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508187-01

Issue 2116

Page 1 of 51

SERVICE MANUAL

A80UH2E / 80G2UHE

 

(P) 508187-01

*P508187-01*

Table of Contents

Technical Specifications - A80UH2E

 ...........................

2

Technical Specifications - 80G2UHE

 ...........................7

Parts Arrangement

.....................................................

12

Unit Components

 .......................................................13

Flame Sensor

 ............................................................

23

Gas Valve

 ..................................................................

23

Heating Components

 .................................................

23

Placement and Installation

 ........................................

29

Start-Up

 .....................................................................

29

Heating System Service Checks

 ...............................30

Typical Operating Characteristics

 ..............................34

Maintenance

 ..............................................................35

Wiring and Sequence of Operation

 ...........................

39

Field Wiring and DIP Switch Settings

 ........................

42

Troubleshooting

 .........................................................46

This is a safety alert symbol and should never be ignored. When you see this symbol on labels or in manuals, be alert to 

the potential for personal injury or death.

Electric shock hazard. 
Can cause injury or death. Before attempting 

to  perform  any  service  or  maintenance, 

turn  the  electrical  power  to  unit  OFF  at 

disconnect  switch(es).  Unit  may  have 

multiple power supplies.

 WARNING

As with any mechanical equipment, contact with sharp 

sheet  metal  edges  can  result  in  personal  injury. Take 

care  while  handling  this  equipment  and  wear  gloves 

and protective clothing.

 CAUTION

Improper  installation,  adjustment,  alteration,  service 

or maintenance can cause property damage, personal 

injury  or  loss  of  life.  Installation  and  service  must  be 

performed by a licensed professional HVAC installer (or 

equivalent), service agency or the gas supplier.

 WARNING

Summary of Contents for 80G2UHE

Page 1: ...e this symbol on labels or in manuals be alert to the potential for personal injury or death Electric shock hazard Can cause injury or death Before attempting to perform any service or maintenance turn the electrical power to unit OFF at disconnect switch es Unit may have multiple power supplies WARNING As with any mechanical equipment contact with sharp sheet metal edges can result in personal in...

Page 2: ...H2E090B16 88 000 69 000 57 000 46 000 80 0 4 1 2 120 60 1 15 8 2 40 3 4 140 A80UH2E110C16 110 000 86 000 72 000 58 000 80 0 4 1 2 120 60 1 15 8 2 40 3 4 152 A80UH2E110C20 110 000 87 000 72 000 58 000 80 0 5 1 2 120 60 1 15 10 0 40 1 156 Note For vent length and clearances to combustibles please reference installation instructions Note Filters and provisions for mounting are not furnished and must ...

Page 3: ...fm Watts 0 00 1375 340 1350 240 1110 190 970 93 780 50 0 10 1350 346 1325 254 1100 194 940 104 725 57 0 20 1330 346 1310 264 1080 200 895 113 680 64 0 30 1315 353 1280 272 1060 204 860 118 610 70 0 40 1300 368 1250 283 1040 212 810 125 550 76 0 50 1285 369 1220 293 1010 222 765 132 510 78 0 60 1260 384 1190 301 975 227 725 140 460 83 0 70 1240 391 1150 314 950 236 680 147 400 89 0 80 1210 399 1120...

Page 4: ...70 1050 239 905 193 0 70 1520 467 1255 344 1110 284 1000 249 840 202 0 80 1470 474 1215 352 1050 294 935 258 765 211 A80UH2E110C16 External Static Pressure in w g Air Volume Watts at Various Blower Speeds High Black Medium High Brown Medium Blue Medium Low Yellow Low Red cfm Watts cfm Watts cfm Watts cfm Watts cfm Watts 0 00 1780 349 1570 248 1465 190 1370 169 1250 131 0 10 1750 365 1540 260 1420 ...

Page 5: ...0 00 2175 590 2050 410 1850 310 1695 275 1510 195 2175 605 1930 420 1785 320 1675 260 1500 195 0 10 2158 607 1943 421 1778 328 1650 283 1461 205 2129 628 1892 441 1733 345 1627 288 1458 209 0 20 2131 620 1897 436 1719 345 1591 299 1405 215 2091 649 1838 458 1691 360 1586 297 1407 220 0 30 2085 639 1847 456 1678 354 1563 308 1351 228 2072 660 1806 471 1631 371 1529 313 1353 232 0 40 2055 652 1806 4...

Page 6: ...01 2 Stage 80 UH DF Propane Gas 11K47 Natural to LP Kits 2 Stage 80 UH DF 0 7500 ft 11K48 2 Stage 80 UH DF 7501 10 000 ft 11K47 LP to Natural Kits 2 Stage 80 UH DF 77W10 Downflow Specific Air Filters 14 5 51W06 17 5 51W07 Downflow Combustible Flooring Base 14 5 11M59 17 5 11M60 Night Service Kits 2 Stage 22J94 Horizontal Suspension Kit 80 90 51W10 External Filter Rack Kits 1 pack 16 x 25 1 841018 ...

Page 7: ...0 1 2 136 80G2UH090BE16 80G2UH090BE16L 88 000 69 000 57 000 46 000 80 0 4 1 2 120 60 1 15 8 2 40 3 4 140 80G2UH110CE16 110 000 86 000 72 000 58 000 80 0 4 1 2 120 60 1 15 8 2 40 3 4 152 80G2UH110CE20 80G2UH110CE20L 110 000 87 000 72 000 58 000 80 0 5 1 2 120 60 1 15 10 0 40 1 156 Note For vent length and clearances to combustibles please reference installation instructions Note Filters and provisi...

Page 8: ...Watts cfm Watts 0 00 1605 313 1475 240 1320 173 1050 99 865 60 0 10 1565 323 1430 251 1270 185 995 108 800 68 0 20 1515 334 1380 264 1225 196 935 115 730 76 0 30 1475 347 1340 275 1170 207 870 124 645 83 0 40 1435 360 1300 285 1120 215 805 133 550 91 0 50 1395 369 1250 295 1065 225 715 140 470 98 0 60 1355 378 1205 307 1010 235 655 147 395 101 0 70 1305 391 1160 318 935 246 560 156 345 107 0 80 12...

Page 9: ...2 1140 270 1050 239 905 193 0 70 1520 467 1255 344 1110 284 1000 249 840 202 0 80 1470 474 1215 352 1050 294 935 258 765 211 80G2UH110CE16 External Static Pressure in w g Air Volume Watts at Various Blower Speeds High Black Medium High Brown Medium Blue Medium Low Yellow Low Red cfm Watts cfm Watts cfm Watts cfm Watts cfm Watts 0 00 1780 349 1570 248 1465 190 1370 169 1250 131 0 10 1750 365 1540 2...

Page 10: ...m Watts 0 00 2175 590 2050 410 1850 310 1695 275 1510 195 2175 605 1930 420 1785 320 1675 260 1500 195 0 10 2158 607 1943 421 1778 328 1650 283 1461 205 2129 628 1892 441 1733 345 1627 288 1458 209 0 20 2131 620 1897 436 1719 345 1591 299 1405 215 2091 649 1838 458 1691 360 1586 297 1407 220 0 30 2085 639 1847 456 1678 354 1563 308 1351 228 2072 660 1806 471 1631 371 1529 313 1353 232 0 40 2055 65...

Page 11: ...W01 2 Stage 80 UH DF Propane Gas 11K47 Natural to LP Kits 2 Stage 80 UH DF 0 7500 ft 11K48 2 Stage 80 UH DF 7501 10 000 ft 11K47 LP to Natural Kits 2 Stage 80 UH DF 77W10 Downflow Specific Air Filters 14 5 51W06 17 5 51W07 Downflow Combustible Flooring Base 14 5 11M59 17 5 11M60 Night Service Kits 2 Stage 22J94 Horizontal Suspension Kit 80 90 51W10 External Filter Rack Kits 1 pack 16 x 25 1 841018...

Page 12: ...ssure Switch Combustion Air Inducer Gas Valve and Manifold Assembly Limit Switch under collector box Collector Box Heat Exchanger Indoor Blower and Motor Assembly installed in cabinet Make Up Box Constant Torque Indoor Blower Motor removed from cabinet Two Stage Integrated Control ...

Page 13: ... provides overcurrent protection to the transformer T1 The breaker is rated at 3A at 32V If the current exceeds this limit the breaker will trip and all unit operation will shutdown The breaker can be manually reset by pressing the button on the face See Figure 3 Figure 3 Circuit Breaker CB8 PRESS TO RESET Integrated Ignition Control A92 Shock hazard Disconnect power before servicing Control is no...

Page 14: ...r purge and warm up time between trials of 35 seconds After a total of five trials for ignition including the initial trial the control goes into Watchguard Flame Failure mode After a 60 minute reset period the control will begin the ignition sequence again NOTE During abnormal conditions such as low supply voltage or low outdoor temperatures and the low fire pressure switch does not close the com...

Page 15: ...UICK CONNECT TERMINALS NEUTRALS 120 VAC NEUTRAL HUM UNPOWERED NORMALLY OPEN DRY CONTACTS LI 120VAC INPUT TO CONTROL ACC 120VAC OUTPUT TO OPTIONAL ACCESSORY THERMOSTAT CONNECTIONS TB1 DS DEHUMIDIFICATION SIGNAL W2 HEAT DEMAND FROM 2ND STAGE TSTAT W1 HEAT DEMAND FROM 1ST STAGE TSTAT R CLASS 2 VOLTAGE TO TSTAT G MANUAL FAN FROM TSTAT C TSTAT SIGNAL GROUND CONNECTED TO TRANSFORMER GRD TR CHASSIS GROUN...

Page 16: ...15 2 STAGE COMPR W951 HEAT PUMP W914 DEHUM CUT FOR OPTION SELECTION 1 2 3 4 5 6 ON W1W2 G Y2 Y1 C C DH L O DS R W1 W2 G Y2 Y1 C C R L DH 7 1 ON ON ON ON 90 SECOND HTG BLOWER OFF DELAY 1 2 3 4 5 6 7 ON 1 2 3 4 5 6 7 ON THERMOSTAT SELECTION 1 STAGE THERMOSTAT TIMED STAGING SEE SW 2 TWO STAGE THERMOSTAT 1 2 3 4 5 6 7 1 2 3 4 5 6 7 ON ON BLOWER ON DELAY 30 SEC FIXED 1 2 3 4 5 6 7 ON SENSE IGN CAI2 CAI...

Page 17: ...ncy problems System resumes normal operation 5 seconds after fault recovered E115 Low 24V Control will restart if the error recovers 24 Volt Power Low Range is 18 to 30 volts Check and correct voltage Check for additional power robbing equipment connected to system May require installation of larger VA transformer to be installed in furnace air handler Clears after fault recovered E117 Poor ground...

Page 18: ...sure good unit ground Alert clears after current heat call has been completed E241 Flame sensed out of sequence Flame still present Shut off gas Check for gas valve leak Replace if necessary Alert clears when fault is recovered E250 Limit switch circuit open Check for proper firing rate on furnace Ensure there is no blockage in heater Check for proper air flow If limit not closed within 3 minutes ...

Page 19: ...splayed 10 minutes after entering the flame sense mode Integrated Control DIP Switches Integrated Control DIP Switches A80UH2E 80G2UHE L units are equipped with a two stage integrated control This control manages ignition timing heating mode fan off delays and indoor blower speeds based on selections made using the control dip switches and jumpers The control includes an internal watchguard featur...

Page 20: ...gs Switches 6 and 7 Continuous Fan Mode Continuous fan speed can be controlled by changing DIP switch positions Table 7 provides DIP switch settings for continuous fan mode Continuous Fan Mode Switch 6 Switch 7 Low Heat Speed Factory Off Off Low Cool Speed Off On High Heat Speed On Off High Cool Speed On On Table 7 Continuous Fan Mode Settings Onboard Links W914 Dehum Onboard link W914 is a clippa...

Page 21: ...e less than 20mA Troubleshooting the Motor Troubleshooting the motor is an easy process Follow steps below 1 Shut off power to unit 2 Remove input plugs P48 and P49 from motor See Figure 8 for troubleshooting procedure If correct voltage is present in tests 1 and 2 and motor is not operating properly replace motor The motor is not field repairable If replacing the indoor blower motor or blower whe...

Page 22: ...t 3 Check for 120 volts across terminals L1 and Neutrals on the integrated control If voltage is present problem is with the harness If voltage is not present problem may be may be with the integrated control Switch thermostat to CONTINUOUS FAN MODE Check for 24 volts across terminal C on input plug P48 and speed tap used for continuous fan 1 2 3 4 or 5 on input plug P49 If 24 volts is not present...

Page 23: ...e type valve must be used 24VAC terminals and gas control knob are located on the valve A wire harness connects the terminals from the gas valve to the electronic ignition control 24V applied to the terminals energizes the valve Inlet and outlet pressure taps are located on the valve A regulator adjustment screw is located on the valve LPG change over kits are available from Allied Kits include bu...

Page 24: ...508187 01 Issue 2116 Page 24 of 51 Figure 9 Heating Components Gas Valve Gas Orifices Sensor Ignitor Burners Rollout Switches ...

Page 25: ...e manifold and check resistance of the ignitor Reading should be betwenn 39 and 70 ohms If reading is correct then there is a problem with the wiring between the jack plug anf the control If reading is not correct the issue is the ignitor Meter set to ohms Test 3 Checking voltage to ignitor Insert meter probes into terminals 1 and 5 use small diameter probes in order to not damage plug Check volta...

Page 26: ...L METER Red Collar Indicates Positive Leads To Control Sensor Terminal Flame Sensor Flame Sensor Wire Integrated Control Remove Sensor Wire from Integrated Control and Connect Alligator Clip to Frame Sensor Lead Flame Sensor Terminal Remove Sensor Wire from Integrated Control and Connect Alligator Clip to Terminal on Control ...

Page 27: ...ure 12 A80UH2E 80G2UHE L series units are equipped with a dual combustion air pressure switch first and second stage located on the CEHB The switch is connected to the cold end header box by means of flexible silicone hoses It monitors negative differential pressure across the cold end header box orifice The switches are a single pole single throw pressure switches electrically connected to the in...

Page 28: ...y consists of orifice plate proving switch gasket and combustion air inducer then reinstall the mounting screws See unit Installation Instructions for more detail The combustion air pressure switch must be moved for horizontal discharge air left position IMPORTANT Figure 13 FLOW AIR vent pipe FLOW AIR Vent Pipe FLOW AIR Vent Pipe Vent Pipe Vent Pipe vent pipe In all positions route the wires away ...

Page 29: ...ccess panel 6 Move gas valve switch to OFF See Figure 14 7 Wait five minutes to clear out any gas If you then smell gas STOP Immediately call your gas supplier from a neighbor s phone Follow the gas supplier s instructions If you do not smell gas go to next step 8 Move gas valve switch to ON See Figure 14 Figure 14 Gas Valve GAS VALVE SHOWN IN ON POSITION INLET PRESSURE POST HIGH FIRE ADJUSTMENT S...

Page 30: ...the gas supply line CAUTION Do not over torque 800 in lbs or under torque 350 in lbs when attaching the gas piping to the gas valve WARNING Testing Gas Piping In case emergency shutdown is required turn off the main shut off valve and disconnect the main power to unit These controls should be properly labeled by the installer IMPORTANT When pressure testing gas lines the gas valve must be disconne...

Page 31: ...Flow Approximate Furnace should operate at least 5 minutes before checking gas flow Determine time in seconds for two revolutions of gas through the meter Two revolutions assures a more accurate time Divide by two and compare to time in Table 10 If manifold pressure matches Table 12 and rate is incorrect check gas orifices for proper size and restriction Remove temporary gas meter if installed NOT...

Page 32: ...units 2 Natural gas high altitude orifice kit required 3 A natural to L P propane gas changeover kit is necessary to convert this unit Refer to the changeover kit installation instruction for the conversion procedure NOTE Units may be installed at altitudes up to 4500 ft above sea level without modifications Table 12 Manifold Pressure and Line Pressure at Various Altitudes Capacity High Altitude P...

Page 33: ... of load indicates a poor or partial ground Compare the readings to Table 14 If the readings exceed the maximum shown in Table 14 make repairs before operating the furnace 2 In addition measure the AC voltage from Line Hot to Line Neutral spade terminals on the integrated control See Figure 16 This voltage should be in the range of 97 to 132 Vac Furnace Status Measurement VAC Expected Maximum Powe...

Page 34: ...g plate Figure 17 TEMPERATURE RISE Supply Duct Temperature Return Duct Temperature _ Temperature Rise SUPPLY AIR Temperatures RETURN AIR External Static Pressure 1 Tap locations shown in Figure 18 2 Punch a 1 4 diameter hole in supply and return air plenums Insert manometer hose flush with inside edge of hole or insulation Seal around the hose with permagum Connect the zero end of the manometer to...

Page 35: ... also cause the limit to trip more frequently during the winter and the indoor coil to freeze in the summer resulting in an increase in the number of service calls Before using any filter with this system check the specifications provided by the filter manufacturer IMPORTANT Cabinet Width Filter Size Side Return Bottom Return 14 1 2 16 x 25 x 1 14 x 25 x 1 17 1 2 16 x 25 x 1 21 20 x 25 x 1 Table 1...

Page 36: ...ce inspection to ensure proper combustion and operation Consult Service Literature for proper combustion values 14 Verify operation of CO detectors and replace batteries as required Perform a general system test Turn on the furnace to check operating functions such as the start up and shut off operation 1 Check the operation of the ignition system inspect and clean flame sensor Check microamps bef...

Page 37: ...am Begin from the burner opening on each clam Steam must not exceed 275 F 12 To clean burners run a vacuum cleaner with a soft brush attachment over the face of burners Visually inspect inside the burners and crossovers for any blockage caused by foreign matter Remove any blockage Figure 19 shows burner detail 13 To clean the combustion air inducer visually inspect and using a wire brush clean whe...

Page 38: ...508187 01 Issue 2116 Page 38 of 51 Figure 21 Remove 5 screws if necessary either side of cabinet 1 2 3 4 5 ...

Page 39: ...508187 01 Issue 2116 Page 39 of 51 Wiring and Sequence of Operation 045 12 070 12 090 12 090 16 110 16 110 20 COMFORT SYNC THERMOSTAT ...

Page 40: ...se and send a signal to the integrated control The integrated control initiates a 30 second second stage recognition delay 6 At the end of the recognition delay the integrated control energizes the combustion air inducer at high speed The control also checks the high fire second stage pressure switch to make sure it is closed The high fire second stage gas valve is energized and the indoor blower ...

Page 41: ...r begins a 5 second low speed post purge The field selected indoor blower off delay begins The indoor blower operates at the low fire heating speed 7 When the combustion air post purge period is complete the inducer and the HUM contacts are deenergized The indoor blower is de energized at the end of the off delay as well as the 120 ACC terminals Figure 22 Heating Operation with Two Stage Thermosta...

Page 42: ...itch 2 to set sceond stage heat ON delay OFF 7 minutes ON 12 minutes ON CUT ON BOARD LINK W915 2 STAGE COMPR T STAT FURNACE TERM STRIP OUTDOOR UNIT Not required on all units 1 Heat 2 Cool with t stat with dehumidification mode NOTE Use DIP switch 2 to set sceond stage heat ON delay OFF 7 minutes ON 12 minutes ON CUT ON BOARD LINK W915 2 STAGE COMPR CUT ON BOARD LINK W914 DEHUM T STAT FURNACE TERM ...

Page 43: ...LINK W915 2 STAGE COMPR CUT ON BOARD LINK W914 T STAT FURNACE TERM STRIP OUTDOOR UNIT o Not required on all units 2 Heat 1 Cool with t stat with dehumidification mode OFF CUT ON BOARD LINK W914 T STAT FURNACE TERM STRIP OUTDOOR UNIT o Not required on all units 2 Heat 1 Cool OFF DO NOT CUT ANY ON BOARD LINKS T STAT FURNACE TERM STRIP OUTDOOR UNIT Not required on all units NOTE Do NOT make a wire co...

Page 44: ...RNACE TERM STRIP HEAT PUMP 67M41 Y H L Y2 D B L Y2 T T outdoor sensor Dual Fuel Two Stage Heat Pump Thermostat w dual fuel capabilities Capable of 2 stage gas heat control OFF CUT ON BOARD LINK W951 HEAT PUMP CUT ON BOARD LINK W915 2 STAGE COMPR FURNACE TERM STRIP HEAT PUMP out blue 67M41 H L Y2 D B L Y2 T T outdoor sensor T STAT Y2 NOTE Do NOT make a wire connection between the room thermostat L ...

Page 45: ...NACE TERM STRIP HEAT PUMP 67M41 Y H L Y2 D B L Y2 T T outdoor sensor Dual Fuel Two Stage Heat Pump Thermostat w dual fuel capabilities Capable of 2 stage gas heat control with dehumidification mode OFF CUT ON BOARD LINK W914 DEHUM CUT ON BOARD LINK W951 HEAT PUMP CUT ON BOARD LINK W915 2 STAGE COMPR T STAT FURNACE TERM STRIP HEAT PUMP 67M41 H L Y2 D B L Y2 T T outdoor sensor Y2 out blue Y2 NOTE Do...

Page 46: ...S INTERRUPTED OR T STAT IS CYCLED OFF ON FOR 3 SEC MINIMUM NO YES FIRST LOW STAGE PRESSURE SWITCH CONTACTS OPEN NO GAS VALVE OFF COMBUSTION AIR INDUCER OFF INDOOR BLOWER OFF CONTROL REMAINS UNTIL PRESSURE SWITCH IS DETECTED OPEN STATUS ERROR CODE 2 4 YES GAS VALVE OFF COMBUSTION AIR INDUCER OFF INDOOR BLOWER OFF CONTROL WILL NOT ATTEMPT SECOND STAGE OPERATION DURING THIS HEAT DEMAND FIRST STAGE OP...

Page 47: ...N WITHIN 4 SECONDS AFTER GAS VALVE OPENS 0 19 microamps GAS VALVE OFF COMBUSTION AIR INDUCER ON INDOOR BLOWER OFF STATUS LED HEARTBEAT HAS CONTROL FAILED TO SENSE FLAME FOR FIVE CONSECUTIVE TRIES DURING A SINGLE HEAT DEMAND YES THERMOSTAT CALLS FOR HEAT STATUS LED HEARTBEAT Refer to box A on previous page YES FLAME PRESENT NO HAS CONTROL RESET IGNITION SEQUENCE FOUR 4 TIMES WATCHGUARD MODE STATUS ...

Page 48: ...TES NO YES FIRST STAGE HEAT DEMAND SATISFIED GAS VALVE OFF COMBUSTION AIR INDUCER OFF FOLLOWING POST PURGE INDOOR BLOWER OFF WITH DELAY STATUS LED PULSE YES SECOND STAGE HEAT DEMAND SECOND STAGE HEAT DEMAND REQUIRED NO SECOND STAGE PRESSURE SWITCH CLOSED ABNORMAL FLASH CODE NOTE IF SECOND STAGE PRESSURE SWITCH WAS ORIGINALLY FOUND CLOSED ABNORMAL CODE WILL FLASH SECOND STAGE PRESSURE SWITCH CLOSED...

Page 49: ...GE THERMOSTAT MODE DIP SWITCH SET AT SINGLE YES YES FIRST AND SECOND STAGE HEAT DEMAND SATISFIED SIMULTANEOUSLY STATUS LED HEARTBEAT YES GAS VALVE OFF COMBUSTION AIR INDUCER OFF AFTER 5 SECOND LOW SPEED POST PURGE PERIOD INDOOR BLOWER OFF DELAY INITIATED ON LOW HEAT SPEED STATUS LED HEARTBEAT DEMAND FOR HEAT SATISFIED POWER ON STAND BY STATUS LED PULSE YES SECOND STAGE HEAT DEMAND SATISFIED STATUS...

Page 50: ...NSER FAN ENERGIZED NO IS THERE PROPER GROUND YES NO INDOOR BLOWER ENERGIZED ON FIRST STAGE COOL SPEED AFTER 2 SECOND DELAY FIRST STAGE DEMAND FOR COOL SATISFIED NO THERMOSTAT CALLS FOR SECOND STAGE COOL COMPRESSOR AND CONDENSER FAN DE ENERGIZED INDOOR BLOWER DE ENEGIZED YES INDOOR BLOWER RAMPS UP TO SECOND STAGE COOL SPEED SECOND STAGE DEMAND FOR COOL SATISFIED YES UNIT RETURNS TO FIRST STAGE COOL...

Page 51: ...WER SWITCHES TO LOW HEAT SPEED FIRST STAGE HEAT DEMAND SATISFIED YES NO THERMOSTAT CALLS FOR SECOND STAGE HEAT YES INDOOR BLOWER SWITCHES TO HIGH HEAT SPEED AFTER 30 SECOND RECOGNITION PERIOD SECOND STAGE HEAT DEMAND SATISFIED YES YES INDOOR BLOWER RAMPS DOWN TO LOW HEAT SPEED INDOOR BLOWER RAMPS TO FIRST STAGE COOLING SPEED AFTER A 2 SECOND DELAY FIRST STAGE COOL DEMAND SATISFIED YES NO SECOND ST...

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