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Lennox Thermostat 43C78
This part 43C78 is compatible with:
- Product Type:
- Air Conditioner, Central Air Conditioner
- Brands:
- Lennox
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Thermostat Customer Reviews
Common Problems Fixed by the Thermostat
Based on customer reports and repair data, this part commonly fixes these issues:
Air conditioner fan not working
Air conditioner compressor won't run
Air conditioner won't turn off
Air handler not heating
Heat pump not heating
About the Thermostat
The thermostat monitors the temperature of the air. When the air temperature rises above a set point, the thermostat activates a switch to provide power to the fan and compressor. If the thermostat is defective, it may prevent the fan from working. To determine if the thermostat is defective, set the air conditioner to cooling and then use a multimeter to test the thermostat for continuity. If the thermostat does not have continuity while the air conditioner is set to cooling, replace the thermostat. (Note: Some thermostats may also control a heater and, as a result, will have three terminals. Refer to your air conditioner’s wiring diagram for more information.)
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Alternative Part Number(s)
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