Page 1 of 2 12 LastLast
Results 1 to 13 of 15
  1. #1

    Oil visible in liquiid line sight glass?

    Hello I am working on a 35 ton packaged roof top unit with a copeland semi hermetic compressor. I got sent to this site, spoke with building operator he has been resetting the oil failure control ( not good!) I checked over system
    -net oil pressure is 50 psig
    -suction pressure is 63 psig (loaded)
    -head pressure is 150 psig
    -compressor amperage is running at RLA
    -liquid line sight glass has visible oil bubbling in it
    -outlet of the txv, distributor is cold and condensation on feeder tubes
    - the compressor does not sound very good, would this be reason for poor oil return

    thanks for help

  2. #2
    Join Date
    Jan 2008
    Location
    Dallas ,Texas
    Posts
    3,667
    What refrigerant we talking here R-22? Seems your head pressure is low and affecting your oil return.

  3. #3
    Join Date
    Mar 2009
    Location
    Mid-Mo
    Posts
    3,428
    Agreed also the head pressure seems low. You haven't given us much to work with though. How can you be sure it's oil and not vapor or liquid refrigerant? How about superheat, outdoor temp, subcooling, etc?

  4. #4
    Join Date
    Aug 2006
    Location
    Mixing oil and fire with a big spoon.
    Posts
    4,012
    net oil pressure (if it is calculated accurately ) is ok (trip is 9 psid)...but how do you know that it is oil that is bubbling in your liquid line sight glass? i have never seen oil 'bubble' except when heated. i suspect that there is at least 1 other problem.
    Last edited by jayguy; 09-25-2012 at 05:32 PM. Reason: cause i wanted to
    It's tube brushing season...93% done (39.35 miles of tubing)...only 1,242 tubes to go!

    Original member of the Raccoon Brotherhood.

    EVERYTHING IS AWESOME!!!

  5. #5
    Join Date
    Nov 2007
    Location
    Mississippi
    Posts
    1,210
    What's the oil level in crankcase sight glass?

  6. #6
    Join Date
    Sep 2008
    Location
    Western PA
    Posts
    24,993

  7. #7
    Join Date
    Oct 2004
    Location
    The Zone
    Posts
    392
    Sight glass could be discolored looking like oil?
    It's Hammer Time!

  8. #8
    Join Date
    Apr 2012
    Location
    winnipeg
    Posts
    1,330
    never seen oil bubble in a sight glass.... oil travels no doubt but seeing it not to likely
    it was working.... played with it.... now its broke.... whats the going hourly rate for HVAC repair

  9. #9
    Join Date
    May 2010
    Location
    Oxford, UK
    Posts
    336
    Seen something similar,



    What oil and refrigerant is the system running on?

  10. #10
    Join Date
    Feb 2012
    Location
    Toronto Canada
    Posts
    1,088
    ^^^^^^^ Click on the video after that one thats called "Refrigeration system full of water" Looks like the guy pulls 6L out of a system he watches the sight glass lower of water LOL

    To the OP I am not sure how you know its oil that's doing that? I have never seen or heard of it. You give some more info someone should give you a lead in the right direction.

  11. #11
    Join Date
    Dec 2010
    Location
    Down by the river
    Posts
    1,579
    Gotta ask, op how do you know its oil.

    But just food for thought compressors usually start pumping oil out just prior to destruction.

    Give us some more info. And why is the oil failure switch tripping? Bad switch, refrigeration problem?

  12. #12
    Join Date
    May 2002
    Location
    evansville indiana
    Posts
    942
    Only time I have seen oil droplets hanging on a sightglass ,when the system was or wasn't running was when I started up a large 134a system that had mineral oil in the comps instead of poe.

    I questioned this BEFORE startup and was ordered to run with it as it was ordered with the correct oil .

    The result was poor or no oil return ,the oil in the sightglass and other issues .

    The result ,,,two days with cases of the correct oil , buckets ,and an oil refractometer and plenty of rags until I had it confirmed the oil ratio was acceptable.
    mikeacman

  13. #13
    Join Date
    Mar 2009
    Location
    Mid-Mo
    Posts
    3,428
    Quote Originally Posted by monkeyspanners View Post
    Seen something similar,



    What oil and refrigerant is the system running on?
    That's really wild, I don't know how I'd react if I saw that for my owns eyes. I'm thinking I'd be getting the recovery pump and tank out.

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