Troubleshooting: Heating (Heat pumps)
PROBLEM | POSSIBLE CAUSE | TO CORRECT |
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| Thermostat setting. | Set thermostat to a warmer position. |
No heating — fan | Defective thermostat. | Replace — do not attempt to adjust. |
operates. | Compressor not operating. | Check compressor wiring. Check for open internal |
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| or external overload. Check wiring. |
| Defective system switch. | Test system switch |
PROBLEM | POSSIBLE CAUSE | TO CORRECT | |
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| Restricted filter. | Clean as recommended in Owner’s Manual. | |
Insufficient heating. | Outdoor thermostat. | Check if outdoor thermostat is energizing the heating | |
(Applicable models.) | element at its predetermined temperature setting | ||
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| Check control setting. | |
| Fresh air or exhaust door open. |
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PROBLEM | POSSIBLE CAUSE | TO CORRECT | |
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Fan operates in | Inoperative system switch. | Check continuity of switch. | |
"constant" position, but |
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Incorrect wiring. | Check applicable wiring diagram. | ||
not in "automatic" | |||
(MoneySaver). |
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PROBLEM | POSSIBLE CAUSE | TO CORRECT | |
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Temperature varies from | Defective thermostat. | Incorrect differential setting. Replace thermostat. | |
Heat anticipator (resistor) shorted. | Check voltage to resistor. If voltage okay, remove | ||
comfortable to overly | (Applicable models) | resistor from thermostat bulb block. With current on, | |
warm. |
| feel resistor for warmth. If no heat can be felt, | |
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| replace anticipator. |
PROBLEM | POSSIBLE CAUSE | TO CORRECT |
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| Heat anticipator (resistor) shorted. | Disconnect power to unit. Remove resistor from |
| (Applicable models.) | thermostat bulb block. Plug in unit and allow to |
Room temperature |
| operate. Feel resistor for heat. If no heat is felt, |
uneven. |
| replace resistor. |
(Heating cycle) | Wide differential — partial loss of ther- | Replace thermostat and check. |
| mostat bulb charge. |
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| Incorrect wiring. | Refer to appropriate wiring diagram. Resistor is |
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| energized during the "on" cycle of compressor or |
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| fan. |
PROBLEM | POSSIBLE CAUSE | TO CORRECT | |
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| Incorrect wiring. | Refer to appropriate wiring diagram. | |
| Defrost control timer motor not advanc- | Check for voltage at "TM" and "TM1" on timer. If | |
Unit will not defrost. | ing. | voltage, replace control. | |
Defrost control out of calibration. | If outside coil temperature is 25° F or below, and | ||
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| preselected time limit has elapsed, replace the | |
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| defrost control. | |
| Defrost control contacts stuck. | If the contacts remain closed between terminals "2" | |
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| and "3" of the defrost control after preselected time | |
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| interval has passed, replace control. | |
| Defrost control bulb removed from coil, | Reinstall and assure that good bulb to coil contact is | |
| or not making good coil contact. | made. | |
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