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Hello, I am reviewing your question now.
If the furnace has been operating for sometime without this error code, it is likely a bad printed circuit board sending a bogus error code.
You can however do a rudimentary polarity check using a volt meter, check for voltage between the white wire and ground, if you get more than 3 or 4 volts, there a problem in your neutral circuit, inside the furnace or the house.
We can go from here without any time limits, this step one of what could turn out to be many.
There are two blowers, the inducer, and the main blower... if the main blower comes on without the burners on, that points to a bad printed circuit card in most but not all cases..
Tell me how many seconds it takes for the main blower to come on after a call for heat.
We can go from there, and be sure to specify which blower.
Hello again, what were the results of the polarity test I asked you to do?
Next disconnect the red thermostat wire and tell me if the blower still comes on when you engage the door switch or not... if the blower still comes on the printed circuit board is most likely bad, (95% chance of that, but not 100%)
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