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Manufacturer Part
Lennox Furnace Control Board 39M84
Manufacturer Part
Skill Level
$562.09
Skill Level
Does this part fit my product?
Blower control board.The control board regulates the supply of power to the furnace components. Be sure to check more commonly defective parts before replacing the control board.
$562.09
This part 39M84 is compatible with:
- Product Type:
- Furnace
- Brands:
- Lennox
Related Articles & Videos
Frequently Bought with Control Board
Control Board Customer Reviews
Common Problems Fixed by the Control Board
Based on customer reports and repair data, this part commonly fixes these issues:
Very Likely
Furnace blower runs all the time
Very Likely
Furnace takes too long to heat the home
Likely
Furnace burners won't stay lit
Likely
Furnace blower not running
Likely
Furnace not turning on
Likely
Furnace not heating
Possible
Furnace starts then stops
Possible
Furnace blower is running constantly but there is no heat
Possible
Strange smells coming from furnace
Possible
Furnace is frequently cycling/short cycling
Possible
Furnace circuit breaker keeps tripping
Possible
Furnace wall thermostat not working properly
About the Control Board
The control board has relays that regulate the voltage to each component in the furnace. If the relay that controls the blower motor fails while it is closed, it will send continuous voltage to the blower motor, causing the motor to run continuously. If the control board is at fault, replace it.
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Alternative Part Number(s)
Replaces Part Number 39M8401
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