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We have a Lennox G40UH (X) series Gas furnace. I cannot get…

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We have a Lennox G40UH...
We have a Lennox G40UH (X) series Gas furnace. I cannot get the blower to come on so it is not moving air. I tried switching the thermostat to on versus Auto fan, I took the door off and door switch is working and sending power to the board, but the blower motor has an electrical hum when it tries to turn on. The fan free spins when I try to move it manually, the bearings seem fine. Could it be the capacitor or limit switch?
Submitted: 2 years ago.Category: HVAC
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Answered in 14 minutes by:
2/21/2016
HVAC Technician: Tim H., HVAC Professional replied 2 years ago
Tim H.
Tim H., HVAC Professional
Category: HVAC
Satisfied Customers: 3,972
Experience: Experienced in all aspects of HVAC, both residential and commercial.
Verified

Hi, I'm Tim and I'm an HVAC expert here to help answer your question(s). Please provide all the information I ask for since I'm not onsite. At the end of our dialog you will be asked to rate my service, but please wait until then and all your question(s) have been answered satisfactorily. If you are not satisfied, I'd appreciate it if you'd tell me why before leaving a negative rating and allow me to continue to work with you until we are able to both agree on an outcome to follow. Thanks for your business!

It's possible the capacitor is bad. When it should be on, try taping the door switch in so furnace has power and reach in and give the wheel a spin. See if it starts turning on it's own.

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