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Furnace fan won't run in manual mode

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02-09-13, 08:38 AM

ruauu2

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Furnace fan won't run in manual mode

I have a thermostat with a mechanical switch for FAN: AUTO/ON - the fan won't turn on when I slide the switch to ON. It does work properly in AUTO mode.

How to troubleshoot, please?

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02-09-13, 09:02 AM

Houston204

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If this problem just started, I would remove the stat and blow out the dust while flipping the fan switch, then brush it off.

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