Just moved into my condo about 6 months ago, replaced the old thermostat with a newer Hunter model # 42999B digital thermostat. AC worked great all summer long (I live in FL). I finially get around to turning on the Heat and it kicks on at the correct temp just fine, but it will not turn off (I hear the thermostat CLICK but the heat keeps on running). I even tried disconnecting the thermostat and removing it from the wall (just snaps off) the heat will continue to run and run - I usually wait at least 4-5 minutes before giving up - I know it can continue to run for several minutes after it's suppose to go off. The Heat/OFF/AC switch has no affect either, and lowering the temp has no affect.
The only way I can turn off the heat is by turning off the circuit breaker, and waiting about 2 mintues, then I will hear a "click" from the Weathermaster eletric heat unit - then I can turn the breaker back on - and it stays off. If I turn on the breaker too soon the heat/fan comes right back on (even with thermostat removed!).
I am guessing this has nothing to do with the thermostat, what should I start looking at on the eletric heat unit? I have an old Weathermaster model CFEAH18-10 unit.
I have a basic 4 wire thermostat, One weird thing I tried lastnite was removing the jumper wire from the Rh and Rc on the thermostat - the unit will actually turn off ONCE automatically, but once it comes back on it won't turn off - I tested this 4 times!!! Then I have to manually reset the sequence with the circuit breaker.