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How to get my suction pressure from vacuum

More info would help as in what type of ststem are you working on, TXV or cap, filter dryers? etc...

Mike T .


  • Ean Wrightson
    Ean Wrightson Member Posts: 1

    Ean Wrightson needs help on this one. I did a compressor change out. Upon turning on the unit everything works but my suction pressure drops into vacumm.
  • D lux_2
    D lux_2 Member Posts: 230

    LL valve open filter dryer LLine open meatering device closed .Think about how the flow goes through sys. something is stopping it . How bout the rubber plugs in the compressor ? where they removed ?
  • Techman
    Techman Member Posts: 2,144

    Morning All, Ean,is this AC? Refrig ?Freezer?Cap tube ?TXV?
    Maybe ,now you have the symptons of what killed the old compressor. How old was the compressor you replaced?
  • Eugene Silberstein 3
    Eugene Silberstein 3 Member Posts: 1,380
    Definitely in Need....

    ... of more information...

    How much refrigerant was recovered from the system?

    How much refrigerant went back into the system?

    Is the new compressor an exact replacement for the old?

    Different compressors have different internal volumes, which ultimately affects the final refrigerant charge in the system.

    You need to take operating temperatures, pressures and calculate superheat and subcooling to see what's going on.

    Gather the following and let us have another look:

    System refrigerant:


    Outside ambient temperature:

    Condenser saturation temperature:

    Condenser outlet temperature:

    Evaporator saturation temperature:

    Evaporator outlet temperature:

    Return air temperature:

    Supply air temperature:

    Temperature of the suction line near the inlet of the compressor:
  • Empire_2
    Empire_2 Member Posts: 2,343

    On that E-Mail I sent you,..If I could draw like that, I wouldn't have to do HVAC for a living;-) Very 3 D like dont ya think?

    See Ya

    Mike T.
  • Eugene Silberstein 3
    Eugene Silberstein 3 Member Posts: 1,380
    Nothing short of....

This discussion has been closed.