Results 1 to 12 of 12
  1. #1
    Join Date
    May 2004
    Posts
    20

    Hmm

    I would like to know why on some reach in freezers I am getting frost back all the way to the compressor.3 hp system with receiver charged until sight glass has no bubbles. Isn't the TXV supposed to control liquid in the suction line.

  2. #2
    What's your superheat back at the unit? This temp will tell you whether or not you are getting liquid floodback to your compressor. Or not.

    Jus cause the line is icing, doesnt mean it's liquid flooding back.
    It's probably just cause it's so cold.


    You want thirty degrees, superheat, back at the unit.

  3. #3
    Join Date
    Jan 2004
    Location
    Earth
    Posts
    4,879
    TXV controls superheat.
    A Diamond is just a piece of coal, that made good under pressure!

  4. #4
    Join Date
    Jun 2001
    Location
    San Diego, CA
    Posts
    1,149
    Superheat.

    if you want a box at zero degrees, then obviously your coil must be colder - say 10 degrees below zero. Now, if Copeland asks for 20 degrees of superheat at the compressor then that suction temperature needs to be
    -10degrees plus 20 or plus 10degrees. That suction line
    better frost or we're living on a different planet.

  5. #5
    Join Date
    May 2004
    Posts
    20

    Question

    The part I don't get is two freezers next to each other at box temp of -10 F both air cooled with 408 gas and one ices up to the compressor and the other doesn't

  6. #6
    Join Date
    Sep 2001
    Location
    East Stroudsburg, PA
    Posts
    13,215
    I think you need to contact an experienced commercial refrigeration technician for assistance.

  7. #7
    Join Date
    May 2004
    Posts
    20
    Thanks for the tip

  8. #8
    Join Date
    Jul 2001
    Location
    Gold Coast of Connecticut
    Posts
    4,543
    I think the freezer with no frost will be burning up a compressor before the one that has some frost.

  9. #9
    Originally posted by Freezeking2000
    I think the freezer with no frost will be burning up a compressor before the one that has some frost.

    I agree.


    Before I came to this site ... I had a lot of crummy ideas in my head. (DiceMan ... dont even go there!)

    Now it all comes together in a kind of harmony. It all makes sense.

    And I see others finding the same answers.


    There's a lot of "ol wives tales" in our industry about what is right and what is not.


    This is a fantastic site!!!

    BOSS..... Thanks Again!!!!!!!

  10. #10
    Join Date
    May 2000
    Location
    Monmouth Junction-NJ-USA
    Posts
    5,967
    Originally posted by crisrs
    Isn't the TXV supposed to control liquid in the suction line.
    If this is what u think, your customers are in a lot of trouble. Do what dave suggests, get an experiended tech for assistance. RSES offers Refergeration 1 & 2 courses. An execellent option for u.
    If you really know how it works, you have an execellent chance of fixin' er up!

    Tomorrow is promised to no one...

  11. #11
    Originally posted by R12rules

    Jus cause the line is icing, doesnt mean it's liquid flooding back.
    It's probably just cause it's so cold.
    This reminds me of a conversation I had with an appentice about 15 years ago. We went to service a freezer plant that I worked at regularly. Freezer about 1/2 the size of a football feild. 5 Carrier 5H120's. Box temp -10. He freaked and wanted to adjust all of the tx valves cuz there was ice on the suction service valve.

    Had the same talk about suction temp and superheat at the compressor. If the gas is below freezing tewmp there will be ice. End of story. you need to know the actual temp to determine if there is a problem..

  12. #12
    Join Date
    May 2000
    Location
    Monmouth Junction-NJ-USA
    Posts
    5,967
    Some serious education is also needed in the area of DEW point.
    If you really know how it works, you have an execellent chance of fixin' er up!

    Tomorrow is promised to no one...

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