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17:
67:
that distributes the hot air through the building. Each room has an outlet from the duct system, often mounted in the floor or low on the wall – some rooms will also have an opening into the cold air return duct. Depending on the age of the system, forced-air gas furnaces use either a
84:
to pre-heat the incoming furnace airflow, using a second heat exchanger. This increases the efficiency (energy delivered into the building vs. heating value of gas purchased) to over 90%. An incidental beneficial effect is that the exhaust flue is much smaller and can be made of plastic pipe since
119:
Residential and commercial buildings located in rural and remote areas do not often use natural gas forced hot air systems. This is due to the financial impracticality of running natural gas lines many miles past areas of relatively sparse habitation. Usually these rural and remote buildings use
109:
Plastic outlet for a condensing natural gas hot air furnace. Not all the water vapor is condensed; some freezes at the outlet. This vent contains a coaxial combustion air inlet pipe. Blowing snow can block the pipe, but the furnace control can detect this condition and prevent the burner from
72:
starts and stops the furnace to regulate temperature. Large homes or commercial buildings may have multiple thermostats and heating zones, controlled by powered dampers. A digital thermostat can be programmed to activate the gas furnace at certain times. For example, a resident may want the
68:
pilot light or a solid-state ignition system (spark or hot surface ignition) to light the natural gas burner. The natural gas is fed to buildings from a main gas line. The duct work supplying the hot air (and sometimes cool air if an AC unit is tied into the system) may be insulated. A
93:
The heat exchangers may be damaged by corrosion or metal fatigue from many heating and cooling cycles. A small leak of combustion gases into the heated air can be dangerous to the occupants of the heated space, because of possible carbon monoxide build up.
89:
is much cooler. As a result it can be more easily routed through walls or floors. However, the condensing furnace is more expensive initially because of the extra induced-draft fan and condensate pump required, and the extra heat exchanger in the firebox.
1557:
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134:
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626:
355:
446:
1527:
1341:
721:
285:
183:
1489:
1433:
1428:
1005:
533:
101:
A condensing forced-air furnace; flue pipes are plastic, not metal, because of the low waste-gas temperature.
76:
Simple types of gas-fired furnace lose significant amounts of energy in the hot waste gases. High-efficiency
77:
1050:
601:
522:
481:
1393:
1195:
706:
641:
559:
471:
335:
259:
1542:
1423:
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204:
43:
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850:
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539:
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1010:
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52:
1627:
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611:
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1325:
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671:
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1215:
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310:
8:
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476:
370:
330:
1578:
1522:
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696:
278:
149:
1150:
1105:
860:
855:
785:
681:
517:
320:
179:
97:
80:
condense the water vapor (one of the by-products of gas combustion) and extract the
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950:
656:
554:
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1612:
1584:
1226:
1140:
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651:
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621:
616:
486:
410:
133:
Information on forced air pilot lights and maintenance from GasFurnaceGuide.com
124:
or propane, which is delivered by a truck and stored in a tank on the property.
47:
Older furnaces sometimes relied on gravity instead of a blower to circulate air.
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temperature in their dwelling to rise 15 minutes before returning from work.
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820:
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heating/cooling systems for houses. Sometimes the system is referred to as
242:"FurnacePrices.ca | Canada's Trusted HVAC Reviews & Buyer Guides"
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512:
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1040:
960:
20:
A forced-air gas furnace, of the older, non-condensing type
51:Gas-fired forced-air furnaces have a burner in the
1660:
279:
1046:High efficiency glandless circulating pump
295:Heating, ventilation, and air conditioning
286:
272:
147:
150:"Gravity Furnace Inspection - InterNACHI"
1480:Mold growth, assessment, and remediation
104:
96:
42:
15:
170:
168:
166:
1661:
1353:Programmable communicating thermostat
267:
59:. A blower forces cold air through a
1475:Mechanical, electrical, and plumbing
197:"How to Light a Furnace Pilot Light"
163:
13:
1336:Minimum efficiency reporting value
14:
1680:
1378:Standard temperature and pressure
1091:Packaged terminal air conditioner
627:Passive daytime radiative cooling
356:Heat pump and refrigeration cycle
252:
114:
447:Absorption-compression heat pump
174:Bill Johnson, Kevin Standiford,
1342:Normal temperature and pressure
722:Vapor-compression refrigeration
1669:Residential heating appliances
234:
219:
189:
141:
1:
1490:Testing, adjusting, balancing
1434:Building information modeling
1429:Building services engineering
1006:Ground-coupled heat exchanger
534:Demand controlled ventilation
482:Building insulation materials
127:
1051:High-pressure cut-off switch
602:Ice storage air conditioning
523:Dedicated outdoor air system
227:"High Efficiency Gas Boiler"
176:Practical Heating Technology
27:heating systems are used in
7:
1394:Thermostatic radiator valve
1196:Thermostatic radiator valve
707:Underfloor air distribution
642:Radiant heating and cooling
560:Energy recovery ventilation
472:Automobile air conditioning
336:Domestic energy consumption
10:
1685:
1543:Institute of Refrigeration
1424:Architectural technologist
896:Electrostatic precipitator
1605:
1596:Volatile organic compound
1571:
1498:
1455:Environmental engineering
1419:Architectural engineering
1402:
1250:
1221:Ultra-low particulate air
806:Automatic balancing valve
753:
734:Variable refrigerant flow
586:Heat recovery ventilation
529:Deep water source cooling
439:
301:
178:, Nelson Education, 2008
38:
1643:Template:Home automation
1465:Kitchen exhaust cleaning
1161:Solar-assisted heat pump
761:Air conditioner inverter
540:Displacement ventilation
431:Vapour pressure of water
416:Thermal destratification
1638:World Refrigeration Day
1485:Refrigerant reclamation
1414:Architectural acoustics
1358:Programmable thermostat
1290:Clean air delivery rate
1186:Thermal expansion valve
1101:Pressurisation ductwork
1011:Ground source heat pump
452:Absorption refrigerator
258:From howstuffworks.com
1628:Glossary of HVAC terms
1590:Sick building syndrome
1470:Mechanical engineering
1181:Smoke exhaust ductwork
612:Mixed-mode ventilation
231:Saturday, 5 June 2021
111:
102:
48:
21:
1648:Template:Solar energy
1326:Intelligent buildings
1285:Carbon dioxide sensor
672:Room air distribution
492:Central solar heating
108:
100:
46:
19:
1450:Duct leakage testing
1440:Deep energy retrofit
1384:Thermographic camera
1321:Infrared thermometer
796:Air source heat pump
745:Water heat recycling
311:Air changes per hour
1316:HVAC control system
1306:Home energy monitor
1280:Building automation
1066:Inverter compressor
728:Variable air volume
637:Passive ventilation
607:Kitchen ventilation
507:Constant air volume
477:Autonomous building
78:condensing furnaces
1579:Indoor air quality
1523:ASTM International
1460:Hydronic balancing
1237:Wood-burning stove
1116:Radiator reflector
901:Evaporative cooler
712:Underfloor heating
697:Thermal insulation
201:Gas Furnace Guides
112:
103:
49:
22:
1656:
1655:
1572:Health and safety
1151:Scroll compressor
1106:Process duct work
861:Convection heater
856:Condensing boiler
786:Air-mixing plenum
682:Solar combisystem
518:Cross ventilation
321:Building envelope
244:. 19 August 2020.
207:on 1 January 2013
63:and then through
1676:
1618:Building science
1373:Smart thermostat
1368:Room temperature
951:Fireplace insert
657:Radon mitigation
555:Electric heating
550:District heating
545:District cooling
462:Air conditioning
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281:
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203:. Archived from
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148:Gromicko, Nick.
145:
33:"forced hot air"
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1613:ASHRAE Handbook
1601:
1585:Passive smoking
1567:
1500:
1494:
1406:
1404:
1398:
1252:
1246:
1227:Whole-house fan
1141:Run-around coil
1136:Reversing valve
1081:Mechanical room
1071:Kerosene heater
1061:Infrared heater
991:Gasoline heater
931:Fan filter unit
846:Condensate pump
831:Centrifugal fan
749:
652:Radiant heating
647:Radiant cooling
622:Passive cooling
617:Microgeneration
487:Central heating
435:
411:Thermal comfort
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1363:Psychrometrics
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1260:Air flow meter
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1038:
1036:Heating system
1033:
1028:
1023:
1018:
1016:Heat exchanger
1013:
1008:
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998:
993:
988:
983:
981:Gas compressor
978:
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968:
963:
958:
953:
948:
943:
938:
933:
928:
923:
918:
916:Expansion tank
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908:
903:
898:
893:
888:
883:
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873:
868:
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836:Ceramic heater
833:
828:
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719:
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709:
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689:
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679:
677:Solar air heat
674:
669:
667:Renewable heat
664:
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654:
649:
644:
639:
634:
629:
624:
619:
614:
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604:
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583:
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576:Forced-air gas
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428:
426:Thermodynamics
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403:
398:
396:Psychrometrics
393:
388:
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378:
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368:
363:
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351:Gas compressor
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346:Fluid dynamics
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253:External links
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139:
138:
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116:
115:Areas of usage
113:
61:heat exchanger
40:
37:
25:Forced-air gas
9:
6:
4:
3:
2:
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1501:organizations
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1445:Duct cleaning
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1299:
1297:
1296:Control valve
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1243:
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1235:
1233:
1230:
1228:
1225:
1222:
1219:
1217:
1216:Turning vanes
1214:
1212:
1209:
1207:
1204:
1202:
1199:
1197:
1194:
1192:
1191:Thermal wheel
1189:
1187:
1184:
1182:
1179:
1177:
1174:
1172:
1169:
1167:
1164:
1162:
1159:
1157:
1156:Solar chimney
1154:
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926:Fan coil unit
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871:Cooling tower
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723:
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718:
717:Vapor barrier
715:
713:
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708:
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703:
700:
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695:
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692:Solar heating
690:
688:
687:Solar cooling
685:
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670:
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665:
663:
662:Refrigeration
660:
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632:Passive house
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503:
502:Chilled water
500:
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401:Sensible heat
399:
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392:
389:
387:
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381:Noise control
379:
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361:Heat transfer
359:
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36:
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26:
18:
1623:Fireproofing
1407:and services
1403:Professions,
1301:Gas detector
1201:Trickle vent
1176:Smoke damper
1171:Smoke canopy
1166:Space heater
1096:Plenum space
1031:Heating film
911:Exhaust hood
881:Dehumidifier
821:Blast damper
816:Barrier pipe
791:Air purifier
702:Thermosiphon
581:Free cooling
575:
497:Chilled beam
421:Thermal mass
406:Stack effect
391:Particulates
371:Infiltration
302:Fundamental
236:
221:
209:. Retrieved
205:the original
200:
191:
186:, pp.114-119
175:
154:. Retrieved
152:. InterNACHI
143:
118:
92:
75:
50:
24:
23:
1633:Warm Spaces
1275:Blower door
1253:and control
1251:Measurement
1232:Windcatcher
1206:Trombe wall
1146:Sail switch
1126:Refrigerant
1121:Recuperator
996:Grease duct
956:Freeze stat
941:Fire damper
811:Back boiler
781:Air ionizer
776:Air handler
740:Ventilation
592:Hybrid heat
457:Air barrier
376:Latent heat
87:exhaust gas
82:latent heat
57:natural gas
29:central air
1389:Thermostat
1311:Humidistat
1242:Zone valve
1211:TurboSwing
1086:Oil heater
1056:Humidifier
986:Gas heater
936:Fan heater
906:Evaporator
891:Economizer
866:Compressor
771:Air filter
754:Components
571:Forced-air
467:Antifreeze
440:Technology
386:Outgassing
326:Convection
211:4 December
184:111180267X
156:2014-06-25
128:References
70:thermostat
55:fueled by
1499:Industry
1348:OpenTherm
1026:Heat pump
1021:Heat pipe
971:Fume hood
946:Fireplace
851:Condenser
801:Attic fan
597:Hydronics
110:starting.
65:duct-work
1663:Category
1606:See also
1331:LonWorks
1265:Aquastat
1131:Register
1111:Radiator
766:Air door
566:Firestop
366:Humidity
341:Enthalpy
331:Dilution
316:Bake-out
304:concepts
122:oil heat
1405:trades,
976:Furnace
841:Chiller
513:Coolant
53:furnace
1558:SMACNA
1518:ASHRAE
1338:(MERV)
1292:(CADR)
1270:BACnet
1223:(ULPA)
1076:Louver
1001:Grille
876:Damper
826:Boiler
724:(VCRS)
525:(DOAS)
182:
39:Design
1598:(VOC)
1592:(SBS)
1581:(IAQ)
1538:CIBSE
1533:BSRIA
1436:(BIM)
1380:(STP)
1344:(NTP)
966:Freon
736:(VRF)
730:(VAV)
588:(HRV)
562:(ERV)
536:(DCV)
509:(CAV)
1553:LEED
1513:AMCA
1508:AHRI
1041:HEPA
961:Flue
886:Duct
213:2012
180:ISBN
85:the
1563:UMC
1548:IIR
1528:BRE
921:Fan
1665::
199:.
165:^
35:.
287:e
280:t
273:v
229:.
215:.
159:.
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