Results 1 to 16 of 16
  1. #1
    Join Date
    May 2017
    Location
    Essex
    Age
    38
    Posts
    34
    Rep Power
    0

    Trane control issues perhaps?



    Hi guys

    Have an old air cooled Trane chiller ECGCH250 that's had a retro fit and XP40 fridge used.

    We had an issue when carrying out the HP trip as it wasn't operating correctly and fault 'Mckt2' came up relating to 'pressostat fault'

    We installed a new dual HP LP switch and used OFN to check that the trip operates as it should, which it did, so thought happy days.

    Whilst this was operating chiller didn't throw up the above fault and was recharged.

    Charged up and then the chiller decides to throw the fault up again.

    At a loss, any ideas?

    Controls issue?
    Blocked capillary line?


    Many thanks



  2. #2
    Join Date
    May 2017
    Location
    Essex
    Age
    38
    Posts
    34
    Rep Power
    0

    Re: Trane control issues perhaps?

    Just to add to this, linking out the dual switch removes the fault but worked fine before it was installed.

    Been looking at literature and it states that there should be no sharp bends etc within at least 4" before for flare nut connection into the switch.

    So would oil cause an issue and no let the switch reset possibly?

  3. #3
    Join Date
    May 2017
    Location
    Essex
    Age
    38
    Posts
    34
    Rep Power
    0

    Re: Trane control issues perhaps?

    Image005.jpg

    The old switch is the second one up so I'm wondering if the oil is not draining away properly

  4. #4
    Brian_UK's Avatar
    Brian_UK is offline Moderator I am starting to push the Mods: of RE Site Moderator : and general nice guy
    Join Date
    Mar 2001
    Location
    Dorset
    Age
    69
    Posts
    10,441
    Rep Power
    50

    Re: Trane control issues perhaps?

    R449a seems an odd choice for a liquid chiller, what was the original refrigerant?

    What is the pressure switch set to and what is the pressure that the switch trips at?
    Brian - Newton Abbot, Devon, UK
    Retired March 2015
    Please support http://the100project.net/Home

  5. #5
    Join Date
    May 2017
    Location
    Essex
    Age
    38
    Posts
    34
    Rep Power
    0

    Re: Trane control issues perhaps?

    The original was 407c I believe.

    Trio was set to 20Bar as prvs are rated at 27.5 so wanted to make sure they didn’t lift.

    I find it odd that on the ofn the switch tripped well several times. Then hooking it up to circuit it fails to reset. I’m wondering if oil is not draining out and thus clogging the internals?

  6. #6
    Brian_UK's Avatar
    Brian_UK is offline Moderator I am starting to push the Mods: of RE Site Moderator : and general nice guy
    Join Date
    Mar 2001
    Location
    Dorset
    Age
    69
    Posts
    10,441
    Rep Power
    50

    Re: Trane control issues perhaps?

    I would think that a blocked capillary to the pressure switch is unlikely.

    Have you monitored the pressures to find out which is activating the trip, also does the pressure change after the compressor has stopped? We're working in the dark here.
    Brian - Newton Abbot, Devon, UK
    Retired March 2015
    Please support http://the100project.net/Home

  7. #7
    Join Date
    May 2017
    Location
    Essex
    Age
    38
    Posts
    34
    Rep Power
    0

    Re: Trane control issues perhaps?

    Umm the trip hasn’t activated at all when connected to the circuit. It went into the fault above relating to ‘pressostat’ we then linked out the hp switch and fault disappeared. It’s strange that it’s happned to two hp switches now. I’ll do a little more investigation on it as it seems a long shot

  8. #8
    Brian_UK's Avatar
    Brian_UK is offline Moderator I am starting to push the Mods: of RE Site Moderator : and general nice guy
    Join Date
    Mar 2001
    Location
    Dorset
    Age
    69
    Posts
    10,441
    Rep Power
    50

    Re: Trane control issues perhaps?

    Double/triple check your switch wiring.
    Brian - Newton Abbot, Devon, UK
    Retired March 2015
    Please support http://the100project.net/Home

  9. #9
    Join Date
    Sep 2007
    Location
    Somerset
    Age
    63
    Posts
    4,504
    Rep Power
    38

    Re: Trane control issues perhaps?

    Hi Guys.
    Just to throw a complete curve ball!
    in the old SMM control Manual I have.
    Mckt2 is listed as Hp OR Lp fault - reset HP Switch???
    So check out whether the LP switch is in circuit too.

    Good luck Grizzly
    Despite the High Cost of Living it still remains Popular!

  10. #10
    Join Date
    May 2017
    Location
    Essex
    Age
    38
    Posts
    34
    Rep Power
    0

    Re: Trane control issues perhaps?

    Thanks Brian

    Grizzly, see attached old wiring diagram of said unit.

    Common feeds HP switch, then the switch line of that feeds the LP switch which livens up the 2B20 2 and 3, then the chiller will run.

    We are on J2 line 22 at the bottom.

    20171130_120241.jpg

    Now I have changed the switch for a dual and this is the wiring diagram for new unit, so what would you say?

    20171205_115021.jpg

    Many thanks gents

  11. #11
    Join Date
    Sep 2007
    Location
    Somerset
    Age
    63
    Posts
    4,504
    Rep Power
    38

    Re: Trane control issues perhaps?

    Hi Stretch.
    It is difficult for my tired old eyes to make out the details on your drawing.
    As best as I can Decipher it.
    I would feed X1 in on 1 and out on the common to Junc. 3.
    Basically then if the hp or lp drop out, you should be able to confirm by resting which has the issue!
    Worth a try at least.
    Anyone suggest different, please feel free to suggest other options.


    Grizzly
    Last edited by Grizzly; 06-12-2017 at 07:51 PM.
    Despite the High Cost of Living it still remains Popular!

  12. #12
    Join Date
    May 2017
    Location
    Essex
    Age
    38
    Posts
    34
    Rep Power
    0

    Re: Trane control issues perhaps?

    Thanks grizzly

    I fed common to 1 as instructed by manual, then 2 and 3 being lp and hp. When livened on 1, 2 then becomes live. This line I have taken to x10 that feeds the contractors for the compressors.

    Then I’m stuck with the hp cable as I have no where to place it

  13. #13
    Join Date
    Sep 2007
    Location
    Somerset
    Age
    63
    Posts
    4,504
    Rep Power
    38

    Re: Trane control issues perhaps?

    Hi Stretch.
    Sorry I was not clear enough.
    x1 to 1 an 4 (Common) out to term 3 on the Input. (A1-1)
    I read the other lamp terminals as Fault lamp / Alarm signal circuits.
    1F2Q-4 is I think the Comp Thermal cut out and could be having a part to play in all this?
    That could be your issue all along?
    Hopefully you have a legend to clarify this?

    I am struggling to clearly read the drawing.
    However the switches are all in series so substituting the lp and Hp should be relatively simple.
    good luck Grizzly
    Despite the High Cost of Living it still remains Popular!

  14. #14
    Join Date
    May 2017
    Location
    Essex
    Age
    38
    Posts
    34
    Rep Power
    0

    Re: Trane control issues perhaps?

    Yeah the drawing doesn’t come up big on here for some reason I’ll inbox you if ok just for clarification.

    Yes X1 supplies the original hp switch which hen feeds the lp switch these need to be closed to enable the comps which are 2B 20 connected into X10.

    The only thing I fail to see is if the 4 goes to the X10 to enable when there is a fault on the Hp or Lp where they signs to disable the circuit or am I looking into it too I’m depth? I’ve a 3 core and earth cable to the dual switch

    Thanks

  15. #15
    Join Date
    May 2017
    Location
    Essex
    Age
    38
    Posts
    34
    Rep Power
    0

    Re: Trane control issues perhaps?

    Ok think its dropped lol

    I'll put the common X1 to 1 on the new dual switch, the 4 will then go to the X10 which livens up the compressor motor thermostat then enables the chiller to run.

    So then I'm left with the 2 and 3 which I'm assuming are switch lines to potential alarms.

    When the hp or lp trip this will move 1 over to 2/3

  16. #16
    Join Date
    Sep 2007
    Location
    Somerset
    Age
    63
    Posts
    4,504
    Rep Power
    38

    Re: Trane control issues perhaps?

    You Got it!
    Grizzly
    Despite the High Cost of Living it still remains Popular!

Posting Permissions

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