HVAC Fan won't turn off

Old 01-15-18, 05:43 PM
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HVAC Fan won't turn off

When I am running my heating, the thermostat would reach temperature and the system will switch to blowing cold air. It seems like the furnace is shutting down but the blower keeps working. If I turn heating off through the thermostat, it would still take the fan about 20 minutes to shut down. Similarly, if I change the temperature to a lower setting while hot air is blowing, it would keep blowing cold air. If I keep the heating off and the fan is off, then switch fan to "On" and then to "off" it would go on and off just fine. Is the problem the fan limit switch, the thermostat or something else?
Old 01-15-18, 06:04 PM
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Welcome to the forums.

There are two ways a blower can be controlled..... either a timed function from the control board or a fan/limit control. We'd need a model number to be able to tell you which you have. The model number can be found on an ID tag inside on the sidewall near the burner.

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