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The unit makes a humming sound but will not kick on to heat the house at all.

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Hi, W/D here.

A humming noise can indicate that the motor isn't getting the necessary starting kick to start up. This extra starting kick is supplied by the start capacitor.
This can also be a problem with the motor proper. The cheapest thing to try is to replace the start capacitor. It is a can looking device that will be located near the motor, and connected to the motor by two brown wires. Trip your breaker outside for the A/C, and trip the service disconnect in the A/C cabinet. Use insulated tools to remove the wires from the capacitor, and do not touch the terminals with bare fingers as a shock could result, even after the wires are disconnected.
Locate a local appliance parts supply company, and take your old capacitor with you to get a replacement. Capacitors and motors are matched, so it is important to get a replacement with the proper rating. Reconnect the new capacitor and try it out.
A capacitor will cost in the less than, but close to $20 range, and is worthy of a try, and will probably fix your problem. If it is the motor itself, a motor and matched capacitor will cost you around $110, or less, depending on the horsepower of the motor. Again, any local appliance parts supply house, or A/C supply will have the necessary parts, and it is not a hard job to do.
Best regards, --W/D--

Posted on Mar 11, 2011


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