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Help Troubleshoot ac wont turn on

I was doing some siding on my house, so I pulled the box off going to compressor. Put it back on and went in house to turn on ac, honeywell thermostat is blank. I measured 220v at the box going to compressor. The only other thing I touched was the refrigeration tubes that run along side of house up to attic, I pulled the shroud off that goes into soffit. Any ideas? Thanks in advance.


    HVACNUT Member Posts: 5,453
    There should be a thermostat wire going to the condenser as well. Its possible the wires got snagged and shorted and blew a fuse in the air handler or furnace, or a bad transformer if it wasn't fused.
    If there's a circuit board in the indoor unit, look for a spade fuse (a car fuse) in the board. But find and repair the short first.
  • GW
    GW Member Posts: 4,618
    edited September 2021
    If the stat is dead, that sums it up. Batteries? 

    It’s possible you grounded the 24v and blew the tranny or fuse on the indoor system (furnace/air handler)

    kinda depends of what caused the stat to bite dust 
    Gary Wilson
    Wilson Services, Inc
    Northampton, MA
    [email protected]
  • Rock
    Rock Member Posts: 46
    I went up to the airhandler and took the cover off, couldn't find ny fuse. I started poking around by the circuit board and the thermostat come on. Not sure what happened or how there was a problem at the air handler , but it works now.
    Thanks for the replies.
  • mattmia2
    mattmia2 Member Posts: 8,826
    Might have jiggled the wiring in the air handler when you moved the refrigerant lines or the control wore down to the condenser. Look for loose control wires connected to the terminals in the air handler.