Page 1 of 2 12 LastLast
Results 1 to 13 of 21
  1. #1
    Join Date
    Jan 2011
    Location
    greenville , sc
    Posts
    718

    htpmp no pistion

    im working on a carrier htpmp and the name plate calls for a .061 pistion ID

    and a .052 pistion outdoor ....

    i have located and checked the ID piston at the coil and it is correct ,

    but where the OD piston should be there is no pocket or seat for a piston and the line to the header is straight ( no signs of foul play.) it looks factory....


    am i missing something? the unit isnt cooling at all and im not sure if i should even run this unit in heating , are there units out there that do not use outdoor pistons/ txv's ? is this someones sick joke of a fix?



    guys this thing is wrecking my thought process , help please?
    catch a man a fish , feed him for a day.
    teach a man to fish , ruin a good business opportunity.

  2. #2
    Join Date
    Jan 2011
    Location
    greenville , sc
    Posts
    718
    another question!
    how do i even install a piston on a header with no means of disconnecting other than debrazing?
    catch a man a fish , feed him for a day.
    teach a man to fish , ruin a good business opportunity.

  3. #3
    Join Date
    Feb 2009
    Location
    Tallahassee, FL
    Posts
    6,048
    The piston is usually in the LL service valve on carriers.

  4. #4
    Join Date
    Jan 2011
    Location
    greenville , sc
    Posts
    718
    ok that explains a lot because it seems as if some one changed the LL SV and the compressor two months ago and unit (according to HO) hasnt been right since.............. thanks ill order a new one and install it and the proper piston on thursday . i should have looked into that im an idiot sometimes............

    thank you ,

    J.Hall
    catch a man a fish , feed him for a day.
    teach a man to fish , ruin a good business opportunity.

  5. #5
    Join Date
    Sep 2007
    Location
    NC
    Posts
    28
    SBKold is correct, Check the liquid line service valve outlet for a flare nut. After a pump down you can remove and check for a piston. You might find what you are looking for. Best wish....

    P.S. Could we get some more details on the symptoms of this unit that is not cooling, psi, S/H, S/C, Amb, TD & etc...

  6. #6
    Join Date
    Feb 2009
    Location
    Tallahassee, FL
    Posts
    6,048
    I dont see how that is affecting unit in cool though.

  7. #7
    Join Date
    Jan 2011
    Location
    greenville , sc
    Posts
    718
    i do have one question still...

    with the ID piston being correct and the pressures (r-22) being 72/225

    and the indoor coil only getting saturated about 1/3 then shouldn't / wouldn't liquid be returning to the compressor?
    catch a man a fish , feed him for a day.
    teach a man to fish , ruin a good business opportunity.

  8. #8
    Join Date
    Jan 2011
    Location
    greenville , sc
    Posts
    718
    Quote Originally Posted by Stephen260B View Post
    SBKold is correct, Check the liquid line service valve outlet for a flare nut. After a pump down you can remove and check for a piston. You might find what you are looking for. Best wish....

    P.S. Could we get some more details on the symptoms of this unit that is not cooling, psi, S/H, S/C, Amb, TD & etc...
    ambeint IN SIDE (92*) and OUT SIDE (94*)

    superheat 34* and sub cooling 3*

    psi /g above
    catch a man a fish , feed him for a day.
    teach a man to fish , ruin a good business opportunity.

  9. #9
    Join Date
    Sep 2007
    Location
    NC
    Posts
    28
    The S/C and Head Pressure both look low for the outdoor ambient temps that you have . Is this a split system? if so do they match? also what supply air temp do you have?

  10. #10
    Join Date
    Jan 2011
    Location
    greenville , sc
    Posts
    718
    yes it is a split unit 2-ton carrier htpmp .

    no not a matched coil it is in a mobile home and the coil is a nordyne 024 though.

    and i didn't bother taking the supply temp reading ( if i guessed it is probably 80-90*) it wasn't cooling and i just went back to the odu and started picking my brain about this piston situation.
    catch a man a fish , feed him for a day.
    teach a man to fish , ruin a good business opportunity.

  11. #11
    Join Date
    Jul 2006
    Location
    Glendale, AZ
    Posts
    200
    you said the compressor was replaced... could the id coil be oil logged from the old compressor? and the system slightly under charged...
    If you don't know... ASK!

  12. #12
    Join Date
    Jan 2011
    Location
    greenville , sc
    Posts
    718
    Quote Originally Posted by tranedog View Post
    you said the compressor was replaced... could the id coil be oil logged from the old compressor? and the system slightly under charged...
    when i pumped down the system to check the id piston i back purged the unit from suction to liquid and then liquid to suction and inatalled a biflow filter while doing this. i didnt see anything abnormal in the flush so ...........
    catch a man a fish , feed him for a day.
    teach a man to fish , ruin a good business opportunity.

  13. #13
    Join Date
    Sep 2007
    Location
    NC
    Posts
    28
    Its important to see supply air temp. It will tell you alot. Depending on the SA, I would probably add some refrigerant and see how the system responds over time.

Page 1 of 2 12 LastLast

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •  
Comfortech Show Promo Image

Related Forums

Plumbing Talks | Contractor Magazine
Forums | Electrical Construction & Maintenance (EC&M) Magazine
Comfortech365 Virtual Event