My wife noticed it getting warm and turned the thermostat down. It was set on heat, 76 degrees, she put it below 60's and the unit kept running. I shut it completely off and it kept running. The only way it shut off was by tripping the breaker. We waited a good hour and when I flipped the breaker back on, temp still set low, the heater kicked on (still in off position at the thermostat). What's up?:confused:

Defective thermostat
Shorted thermostat wires
Disconnect R and W wires in furnace then turn back on.
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