TROUBLESHOOTING – HEATING OPERATION
Symptom | Cause | |
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Thermostat does not call for heat | ||
HEAT and make a call for heat. | ||
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Heating does not come on at all | RH terminal not connected – see wiring diagrams. | |
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Heating equipment power not on. | ||
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Auxiliary Heat does not come on | High Balance point limit – set balance point higher than outdoor temperature | |
or disconnect outdoor temperature sensor during system checkout. | ||
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| Furnace plenum sensor keeps fan on – normal. | |
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Fan stays on after heat call | Blower Extension for humidifier operation. Verify that the message | |
"HUMIDIFYING" appears at the message center, alternating with the time | ||
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| and date and any other currently active messages. | |
Fan comes on before heat starts, or | Change position of ELEC/GAS dip switch – ELEC for electric heat systems | |
(fan on with heat call) or to GAS for fossil fuel systems where the fan is | ||
Fan does not come on with heat | ||
controlled internally by the heating equipment. | ||
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Cooling comes on instead of heat | Reversing valve wiring. | |
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Miswiring – check wire colors at thermostat and HVAC equipment. | ||
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Takes longer than 4 minutes for auxiliary | SINGLE/MULTI dip switch set incorrectly – set to SINGLE for | |
heat to come on after compressor heat. | compressor systems. | |
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