Results 1 to 6 of 6
  1. #1
    Join Date
    Feb 2007
    Posts
    3

    very low psi in heat mode only

    i have a Tranetwa090a400bc split heatpump ,in cooling mode the unit work great but in heating mode the unit stops on yhe low psi switch so the compresser and outdoor fan stops after 10 sec.or when the psi gets below the switch psi.this unit has 2 txv one inside and one outside.thanks for all and any help.scott

  2. #2
    Join Date
    Apr 2005
    Posts
    517
    Bad TXV or low on charge.

  3. #3
    Join Date
    Sep 2004
    Location
    Kansas City, Kansas, United States
    Posts
    13,833

    heat pump

    check for pressure drops or temperature drops between your INDOOR coil on your liquid line. ofcourse the liquid line is still the same line just reverse flow.
    sounds like it may be the outside txv or a drier.
    most heatpumps do not have a low pressure switch but a LOSS OF CHARGE SWITCH.
    they open at or around 0 psig.
    I do not think your heat pump is empty.
    Also do not forget the built in check valves on the OUTDOOR unit.
    good luck
    Frank
    I WILL SELL WORK,GENERATE BUSINESS, GO GET NEW CUSTOMERS!
    YOU SHUT THE HELL UP AND QUIT RUNNING YOUR MOUTH!

  4. #4
    Join Date
    Feb 2007
    Posts
    3
    thanks, my gut feeling is stuck od txv. i didnt think about the dryer .i put this unit in cooling and it works correct the charge was the first thing i thought so i know by all my tests the charge is ok.this problem is very hard to identify because the unit can not run for any length of time before the low psi cut the compresser out.thanks scott

  5. #5
    Join Date
    Feb 2007
    Location
    Northern NJ
    Posts
    660
    does this unit have a low pressure bypass timer? you may need one, especially if it is as cold where you are as it has been here in the northeast. you may just need a minute or two to build pressure.

  6. #6
    Join Date
    Feb 2007
    Posts
    3
    Help Monday is coming soon>>>

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