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a/c wont turn off

Could either be a relay at the furnace stuck closed and passing power to the condenser, or the contactor at the condenser could be stuck closed.
Good luck-


  • greg_29
    greg_29 Member Posts: 1
    a/c wont turn off

    first timer here hoping to get some help
    my a/c will not turn off
    i checked the wires at the t-stat--furnace and outside unit
    when i switch off at the t-stat outside unit keeps running
    furnace turns off
    i think it is a bad t-stat but want another opinon before i continue
    thank you for your help
  • Eugene Silberstein
    Eugene Silberstein Member Posts: 1,380
    Sounds like

    Since the blower in the furnace turns off when the unit is shut down, the fan relay is operating.

    If you want to check the thermostat, the easiest away to do this is to remove the thermostat from the subbase and disconnect the "Y" wire. Check the outdoor unit. If the unit is still operating, the thermostat is fine and the contactor contacts are stuck in the closed position. If the outdoor unit is not operating, chances are that you have a defective thermostat.

    Keep us posted.
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