Page 1 of 4 1234 LastLast
Results 1 to 13 of 53

Hybrid View

  1. #1
    Join Date
    Jan 2011
    Location
    tt, west indies
    Posts
    127

    CVHE320 PURGE UNIT urgent

    got a cvhe 320 and purge unit temps are like 72, 60 degrees f for the lowest wenever system tries to fully load it shuts off on hi pressure purge is not comin on (cuz temp is above 22) but what can cause this to happen sensors are reading ok i check it with another tester and the probes are ok, i even went as far as to add some refrigerant yesturday , this made it worse of course any advice?

  2. #2
    SFTB is offline Bad email address, please contact Admin to fix
    Join Date
    Sep 2011
    Posts
    18
    I would put a gauge on condenser and verify that pressure is actually higher than panel reads when running. Its hard to say if there's air with limited info. When you say purge isn't coming on does that mean not pumping out? All I can say is if the purge is running and suction temp is not dropping then possibly purge TXV could be bad. Subcooling could prove that. I suspect purge valves are open from what you state. Verify there is air and submit more info.

  3. #3
    Join Date
    Jan 2011
    Location
    tt, west indies
    Posts
    127
    THE manual guage is reading the same. Purge compressor running its jus not pumping out which means there iss no air but still, the hi pressure issue is still there, this morning it was 92f, water temp was 51 dropped setpoint to 46 wen system loads pressure gradualy goes up to 16 and cut off on hi press cutout. i really dont hav much experience with the purge unit changed the purge drier yesturday incase it was saturated, at this point im totally lost

  4. #4
    Join Date
    Jan 2011
    Location
    tt, west indies
    Posts
    127

    Thumbs up

    Quote Originally Posted by mr hottstepper View Post
    THE manual guage is reading the same. Purge compressor running its jus not pumping out which means there iss no air but still, the hi pressure issue is still there, this morning it was 92f, water temp was 51 dropped setpoint to 46 wen system loads pressure gradualy goes up to 16 and cut off on hi press cutout. i really dont hav much experience with the purge unit changed the purge drier yesturday incase it was saturated, at this point im totally lost
    well i went back to the site today and met the unit purging on its own i loaded it up and condenser pressure is 13.5, 95% current and system is purging , .so according to the service bullitin "after you change the drier wait 72 hours to allow system to remove moisture properly",so the drier was definately saturated .. (i saw that a little to late) as luck would have it today is the 3rd day since i installed the drier. guys im so sorry for wasting your time ,but i thank you soo much for all the help and advice you gave me, if any of yall ever comin to d caribbean holla at me ill hook u guys up good ..

  5. #5
    Join Date
    Jan 2011
    Location
    tt, west indies
    Posts
    127
    now its onto changing out the bearings on the other cvhe, any body got a manual for that by chance? although i think trane might send a bullitin with the bearings, but i wanna change the seals in it as well , can or if u dont have a manual can any of u guys tell me if the seal to impeller clearences are the same as the cvhf?

  6. #6
    Join Date
    Feb 2010
    Location
    MEXICO
    Posts
    472
    is likely to have moisture refrigeration system purge unit, the temperature should be 22 F suction temp unit purge air to condense

  7. #7
    Join Date
    Jan 2011
    Location
    tt, west indies
    Posts
    127
    so ure saying that althought the suction temp is 92degf , and condensing pressure on unit is high the purge unit is workin ok?.
    i now remembered something i didnt check to see if the purge is undercharged, don't have my ir meter today so i cant check sub cooling .Question if purge unit is short on refigerant for some reason will i get this , highpressure problem and will purge temp be high as well?

  8. #8
    Join Date
    Aug 2009
    Location
    Prattville, Alabama
    Posts
    2,069
    You say that at this point you are totally lost. I agree. Your problem is high pressure, yet you have not given any info concerning saturated condenser refrigerant temperature, or entering and leaving condenser water temperatures, or entering and leaving condenser water pressures. In other words, your problem may not be with the purge unit. I can't tell from here because I don't see where you have verified the presence of air. You should have a qualified tech take a look at it.

  9. #9
    Join Date
    Jan 2011
    Location
    tt, west indies
    Posts
    127
    Quote Originally Posted by Nuclrchiller View Post
    You say that at this point you are totally lost. I agree. Your problem is high pressure, yet you have not given any info concerning saturated condenser refrigerant temperature, or entering and leaving condenser water temperatures, or entering and leaving condenser water pressures. In other words, your problem may not be with the purge unit. I can't tell from here because I don't see where you have verified the presence of air. You should have a qualified tech take a look at it.

    here are the readings,
    evap pressure 16hg
    cond press-13.5psig
    chwe-58degf diff 9degf
    chwl-51degf
    con-in-96degf
    con-out-86degf diff 10degf
    current limit setpoint is 81%
    water temp set at 50degf

    but my question still remains why isnt purge unit picking up non condensables and purging on its own? ill check the sub cooling thursday wen i go back there

  10. #10
    Join Date
    Mar 2011
    Posts
    259
    Quote Originally Posted by mr hottstepper View Post
    here are the readings,
    evap pressure 16hg
    cond press-13.5psig
    chwe-58degf diff 9degf
    chwl-51degf
    con-in-96degf
    con-out-86degf diff 10degf
    current limit setpoint is 81%
    water temp set at 50degf

    but my question still remains why isnt purge unit picking up non condensables and purging on its own? ill check the sub cooling thursday wen i go back there
    because there may not be any non-condensables!

    Are you sure about your entering condenser water temp and leaving condenser water temp?

    96* entering water would probably cause your high condenser pressure.

    You also need to check entering and leaving condenser water PRESSURE. What is the pressure differential? Too low flow will also cause high condenser pressure.

    Is the chiller surging?

    What are the approaches?

  11. #11
    Join Date
    Jan 2011
    Location
    tt, west indies
    Posts
    127
    Quote Originally Posted by TheChillerMan View Post
    because there may not be any non-condensables!

    Are you sure about your entering condenser water temp and leaving condenser water temp?

    96* entering water would probably cause your high condenser pressure.

    You also need to check entering and leaving condenser water PRESSURE. What is the pressure differential? Too low flow will also cause high condenser pressure.

    Is the chiller surging?

    What are the approaches?
    those are the correct wtr temps most of the chillers ive worked on here run with those temps, the ambient temp here is between 85 to 88degf, i cant confirm the water pressure cause guages are screwed, but if i run the back up machine it works fine with the jus about the same condensing temps,the condenser tubes were cleaned couple months ago so. we have good water pressure(assumed), alright heat exchange in tower, thats why i was suspecting the purge unit

  12. #12
    Join Date
    Mar 2011
    Posts
    259
    Quote Originally Posted by mr hottstepper View Post
    those are the correct wtr temps most of the chillers ive worked on here run with those temps, the ambient temp here is between 85 to 88degf, i cant confirm the water pressure cause guages are screwed, but if i run the back up machine it works fine with the jus about the same condensing temps,the condenser tubes were cleaned couple months ago so. we have good water pressure(assumed), alright heat exchange in tower, thats why i was suspecting the purge unit
    I was just verifying because you said your ENTERING water was 96*.

    Verify your water flow.

    If that is good then check condenser approach.

    Compare actual liquid temp to condenser pressure converted to temp. If there is a difference of more than 1-2 degrees then you may have air in the chiller. The wider the difference the more air you may have.

    If you have air now check out the purge unit.

    Troubleshooting the purge deserves a whole thread of it's own.

  13. #13
    Join Date
    Jan 2011
    Location
    tt, west indies
    Posts
    127
    sorry 96 entering the cooling tower, which would be 96dgf leaving the condenser , sorry abt that

Page 1 of 4 1234 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