Results 1 to 9 of 9
  1. #1

    Possible Causes for Compressor Repeated On/Off Cycle

    Hi all,

    The compressor of a walk-in cooler is acting strange. It keeps turning off and on in repeated short cycles. I don't know if the problem has to do with the refrigerant or not. The refrigerant is R-22. I checked the section pressure and it read 60psig. I'm not sure what is going on. If anyone can give me some advice, that would be much appreciated. Thank you.

  2. #2
    Join Date
    Jul 2007
    Location
    The Hot South
    Posts
    1,372
    Is the cooler maintaining temp?

  3. #3
    Join Date
    Sep 2008
    Location
    Western PA
    Posts
    25,943
    Quote Originally Posted by R123 View Post
    Is the cooler maintaining temp?
    Not likely with a 60 pound suction pressure...


    I've got a suspicion. Is the compressor unit very hot?

  4. #4
    Join Date
    Jul 2007
    Location
    The Hot South
    Posts
    1,372
    The reason I was asking is because he could have a leaking liquid line solenoid valve or compressor reed valves and the compressor could be short cycling on the LP switch in the off cycle. The cut in setpoint could be above 60.

  5. #5
    Thank you all for your replies. I rechecked the unit.

    If the compressor continues to act this way, it will kill the capacitor. This will cause the compressor to not run, and this will affect the temperature of the unit. Otherwise, the temperature is fine. Even so, the compressor unit is not very hot, but it is warm.

    The low pressure switch is fine. The cut in setpoint for the low pressure switch is set to 30psig.

    Although, the head pressure fluctuates from 300psig to over 450psig. I think this causes high pressure switch to cut off and on. What can cause the head pressure to fluctuate as such?

  6. #6
    Join Date
    Dec 2011
    Location
    Grass Lake, MI
    Posts
    254
    That head pressure is very high! Is the condenser coil restricted and dare I ask, is the condenser fan motor operating correctly?


    Sent from my iPhone using Tapatalk 2

  7. #7
    Join Date
    Sep 2008
    Location
    Western PA
    Posts
    25,943
    Quote Originally Posted by gialieu View Post
    Thank you all for your replies. I rechecked the unit.

    If the compressor continues to act this way, it will kill the capacitor. This will cause the compressor to not run, and this will affect the temperature of the unit. Otherwise, the temperature is fine. Even so, the compressor unit is not very hot, but it is warm.

    The low pressure switch is fine. The cut in setpoint for the low pressure switch is set to 30psig.

    Although, the head pressure fluctuates from 300psig to over 450psig. I think this causes high pressure switch to cut off and on. What can cause the head pressure to fluctuate as such?

    This is the condition that I was suspecting.


    I gotta say it this way:

    If you've gotta ask what causes it then you probably aren't qualified to fix it.

    Time to bring a Pro in to take over, boss.


  8. #8
    I'm sorry. I forgot to mention that the condenser motor fan is operating correctly.

  9. #9
    Join Date
    Nov 2007
    Location
    Mississippi
    Posts
    1,401
    Are you sure fan is operating in proper direction?

Tags for this Thread

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