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marter
12-07-2010, 07:14 PM
Odd problem with this (I think) its got a new control board in it, I replaced it about 4 months ago and was running fine since today. I was looking at it, was Calling for Y1 and Y2, neither was running though (lights on the control board was on)

no 24v to contactor, reset unit, same thing. Turned unit off put dip swith into "unit test" turned back on, indoor blower comes on and it never cycles to any other systems (cool/heat)

I didn't do a indepth check, had more pressing matters to attend to. it has a low pressure/low ambient switch on it, but it showed it was closed.

Can someone give me a idea, or point me into a good direction for tommorrow.

hvacpope
12-07-2010, 08:23 PM
did you hear the board relays click? make sure there is 24V to the relays and check for continuity, if there is a call for cooling with no error codes showing the cooling relays should close if not the board is shot.

BKS60
12-07-2010, 08:44 PM
No 24v to contactor? How about to and out of pressure switches. Do the condensor fans run, is the blower belt broke, are the filters ok?