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  1. #1
    Join Date
    Jun 2005
    Posts
    3
    Hi all,

    I have a dual unit/zone AC/Heat setup at my home. I believe they are Puron units (but that could just be the refrigerant in them). I bought two new rite temp touch screen thermostats.

    I swapped out the downstairs unit and it worked great. However a couple days later when swapping the upstairs unit, I forget to put the mounting plate on before I wired the back of the thermostat. Power at the breaker was turned back on to test. However, when removing the wires to do this I spaced on switching the power off at the breaker box, and apparently shorted one or more of the wires together. Now, I can hear the thermostat click on and off, but I can't get that AC unit to fire up, AZ or heat.

    The thermostat was not on when this happened, only the wiring plate, so I doubt the problem is with it. I am suspecting I may have caused a blown fuse (hopefully there is a fuse!) in the transformer or controller board?

    Does this sound right? My wiring setup is a 4 wire (R G W Y, with a blue colored "C" wire as well).

    I guess step one is pull out the continuity tester? Then see if I did permenant damage.

    Just want to run this by those more knowledgable than myself in case I'm on the wrong track.

    Thanks!

  2. #2
    Join Date
    Apr 2005
    Posts
    53
    Not a fuse in the transformer, a fuse or the transformer.

  3. #3
    Join Date
    Apr 2005
    Location
    Inland Empire,CA
    Posts
    56
    possibly blown control board fuse, fried transformer or fan center.

  4. #4
    Join Date
    Jun 2005
    Posts
    3
    Ok. Thanks! Would believe it is most likely either a popped fuse or fried stepdown transformer from allowing stat wires to come in contact under power? I've just never goofed that much before, embarrassing.

  5. #5
    Join Date
    Jun 2005
    Posts
    3
    I guess that answers it, you must have hit reply just as I did, lol. Thanks!

  6. #6
    Join Date
    Oct 2001
    Posts
    6,966
    with the subbase still mounted and the wires on the terminals read R to C should be a constant 24VAC,if you have that the 24Vs is up from the furnace.if not head down or up to it and check the same R and C which is straight 24vs to the subbase.check the secondary right out of the TR should be 24Vs,if there is no fuse to read shut the power off,remove the low side wires from the unit,and try to read continuity and that secondary coil wire within the TR.if you have continuity on the 24Vs but no 24Vs when powered? check the primary side(115V)with power off with continuity again.
    "when in doubt...jump it out" http://www.youtube.com/watch?v=U1qEZHhJubY

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