Results 1 to 13 of 13

Thread: No cool load

  1. #1
    Join Date
    Jul 2015
    Location
    Ireland
    Posts
    201
    Post Likes

    No cool load

    Does anyone know why some York chillers display a 'No cool load' when clearly there is a cool load and sometimes you got to drop the setpoint to start a compressor?

  2. #2
    Join Date
    Mar 2004
    Location
    ottawa canada
    Posts
    3,257
    Post Likes
    Differential to start ?
    The toy chest is officially full ... I got a new toy..... 2007 Aston Martin V8 Vantage and yes it still gives me goosebumps
    You bend em" I"ll mend em" !!!!!!!
    I"m not a service tech.. I"m a thermodynamic transfer analyst & strategic system sustainability specialist
    In the new big shop , greasin', oilin' . tweakin' n shinin' !!

  3. #3
    Join Date
    Jul 2015
    Location
    Ireland
    Posts
    201
    Post Likes
    Thread Starter
    Nope. Had one today. Set point at 7 DegC. Range at 1 DegC. LWT was at 11 DegC. Not controlled by remote set point either. Had to drop set point to 5 before it would kick in a compressor. YLAA chiller.
    Seen it happening on a YCAJ also.

  4. #4
    Join Date
    Aug 2019
    Location
    LA
    Posts
    22
    Post Likes
    Software internal load timers. If load is dropping at current demand timers will stop and start on temp fall speed

  5. #5
    Join Date
    Jul 2015
    Location
    Ireland
    Posts
    201
    Post Likes
    Thread Starter
    But the chiller is off and waiting to start. The CHW temp is climbing and she still doesn't kick in?
    Just sits there with no cool load.

  6. #6
    Join Date
    Aug 2009
    Location
    Prattville, Alabama
    Posts
    3,518
    Post Likes
    Is there some kind of chilled water reset that is affecting the setpoint? So that the "active" setpoint is higher?
    In honor of RichardL: "Ain't 'None' of us as smart as 'All' of us".

  7. #7
    Join Date
    Aug 2019
    Location
    LA
    Posts
    22
    Post Likes
    quote from the book

    1) The display will show the anti-coincidence timer status for the lag compressor, followed by ‘NO COOL LOAD’ until it is called to operate by the control system.

    2) LLSV off

    Internal timers. For what, I’ll try to find out

  8. #8
    Join Date
    Jan 2013
    Location
    United Kingdom
    Posts
    266
    Post Likes
    Was it on local control or remote ?


    Sent from my iPhone using Tapatalk

  9. #9
    Join Date
    Jul 2015
    Location
    Ireland
    Posts
    201
    Post Likes
    Thread Starter
    In local model. She likely would have started. Just that I was on site at the time.
    it had gone to 11 DegC and still said no cool load.
    i had system # 2 switch off as i was doing a service on it. But sys # 1 just sat there with no cool load and the temp was up at 11.

    Dropped it down to 5 and she kicked in the first compressor, put the setpoint back to 7 as that what the site wants and she was fine.
    It has a +/- 1.1 diff.
    BMS just monitors for alarms, everything else is chiller controlled.

  10. #10
    Join Date
    Jan 2013
    Location
    United Kingdom
    Posts
    266
    Post Likes
    Auto lead lag or manual ?


    Sent from my iPhone using Tapatalk

  11. #11
    Join Date
    Jul 2015
    Location
    Ireland
    Posts
    201
    Post Likes
    Thread Starter
    Auto Lead lag Raptyr.
    Auto restart after power failure ect

    There is actually noting wrong with the chiller, just I'd like to know whey it happened.
    I also seen it happening on a YCAJ many moons ago, and never got to the bottom of it.

  12. #12
    Join Date
    Jan 2013
    Location
    United Kingdom
    Posts
    266
    Post Likes
    I would see it happen occasionally on YKs and I never got to the bottom of it , I would reboot and everything was fine for a few more months, updated software too but never knew if that really fixed it. I think the logic gets stuck in a loop and goes around in circles under certain circumstances and you just have to break the cycle to wake it up and get it working normally again.
    We ran on simulators too in York but could not replicate the problem


    Sent from my iPhone using Tapatalk

  13. #13
    Join Date
    Nov 2011
    Location
    East Side
    Posts
    6,714
    Post Likes
    I’ve had 2 YCWS’s at one site do that occasionally. It happens maybe once a year, if that. They’re about 10 years old.

Posting Permissions

  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts
  •