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I have a Gibson heat pump 3 ton 2 stage cooling back up 15 k elect I don't know if the blue wire from indoor unit goes on the themostate


  • Spence
    Spence Member Posts: 316
    Blue Wire

    If the blue wire is the common leg of the 24 VAC side, you usually don't need common to the thermostat unless you have lights or a digital screen.
  • taco
    taco Member Posts: 3

    sorry i forgot to turn power on to outdoor unit thanks for your help
  • unclejohn
    unclejohn Member Posts: 1,730