Question about Intertherm P3RA-042K Air Conditioner

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I have a Intertherm P3rA-042K that runs the ac at the same time as the heat strips. I have a Honeywell RTH3100c I have the red wire at R the Yellow at Y the Green at G and the W2 at aux. I had a jumper between Aux and E like the manual said but it makes no difference. Also for some reason it was hooked up before with a blue wire joined with the red at the unit and the blue going to B at the thermostat. I removed the blue as i saw no use for it and it still doing the same thing. The unit froze up last night from running both the strips and the ac at the same time.

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  • 5 more comments 
  • tractormanan Nov 06, 2010

    I had red green yellow blue and white coming from the ac. I know white is for the heat blue was hooked in with the red wire.

  • tractormanan Nov 06, 2010


  • tractormanan Nov 06, 2010

    ok it works both the heat strips and the fan are on. But now what?

  • tractormanan Nov 06, 2010

    I think I have it figured out I'm trying to run an ac unit with a heat pump thermostat :/ Guess I'll need to get a different one.

  • tractormanan Nov 06, 2010

    Thanks for the help.

  • tractormanan Nov 06, 2010

    Great help!

  • tractormanan Nov 06, 2010

    Very helpful.



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Red, green, and yellow should all be from AC unit. What other wires do you have there, and are they separate from red , green, yellow?

Posted on Nov 06, 2010

  • 2 more comments 
  • Mike Butler
    Mike Butler Nov 06, 2010

    Remove green and yellow from thermostat, and see what you get. That should remove circuit to compressor and fan on AC.

  • Mike Butler
    Mike Butler Nov 06, 2010

    Do you have a multimeter?

  • Mike Butler
    Mike Butler Nov 06, 2010

    did you try removing G and Y from thermostat?

  • Mike Butler
    Mike Butler Nov 06, 2010

    Wouldn't be the first time a manufacturer told me that a particular thermostat would work, but failed to tell me I'd have to omit something like a 2nd speed on a fan or something.
    Good Luck, let me know how you make out.



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