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Gas furnace blower motor won't start when thermometer set to heat

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03-10-14, 08:20 PM

WilliamY

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Gas furnace blower motor won't start when thermometer set to heat

My gas furnace's blower motor won't come on when the thermometer switch is set to "heat" and the fan switch set to either "on" or "auto". The motor itself is ok because it works fine when the thermometer switch is set to either "off" or to "cool" and fan is switched to "on".
When the thermometer's switch is at "heat" position and its fan switch is set at "on", the furnace's vent motor starts and then there are some noises from the ignition and/or gas nozzle, but neither the blower motor would start nor the gas would be ignited.
Thanks,

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03-10-14, 09:06 PM

Houston204

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Tell us more about your system and what it is doing.

Post the furnace make and model number and describe in detail the sequence of events as the furnace tries to start.

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Gas and Oil Home Heating Furnaces
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