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Low suction

Discussion in 'Residential' started by jamesyarbrough, Sep 22, 2017.

  1. frozensolid

    frozensolid Psychologist's Dream

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    12,268
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    Earth
    Has anyone suggested checking that the supply air registers are all open.

    PS Rheems have a charging for orifice systems if you don't use it you will always have problems in low ambient.

    What puzzles me is your orifice is too small, comp too big. But you have a flooded coil. Your head should be low not normal.
     
    Last edited: Sep 23, 2017
    Anita sannich and knave like this.
  2. Catpower

    Catpower The Crowd Pleaser

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    22,249
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    in the Cabana
    Is it keeping the place cool? Is ti freezing up? If it is a yes and no answers fill out invoice collect money leave for next job

    It was ****ed up from the git go so let it ride until it quits
     
  3. Texas-Tech

    Texas-Tech Official Geezer*

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    17,627
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    duhh
    :D
     
    Last edited: Sep 23, 2017
  4. Anita sannich

    Anita sannich Exceptionally average

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    Spokane WA
    Nevermind
     
    Last edited: Sep 23, 2017
  5. jamesyarbrough

    jamesyarbrough Amateur Gynecologist

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    3,707
    Location:
    Denison TX


    come on man. Give me a little credit. :D
     
    knave likes this.
  6. knave

    knave Undeterred

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    8,166
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    Out for a rip
    Well did you? :stick:
     
  7. Texas-Tech

    Texas-Tech Official Geezer*

    Messages:
    17,627
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    duhh
    I was just having a margarita reading this thread again and realized you said 5 degrees of sh, I totally wasn't thinking.
    Screw my last response, I was totally wrong
     
  8. jamesyarbrough

    jamesyarbrough Amateur Gynecologist

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    Denison TX
    I've pretty well came to the conclusion it's a hacked up pos and it's never gonna be right but its at the end of its life anyway so **** it
     
  9. Daryl_Dixon

    Daryl_Dixon New Member

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    3,780
    You say the compressor was changed. I wonder what sort of fittings were used in that immediate vicinity. Anything causing a restriction? Wrong diameter? Homemade couplings? Crimplings? Etc...
     
  10. crackertech

    crackertech assholiness *

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    I have a TM on that pay up.:chairshot:
     
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  11. jamesyarbrough

    jamesyarbrough Amateur Gynecologist

    Messages:
    3,707
    Location:
    Denison TX


    Just some shitty welds
     
  12. Catpower

    Catpower The Crowd Pleaser

    Messages:
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    Location:
    in the Cabana

    I am sure you looked at the piston since you had the number, but one time there was a unit that had everybody stumped (not really stumped too lazy to check it out good) so it got handed off to me, the problem all along was a sliver of silphos was in the hole in the piston causing a restriction
     
  13. knave

    knave Undeterred

    Messages:
    8,166
    Location:
    Out for a rip
    Once had a similar situation.
    The guy was a planned maintenance customer. Had a compressor go out a couple of years after the install. Whoever changed the compressor saw liquid slugging the compressor and pulled out charge.

    One day on a maintenance I found no subcooling, a very high suction pressure, and low superheat.

    I convinced the owner that something was wrong even though he hadn’t noticed the issue. (Very well insulated home)

    Pulled the piston, a big gobbler of solder was in between the piston and the seat. Was a heat pump it must have blew in there in heat mode one winter.
     
  14. knave

    knave Undeterred

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    Out for a rip
    Had to add about 2 lbs after the fix.
     
  15. Daryl_Dixon

    Daryl_Dixon New Member

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    3,780
    I wondered if you'd notice. :pbj:
     
  16. jamesyarbrough

    jamesyarbrough Amateur Gynecologist

    Messages:
    3,707
    Location:
    Denison TX

    It had some black stuff around the seating area so I changed it. Same size tho
     
  17. jpb2

    jpb2 Dog Tard *

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    47,179
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    within the bounds of reality
    Long shot. Fire it up and unplug the blower. Watch the frost pattern
     
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  18. R/HVAC

    R/HVAC selfemployed

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    459
    Location:
    W-S , NC
    James - Jeff is correct about the supply take-off size being a problem. Been through it several times on installs I did not do. There is no static regain if the duct is not same size as the outlet on the air handler. I made mine 14" long at the least, then transitioned to existing size and had no problem. Don't forget to bend the blower outlet flanges up or out if you install new duct of correct size. If there is room you could install a sleeve over the blower outlet inside the existing duct but that is close to hacking. The heat pump systems had to have refrigerant added in the summer and charge removed in the winter if the duct was not made correctly.
    PS - this was discussed on channel 3 about 10 yrs. ago.
     
    jpb2 likes this.
  19. Rather B Riding

    Rather B Riding Behind bars

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    568
    I'm glad I'm not doing residential anymore. Some of the stuff you see is just major hack. Reading this thread and putting myself in your shoes, wanting to do the customer right. Here's what I think and would do. I would first verify that the blower is 3 ton drive. Then I would change the Piston to a TVX. You could just change the Piston but you would have to guess the size. Somewhere between a 68 and 72 would probably get you real close but Piston is matched to the compressor. The compressor btu rating doesn't match the original so the charts in the unit are useless.
     
    Anita sannich likes this.
  20. tuna

    tuna New Member

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    2,914
    That's a good thought. If one of the circuits was stopped up you would see the symptoms described.
     
    jpb2 likes this.