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High suction , normal head pressure

Discussion in 'Residential' started by Randysmit1986, Jun 3, 2017.

  1. coldsnap

    coldsnap -20 on the money

    Messages:
    4,031
    Location:
    Wisconsin
    Is this 410a or 22? Probably not a lot of 22 units out there, but they came with nitro in them. Also, is this piston or txv?
     
  2. 22blood

    22blood red wire nuts only

    Messages:
    1,699
    Was the piston sitting in a plasticbag
     
    knave, jpb2, Texas-Tech and 1 other person like this.
  3. jheatac

    jheatac New Member

    Messages:
    1
    That's my theory!

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  4. pintofstout

    pintofstout New Member

    Messages:
    1,475
    Location:
    Olean, NY
    I don't think he woulda had that decent superheat if it had a piston that was wrong size.

    You check to make sure the evap wasn't a wee bit large for the CU?

    Head is a bit low, too. It does look like the compression is low from my armchair.

    Assuming it's a TXV. Could be an undercharge with the wrong piston too i guess.


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    Randysmit1986 likes this.
  5. jamesyarbrough

    jamesyarbrough Amateur Gynecologist

    Messages:
    3,466
    Location:
    Denison TX
    Maybe high cfm. Maybe bad vanes in the compressor. Id measure cfm and do a pump down.
     
  6. jamesyarbrough

    jamesyarbrough Amateur Gynecologist

    Messages:
    3,466
    Location:
    Denison TX
    Maybe it has a gas furnace that running. Lol
     
    Randysmit1986 and 22blood like this.
  7. Anita sannich

    Anita sannich sugar and spice and all that sh#t

    Messages:
    422
    Location:
    Spokane WA
    Hopefully heatsink was used on the metering device before brazing it in, otherwise that neoprene seal is toast.
     
    Randysmit1986 likes this.
  8. Randysmit1986

    Randysmit1986 New Member

    Messages:
    41
    410a txv, I was thinking system possibly had nitro in it, removed evacuated entire system, recharged-same symptoms
     
  9. Randysmit1986

    Randysmit1986 New Member

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    41
    Txv coil, I have no knowledge of anything before me. House was rehabbed and system put in by whoever. No literature or info from the home buyer on the installing company
     
  10. Randysmit1986

    Randysmit1986 New Member

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    41
    Exhaust is near the condenser it would have melted my face as I checked charge lol
     
  11. pintofstout

    pintofstout New Member

    Messages:
    1,475
    Location:
    Olean, NY
    I think you might be right about poor pumping compressor. Can you pump it down from base valve and see if it can pull a vacuum?


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  12. Randysmit1986

    Randysmit1986 New Member

    Messages:
    41
    Txv ..what throws me off is the high suction with a low load inside at 73*f
     
  13. Randysmit1986

    Randysmit1986 New Member

    Messages:
    41
    I will try that started to rain. I also would like to call Ameristar and see what there thoughts
     
  14. pintofstout

    pintofstout New Member

    Messages:
    1,475
    Location:
    Olean, NY
    That, in conjunction with the normal superheat..... Agreed. Unless the evap were just too big for the CU it seems that it's just not quite pumping enough


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    Fred Meebley and Randysmit1986 like this.
  15. jamesyarbrough

    jamesyarbrough Amateur Gynecologist

    Messages:
    3,466
    Location:
    Denison TX
    How much air is it moving?
     
  16. Randysmit1986

    Randysmit1986 New Member

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    3ton blower
     
  17. R2D2-TX

    R2D2-TX New Member

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    334
    American Standard has had an issue with the TXV sensing bulb being affected by the brazing with the heat affecting the power head diaphragm not reacting properly causing the system to give bad performance.. remedy is replace the TXV and recommended to relocate the sensing bulb outside the cabinet with it connected to a 10 or 2 location and insulate it properly... then charge to specs sub cool
    I believe on a 3 ton it is 8...good luck
     
    Randysmit1986 and Anita sannich like this.
  18. Randysmit1986

    Randysmit1986 New Member

    Messages:
    41
    I spoke with a rep and suggested to look at expansion valve as well, me personally have never seen a txv fail wide open which could be throwing a wrench in my thinking
     
  19. pintofstout

    pintofstout New Member

    Messages:
    1,475
    Location:
    Olean, NY
    How would SH be twenty with an X valve stuck open though


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  20. Randysmit1986

    Randysmit1986 New Member

    Messages:
    41