Page 1 of 2 12 LastLast
Results 1 to 13 of 26
  1. #1
    Join Date
    Jul 2009
    Location
    Arizona
    Posts
    81

    Residential Guy needs help with freezer

    Hey guys I went out to look at a freezer for one of my residential costumers today. It's one of those two doors freezers that holds bags of ice I'll get the Model and serial numbers for you tomorrow.

    When I got there the psi was @ 50 and I added more R134A until I got it up to 90 psi @ 80 degrees. I also cleaned the condenser coil that was completely restricted by Dust bunny's.

    The compressor was still not coming on so I went and got a hard start kit and used the cap out of it but still all I get is the compressor trying to start every few seconds but just not coming on.

    I ohmed out the compressor and every thing looks ok.

  2. #2
    Join Date
    Jul 2002
    Location
    Yuma, AZ
    Posts
    2,361
    You added refrigerant when the compressor was not running? Bad idea.
    What was the box temperature when you arrived and the psi was 50 (low side)?
    90 psig corresponds to 150F saturation temperature (not 80F).
    No high side pressure?
    Metering device is....?
    I think you are way over your head on this job.
    Too little data.
    "I have never let my schooling interfere with my education."
    Mark Twain
    More at: http://www.quotationspage.com/subjects/education/

  3. #3
    Join Date
    Oct 2009
    Location
    Arizona
    Posts
    63
    I'm still new to all this and unless my 'PT Buddy' Iphone app. is wrong... It says R134A at 80.0F = 86.7psig and it also says R134A at 90psig = 82.0F...... so where is Lynn Comstock getting the 150F?

    Just asking... because now I'm confused. (I haven't taken the time to see if the Iphone app. matches other PT charts.)

    Anyone care to look them numbers up and tell me what you get? Will anyone care to take the time to let me know how CS came up with 150f if his numbers are correct?

    Thanks,

    "It isn't easy.. this learning stuff... lol"
    Last edited by Robertjn2000; 07-06-2011 at 04:24 AM.

  4. #4
    Join Date
    Sep 2008
    Location
    Western PA
    Posts
    25,386
    Regardless, charging a system that way isn't the correct way to do it.

    Best method would be to pull the charge, evacuate and weigh in the nameplate charge.

  5. #5
    Join Date
    Oct 2009
    Location
    Arizona
    Posts
    63
    Why? If your pressures are OK... why would you suck it all out? (unless you have no idea what has been added to the system?) But doesn't static pressures give you an idea if you have non condensables etc. in the system?


    "still learning"


    PS

    I'm all for pull it out if your in doubt..... (clean that mind up guys.. LOL)

  6. #6
    Join Date
    Jul 2002
    Location
    Yuma, AZ
    Posts
    2,361

    Red face I am truly sorry and chagrined.

    Quote Originally Posted by Robertjn2000 View Post
    I'm still new to all this and unless my 'PT Buddy' Iphone app. is wrong... It says R134A at 80.0F = 86.7psig Correct. and it also says R134A at 90psig = 82.0F Correct....... so where is Lynn Comstock getting the 150F? Dyslexia times two. If I go into detail I would increase the confusion.
    Oops I was incorrectly reading the chart on my computer screen at 105F and typed 150F and failed to notice my typo.
    See how confusing that is

    Quote Originally Posted by Robertjn2000 View Post
    ...But doesn't static pressures give you an idea if you have non condensables etc. in the system?...
    Yes it does. The pressure on pure 134a at a stable temperature should be on the chart within the accuracy of your tools.
    1. Pulling it out and taking the temperature of the recovery tank will test purity.
    2. Pumping the system down into the condenser and leaving tne condeser fan running could do the same. A receiver could mess this all up.

    The advantage of recovery purity test is the refrigerant charge can be exactly weighed back in. That is a huge diagnostic advantage.
    Last edited by lynn comstock; 07-06-2011 at 07:52 AM.
    "I have never let my schooling interfere with my education."
    Mark Twain
    More at: http://www.quotationspage.com/subjects/education/

  7. #7
    Join Date
    Sep 2008
    Location
    Western PA
    Posts
    25,386
    Quote Originally Posted by Robertjn2000 View Post
    Why? If your pressures are OK... why would you suck it all out? (unless you have no idea what has been added to the system?) But doesn't static pressures give you an idea if you have non condensables etc. in the system?


    "still learning"


    PS

    I'm all for pull it out if your in doubt..... (clean that mind up guys.. LOL)
    Small units like this typically have cap tube metering devices.


    Cap tubes require a critical charge.

    You said your condenser was plugged. This can lead to a plugged cap tube.

    The best and fastest way to diagnose charge vs cap tube issues, IMO, is to pull it, weigh it back and evaluate the operation with factory charge installed.

    Your mileage may vary on this, but I can assure you that any attempts to charge to a standing pressure will fail.

  8. #8
    Join Date
    Feb 2008
    Location
    California
    Posts
    2,064
    Quote Originally Posted by sda View Post
    The compressor was still not coming
    Why is the compressor not coming on? What is holding it off? are we assuming it is the low pressure control?

  9. #9
    Join Date
    Feb 2006
    Location
    Phoenix,AZ
    Posts
    2,845
    Compressor sounds like it's locked up. Replace the pump, dryer and captube. Weigh in charge and be done with it. Unless it's a leaker?

  10. #10
    Join Date
    Jul 2009
    Location
    Arizona
    Posts
    81
    Come on guys I'm looking for HELP. I can pull the charge later when I know the Compressor is still good. Any ideas on the compressor? It makes a rumbling sound for a few seconds then stops for a few more.

    heres all the numbers I was able to find on this thing w0 1122862 50

  11. #11
    Join Date
    Jul 2009
    Location
    Arizona
    Posts
    81
    Quote Originally Posted by KB Cool View Post
    Compressor sounds like it's locked up. Replace the pump, dryer and captube. Weigh in charge and be done with it. Unless it's a leaker?
    when you say 'pump' do you mean the compressor? I already condemned the compressor I'm just trying to double check my work.

  12. #12
    Join Date
    Sep 2008
    Location
    Western PA
    Posts
    25,386

  13. #13
    Join Date
    Jul 2009
    Location
    Arizona
    Posts
    81
    Quote Originally Posted by jpsmith1cm View Post
    Well, if the starting components are good and the compressor still won't run......
    I only replaced the cap and not the complet start kit also the cap was bigger but rated for less voltage 130 vs 140 or something like that. Do these thing always need a hard start kit on them to work.

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