AC IS TURNING ON BY IT SELF AFTER I SWITICH IT OFF, HOW TO SOLVE THIS PROBLEM
Sounds like a problem with the furances circuit board. With the furance powered off, disconnect the two wires at the circuit boards thermostat terminal strip. These are probably red and white wires connected to the "Y" and "C" thermostat terminal strip on the circuit board. These two wires send 24 volts to the outside A.C. condenser unit when the thermstat is se tinto the cooling mode. With the thermostst in the "off: postion measure across the "Y" & "C" terminals at the furances thermostat terminal strip. If you have voltaged than either the board or thermostst has failed. The next step to determine which has failed is this. Disconnect all the thermostat wires at the furance. To check the heating circuit jumper across the "R" & "W" terminals, the furance should fire off for the heating circuit and run non stop beacause the thermostat is no longer controlling it and is isolated from the furance. Now remove the jumper and jumper across the "R" &"Y" terminals, the blower should run at your furance for the cooling mode and you should have 24 volts across the "Y" & "C" terminals for the outside A.C. condenser compresor contactor.Next check for blower operation by jumpering across the "R" & "G" terminals. If everything checks outs than the thermostst is the problem. Tou may also want to check the control wiring at the thermostts , furance & out side condenser unit. If the wiring has connnected somewhwre between these points or at the terminal connection this may also be bring on the A.C. when the thermostat is in the "off position.
Feb 13, 2011 |
Hitachi Air Conditioners