Rheem heater/cooler does not turn off. Model RRGG-05N24JKR 230V 24A 3/1/1990

My residential roof heater/air conditioner unit does not shut-off the fans when the heater is switch off at the controls. Setting the thermostat to 0-degrees or opening the circuit at the control won't turn off the heater fan, only the gas will shut off. Shutting off the main power supply is the only way to turn it off. Turning it off and on does not help, no clicking is heard from the relays. Normally, it is timed for 1-3 minutes before the fans shuts off, but it doesn't. When it does shuts off, I can hear a click from the relay. The air conditioner works fine.What could be wrong with the circuit?
Thanks
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| My residential roof heater/air conditioner unit does not shut-off | the fans when the heater is switch off at the controls. Setting | the thermostat to 0-degrees or opening the circuit at the control | won't turn off the heater fan, only the gas will shut off. Shutting | off the main power supply is the only way to turn it off. Turning | it off and on does not help, no clicking is heard from the relays. | Normally, it is timed for 1-3 minutes before the fans shuts off, | but it doesn't. When it does shuts off, I can hear a click from | the relay. The air conditioner works fine.What could be wrong | with the circuit?
Most thermostats have a switch which lets you run the fan with the AC neither heating not cooling. Is it off? Also, check the stack switch as it has a similar switch (like a button) that must be pushed in for normal operation.
N
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the contracts are problably arc'd across and stuck on the units 'fan control' or fan control relay. The fan control has a bimetal probe that sticks into the furnace plenum and holds the fan off until the plenum gets warm on the heat cycle..(so you dont get cold air when the furnace first starts)...then keeps the fan running after the gas valve goes off until the plenum cools a bit.
That gismo is probably defunct.
Phil Scott

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| the contracts are problably arc'd across and stuck on the | units 'fan control' or fan control relay. ...
More often some 'fiddly fingers' pulled the manual switch out / on.
N
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