans


36/94

+ac"aed Air$Cooled Chiller


e*aporatore*aporator air+cooledair+cooledcondensercondenser



37/94

Controls Loop

building automation systembuilding automation system

system+le*el controllersystem+le*el controller


38/94

Rooftop VAV System

system+le*elsystem+le*elcontrollercontroller

terminals terminalspac0aged rooftoppac0aged rooftopair conditionerair conditioner


39/94

Air$Cooled Chiller. Fan$Coil System


air+cooled chillerair+cooled chiller

fan+coil unitsfan+coil units

dedicated outdoor+air unitdedicated outdoor+air unit

hot+water boilerhot+water boiler pumpspumps



40/94

period two

Direct Expansion (DX) Verss

C!illed"#ater Systems


Air Conditionin Clinic T R/$TRC012$,NAir Conditionin Clinic T R/$TRC012$,N© American Standard Inc. 2004


41/94

*irect ,-pansion '*3(

airflowairflowexpansionexpansion*al*e*al*e



liquidliquidrefrigerantrefrigerant


42/94

Air$Cooled *3 System

outdooroutdoorairair

condenser coilscondenser coils

propellerpropellerfansfans




air+cooledair+cooled

condensercondenser


43/94

+ac"aed *3 Air Conditioner


air+cooled condenserair+cooled condenser compressorscompressors



propeller+typepropeller+typecondenser fanscondenser fans

filtersfilters


44/94

Split *3 System

cooling coil(e*aporator)

supply fan

air+cooled condenser

compressorsrefrigerant piping

Air Conditionin Clinic T R/$TRC012$,N© American Standard Inc. 2004


45/94

Chilled$%ater Loop




pumppump


46/94

+ac"aed %ater Chillers

air$cooled

!ater$cooled


47/94

Split Chilled$%ater System

air+cooled condensing unitair+cooled condensing unit

remotee*aporator

refrigerantrefrigerantpipingpiping


48/94

*3 versus chilled !ater

Factors Affectin the *ecision

Installed cost

,nery consumption

Space requirements

Free4e prevention

5uildin heiht. si4e.shape

System capacity

Centrali4ed maintenance

Sta&ility of control

Individual tenant &illin


49/94

Installed Cost

air$cooled.chilled$!ater system

air$cooled *3 system


50/94

,nery Consumption

Compressor(s)

Spply and ex!ast (or retrn) $ans

Condenser (or coolin% tower) $ans

&mps

DXc!illedwater


51/94

Space Requirements

indoor equipment room

rooftop installation


52/94

Free4e +revention

%

&%

2%

3%

,%

5%

#%

+5%(+,#)

+,%(+,%)

+3%(+3,)

+2%(+29)

+&%(+23)

%(+&$)

&%(+&2)

2%(+")

temperature' °F (°!)temperature' °F (°!)

e t h y

l e n e g l y c o l c o n c e

n t r a t i o n '

e t h y

l e n e g l y c o l c o n c e

n t r a t i o n '

1 b

y w e i g h t

1 b

y w e i g h t

"%

3%(+&)

free4e protection

&urst protection


53/94

5uildin Heiht. Si4e. Shape


54/94

System Capacity

%%(%)(%)

cooling capacity' tons (0)cooling capacity' tons (0)

2%%2%%("%%)("%%)

,'%%%,'%%%(&,'%%%)(&,'%%%)

,%%,%%(&',%%)(&',%%)

pac"aed !ater chillers

*3 equipment e q u i p m e n t t y p e

e q u i p m e n t

t y p e


55/94

Centrali4ed 6aintenance



56/94

Sta&ility of Control

setpointsetpoint

chilled!ater

*3


57/94

Individual Tenant 5illin



58/94

period three

Common HVAC System 'ypes




59/94

System Cateories

sinle 4onesinle 4one

constant volumeconstant volume

air *olume deli*ered by supply fanair *olume deli*ered by supply fan

3 o n e s s e r * e d b y s u p p l y f a n



varia&le volumevaria&le volume

multiple 4onemultiple 4one

constant volumeconstant volumemultiple 4onemultiple 4one



60/94

Sinle 7one. Constant Volume


RAEA

OA

supplysupplyfanfan

thermostatthermostat

SA

oneone


61/94

sinle$4one systems

Sinle Thermostat


62/94

sinle 4one. constant volume

+ac"aed Terminal Air Conditioner

filterfilter

front grillefront grille


wall slee*e wall slee*e

condenser fancondenser fan

supply fansupply fan air+cooledair+cooledcondensercondenser

cooling coilcooling coil

(e*aporator)(e*aporator)


63/94


+ac"aed *3 Rooftop System

pac0aged rooftoppac0aged rooftopair conditionerair conditioner

diffuserdiffuser

sheet+metalsheet+metalsupply ductsupply duct


64/94

sinle 4one. constant volume Split *3 System

refrigerant piping


cooling coil(e*aporator)

supply fan

air+cooled condenser

compressors


65/94


Chilled$%ater Terminal System

classroomclassroomunit *entilatorunit *entilator

air+cooledair+cooled water chiller water chiller

pumpspumps

hot+waterhot+waterboilerboiler


66/94

sinle 4one. constant volume Four$+ipe Versus T!o$+ipe System

Coils per terminal nit

#ater distri*tion pipin% sets set

Heatin% and coolin% eit!er or *ot! mtallysimltaneosly exclsi+e

'emperatre control direct direct

Hmidity control direct indirect(i$ !eatin% coildownstreamo$ coolin% coil)

,"pipe "pipe


67/94

*edicated 8utdoor$Air System

4 ducted to4 ducted toterminal unitsterminal units

4 ducted to4 ducted to

plenum nearplenum nearterminal unitsterminal units

4 ducted4 ducteddirectly todirectly tospacesspaces


68/94

Sinle 7one. Varia&le Volume


RAEA

OA

supplysupplyfanfan


SA

oneone

*ariable+speed*ariable+speeddri*edri*e


69/94

System Cateories


constant volumeconstant volume

air *olume deli*ered by supply fanair *olume deli*ered by supply fan


3 o n e s s e r * e d b y s u

p p l y f a n



multiple 4onemultiple 4one

constant volumeconstant volumemultiple 4onemultiple 4one



70/94

6ultiple 7ones. Constant Volume


RAEA

OA

supplysupplyfanfan

SA

oneone


oneone

reheat coilreheat coil


71/94

multiple 4ones. constant volume

6ulti4one Air Handler

multione air handlermultione air handler

RAEA

OA

SA

oneonethermostatthermostat

oneone


72/94


Chaneover95ypass System

constant+*olume supply fan'constant+*olume supply fan'*ariable+*olume airflow to spaces*ariable+*olume airflow to spaces

RAEA

OAsupplysupply

fanfan

SA

oneone


oneone

damperdamper

bypass damperbypass damper


73/94


Chaneover95ypass System

pac0aged rooftoppac0aged rooftopair conditionerair conditioner

diffuserdiffuser

modulatingmodulatingdamperdamper

bypassbypassdamperdamper



74/94

6ultiple 7ones. Varia&le Volume

RAEA

OAsupplysupply

fanfan

oneone


oneone

box box

SA



75/94

multiple 4ones. varia&le volume

VAV Terminal )nits

coolingcooling

with reheat with reheat

parallelparallelfan+poweredfan+powered

seriesseriesfan+poweredfan+powered

cooling onlycooling only


76/94


*3 Rooftop VAV System

pac0aged 6 rooftoppac0aged 6 rooftopair conditionerair conditioner


terminal' terminal'diffusersdiffusers

supplysupplyreturnreturn


77/94


Self$Contained *3 VAV System



diffuserdiffuser

terminal terminal

hot+water boiler'hot+water boiler'

pumpspumps

self+containedself+contained

6 air conditioner6 air conditioner


78/94


Central Chilled$%ater VAV System



terminal' terminal'diffusersdiffusers

hot+water boiler'hot+water boiler'

pumpspumps

water+cooled water+cooled

chillerchiller

air handlerair handler


79/94


T!o$Fan. *ual$*uct VAV System

EA

OA PA

cooling air handlercooling air handler

PARA

heating air handlerheating air handler

dual+ductdual+duct terminal terminalunitsunits


80/94


*ual$*uct VAV Terminal )nit

cool primary aircool primary air

warm primary air warm primary air

supply airsupply air


81/94

period four

-actors '!at A$$ect Selection o$

t!e HVAC System




82/94

+reference of 5uildin 8!ner

8!ner

.ccpies *ildin%

*eveloper

/eases to tenants

0ay sell *ildin% soona$ter constrction


83/94

Availa&le Construction 5udet

mechanicalmechanical

interiorinterior

electricalelectricalstructurestructure

exterior'exterior'roofroof

foundationfoundation

otherother


84/94

Si4e and Shape of 5uildin


85/94

Function of 5uildin

Comfort requirements

'emperatre

Hmidity

Air mo+ement

-res! air

Clean air

1oise le+els Num&er of tenants

After$hours usae


86/94

Architectural Limitations



87/94

Life$Cycle Cost

Installation

,nery 'operation(

6aintenance

Replacement


88/94

,ase of 8peration and 6aintenance


89/94

Time Availa&le for Construction



90/94

period five

2e+iew




91/94

Revie!:+eriod 8ne

building automation systembuilding automation system



92/94

Revie!:+eriod T!o

pac"aed *3rooftop air conditioner

pac"aedair$cooled !ater chiller


93/94

Revie!:+eriod Three

multiple$4one. centralchilled$!ater VAV system

sinle$4one. pac"aed

*3 rooftop system


94/94

Revie!:+eriod Four

+reference of &uildin o!ner

Availa&le construction &udet

Si4e and shape of &uildin

Function of &uildin 'comfort requirements(

Architectural limitations

Life$cycle cost

,ase of operation and maintenance

Time availa&le for construction

Documents

Introduction to HVACSystems (General).ppt