Chilled-Water VAV Systems - HVAC.Amickracing

More documents

Recommendations

Info

VAV terminal units ..................................................................... 183Zone temperature control ................................................... 183Ventilation control ............................................................... 184Space pressure control ....................................................... 187Safeties ............................................................................... 188Water chiller ............................................................................... 188Condensing pressure control ............................................. 188Hot-water boiler ......................................................................... 190Return water temperature control ...................................... 190System-Level Control .................................................................... 190Coordination during different operating modes ......................... 191Occupied mode .................................................................. 191Occupied standby mode .................................................... 192Unoccupied mode .............................................................. 193Morning warm-up (or cool-down) mode ............................. 194Scheduling ................................................................................. 196Chilled-water plant ..................................................................... 197Hot-water plant .......................................................................... 197System optimization .................................................................. 198Optimal start ....................................................................... 198Optimal stop ....................................................................... 199Unoccupied “economizing” ................................................ 199Fan-pressure optimization ................................................. 200Supply-air-temperature reset ............................................. 202Ventilation optimization ...................................................... 205Pump-pressure optimization .............................................. 208Chilled-water temperature reset ........................................ 208Hot-water temperature reset ............................................. 209Condenser-water temperature (chiller-tower) optimization . 210Coordination with other building systems .................................. 211Glossary .......................................................................................... 213References .................................................................................... 225Index ............................................................................................... 230vi Chilled-Water VAV Systems SYS-APM008-EN
Overview of aChilled-Water VAV SystemA typical chilled-water variable-air-volume (VAV) system consists of a VAV airhandlingunit that serves several individually controlled zones. Each zone hasa VAV terminal unit that varies the quantity of air delivered to maintain thedesired temperature in that zone.The primary components of a typical chilled-water VAV system (Figure 1)include:• VAV air-handling unit that contains a mixing box; filters; a chilled-watercooling coil; possibly a heating coil, gas-fired burner, or electric heater; avariable-volume supply fan; possibly a return or relief fan; and controls• VAV terminal unit with a temperature sensor for each independentlycontrolled zone• Supply ductwork and supply-air diffusers• Return-air grilles, ceiling plenum, and return ductwork• Water chiller(s) with associated water distribution pumps and heatrejection equipment (cooling towers for water-cooled chillers, condenserfans for air-cooled chillers)• Hot-water boiler(s), with associated water distribution pumps, or electricheat• System-level controlsFigure 1. Primary components of a chilled-water VAV systemVAVair-handlingunitsupply ductworksupply-air diffuserVAV terminal unitchilled-waterdistributionpumpswater chillersSYS-APM008-EN Chilled-Water VAV Systems 1
Page 3 and 4: Chilled-WaterVAV SystemsJohn Murphy
Page 5 and 6: ContentsPreface ...................
Page 10 and 11: Overview of a Chilled-Water VAV Sys
Page 20 and 21: Primary System Componentsunit are t
Page 22 and 23: Primary System ComponentsAvoiding f
Page 24 and 25: Primary System ComponentsFigure 10.
Page 28 and 29: Primary System Componentsweather, a
Page 32 and 33: Primary System Componentsair to a t
Page 34 and 35: Primary System Componentsbarometric
Page 36 and 37: Primary System ComponentsFigure 20
Page 38 and 39: Primary System ComponentsSupply fan
Page 40 and 41: Primary System ComponentsFan typesV
Page 42 and 43: Primary System ComponentsTo allow a
Page 44 and 45: Primary System ComponentsIn a draw-
Page 46 and 47: Primary System ComponentsSupply fan
Page 48 and 49: Primary System ComponentsThe modula
Page 50 and 51: Primary System ComponentsTable 8. A
Page 54 and 55: Primary System Componentssystem. So
Page 56 and 57: Primary System ComponentsPhotocatal
Page 58 and 59:
Primary System ComponentsPCO techno
Page 60 and 61:
Primary System Componentsand upstre
Page 62 and 63:
Primary System ComponentsThermal pe
Page 64 and 65:
Primary System ComponentsFigure 47.
Page 66 and 67:
Primary System ComponentsFan-powere
Page 68 and 69:
Primary System Componentspowered VA
Page 70 and 71:
Primary System Componentsinterfere
Page 72 and 73:
Primary System ComponentsIf the des
Page 74 and 75:
Primary System ComponentsTypically,
Page 76 and 77:
Primary System ComponentsInterior z
Page 78 and 79:
Primary System ComponentsInterior z
Page 80 and 81:
Primary System ComponentsEqual fric
Page 82 and 83:
Primary System Components• If nee
Page 84 and 85:
Primary System ComponentsIn additio
Page 86 and 87:
Page 88 and 89:
Primary System ComponentsAir-cooled
Page 90 and 91:
Primary System Componentstemperatur
Page 92 and 93:
Page 94 and 95:
Primary System ComponentsVariable-
Page 96 and 97:
Primary System ComponentsFreeze pre
Page 98 and 99:
Primary System Componentsrow coil i
Page 100 and 101:
Primary System ComponentsThermal st
Page 102 and 103:
Primary System Components(although
Page 104 and 105:
Page 106 and 107:
Primary System ComponentsA variable
Page 108 and 109:
System Design Issues and Challenges
Page 110 and 111:
Page 112 and 113:
Page 114 and 115:
Page 116 and 117:
Page 118 and 119:
Page 120 and 121:
Page 122 and 123:
Page 124 and 125:
Page 126 and 127:
Page 129 and 130:
Page 131 and 132:
Page 133 and 134:
Page 135 and 136:
Page 137 and 138:
Page 139 and 140:
Page 141 and 142:
Page 143 and 144:
Page 145 and 146:
Page 147 and 148:
Page 149 and 150:
Page 151 and 152:
Page 153 and 154:
Page 155 and 156:
System Design VariationsThis chapte
Page 157 and 158:
System Design Variationspressure dr
Page 159 and 160:
System Design VariationsImpact on o
Page 161 and 162:
System Design Variations• Run 7 v
Page 163 and 164:
System Design Variationsmechanical
Page 165 and 166:
System Design Variations• Impleme
Page 167 and 168:
System Design Variationsconventiona
Page 169 and 170:
System Design VariationsFigure 113.
Page 171 and 172:
System Design Variationsbuildings (
Page 173 and 174:
System Design VariationsFor most ap
Page 175 and 176:
System Design VariationsWhile the s
Page 177 and 178:
System Design VariationsFigure 120.
Page 179 and 180:
System ControlsThis chapter discuss
Page 181 and 182:
System Controlssensor from being in
Page 183 and 184:
System ControlsFigure 126. Modulate
Page 185 and 186:
System Controlsfixed enthalpy contr
Page 187 and 188:
System ControlsIf the air-handling
Page 189 and 190:
System ControlsFigure 133. Floor-by
Page 191 and 192:
System ControlsVAV terminal unitsSi
Page 193 and 194:
System Controlspeople in a zone, an
Page 195 and 196:
System ControlsAlternatively, if th
Page 197 and 198:
System Controlsvariable-speed drive
Page 199 and 200:
System ControlsFigure 137. System-l
Page 201 and 202:
System ControlsTable 31. Example of
Page 203 and 204:
System ControlsFigure 139. Morning
Page 205 and 206:
System Controlszone to the unoccupi
Page 207 and 208:
System ControlsThe optimal starting
Page 209 and 210:
System ControlsFigure 143. Fan-pres
Page 211 and 212:
System ControlsTable 36 lists condi
Page 213 and 214:
System Controlsreset to be used dur
Page 215 and 216:
System ControlsFigure 147. Ventilat
Page 217 and 218:
System Controlsdecrease overall sys
Page 219 and 220:
System ControlsFigure 150. Optimize
Page 221 and 222:
GlossaryACH. Air changes per hour.A
Page 223 and 224:
Glossarycondensing boiler. A type o
Page 225 and 226:
Glossaryelectronic air cleaner. Par
Page 227 and 228:
GlossaryMERV. Minimum Efficiency Re
Page 229 and 230:
Glossarypump-pressure optimization.
Page 231 and 232:
GlossaryTR. Cold-spot thermal resis
Page 233 and 234:
ReferencesAir-Conditioning and Refr
Page 235 and 236:
References______. 2009. Direct-Driv
Page 237 and 238:
References______. 2008. “ASHRAE S
Page 239 and 240:
Indexchilled-water system 79air-coo
Page 241 and 242:
Indexhumidifiers 126humidity contro
Page 243 and 244:
IndexVAV controlpressure-dependent
Page 246:
Tranewww.trane.comFor more informat
show all

Chilled-Water VAV Systems - HVAC.Amickracing

Create successful ePaper yourself

Delete template?

Save as template?