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Defective reversing valve?

Discussion in 'Commercial' started by pipe31, Jun 25, 2009.

  1. pipe31

    pipe31 pipe31

    Messages:
    2,645
    Location:
    kansas
    I was servicing a 10 year old Trane heat pump today. I found the suction line temperature to be 5 degrees higher when it came out of the reversing valve than before it entered. I took both temps close to the valve. The reason I checked this was my superheat was high and the subcooling was good. Could the discharge be leaking through the valve?
  2. Bender

    Bender Promoted to Regional Turd Polisher

    Messages:
    22,882
    Location:
    Mamby Pamby Land
    Could be Pipe.....

    I think it's 3 degrees on filter driers and 5 or 7 on reversing valves....

    Sorry....I guess I'm not much help....:redface:
  3. Swampfox

    Swampfox Trailer Trash

    Messages:
    29,767
    Location:
    Hell Hole Swamp
    5 is acceptable

    TXV or piston?
  4. Iraqveteran

    Iraqveteran Moneyshot

    Anything above 3° is an indication of a possible restriction.


    Easiest way to tell is to take a small magnet and put it on the valve body where the slide is located. Then switch it back and forth a few times to see how far its sliding...


    Also check your coil......could be a weak coil
  5. Iraqveteran

    Iraqveteran Moneyshot


    That was gonna be my next question.
  6. pipe31

    pipe31 pipe31

    Messages:
    2,645
    Location:
    kansas
    It is aTXV
  7. Swampfox

    Swampfox Trailer Trash

    Messages:
    29,767
    Location:
    Hell Hole Swamp
    its probaly underfeeding, suction pressure low?
  8. pipe31

    pipe31 pipe31

    Messages:
    2,645
    Location:
    kansas
    Suction pressure was 60. High side was 260. Subcooling was 10. Superheat was 39.

    condenser is 20 ft higher than the evap. Suction line is about 50ft. 1 1/8.
    5 ton unit.
  9. Iraqveteran

    Iraqveteran Moneyshot

    Heat up the valve sensing bulb and see if the superheat comes down.


    Is the sensing bulb properly mounted on the suction line??? With copper or brass straps????....not tie straps.

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