i have central heat and air in my house. for some reason when the thermostat is set at ac, the heat continues to blow and won't shut off. i had to shut it off at the breaker. i just replaced the thermostat and it is still having that problem. help, i am burning up. any ideas or suggestions?
Shorted wiring? Improper wiring? Wrong thermostat? Bad control board? You need someone who knows what they are doing to check this out.
try unhooking the jumper on the thermostat that connects rh and rc (red wire jumper). this is just a quick fix and should work but you will have to jumper back to rh in the winter. good luck
There is a device in the furnace called the temp. delay relay. If this is set wrong it will allow the fan (blower) to run even if the unit is off. It is probably set too low. The purpose of a T D R is to let the blower blow out the excess heat after the burner turns off. It is mounted on the furnace in the heat exchanger area. It has a dial with movable arrows indicating when it comes on and turns off. You should be able to adjust yours if you can locate it. There are some variations of this device, but they all work the same. Good luck and God Bless.
