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Old chiller, new controller

Discussion in 'Commercial' started by otto, Aug 10, 2013.

  1. otto

    otto Bakery Chef

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    19,866
    Location:
    in a van down by the river
    We have a customer with 3 Carrier recip chillers. 4 compressors each, 2 with unloaders for a total of 6 stages. Needed 8 relays to control staging. Took out the old control and went with Honeywell T775L and expansion module.
    P8090001.JPG P8090002.JPG P8090003.JPG P8090004.JPG P8090005.JPG P8090006.JPG P8090007.JPG P8090008.JPG P8090009.JPG P8090010.JPG

    Hard part was trying to get 2 #16 stranded in the same lug. Had to come up with a different idea and powered relays that received constant power from TB1 120V.
    Should have gotten pic of old wiring diagram, it's a head scratcher for sure! Back on MOnday to wire up the other 2 chillers.
     
  2. otto

    otto Bakery Chef

    Messages:
    19,866
    Location:
    in a van down by the river
    Had a bit of a hard time getting to a satisfactory setting. Stayed with 48° setpoint 8 relays in the loop, 6° throttle range, 60 seconds integral. I understand kinda how the integral plays into the staging but, referencing the return (inlet) water was not responding fast enough and would open freezestat. I'll play with it more on Monday if needed.
     
  3. Tap

    Tap i hate it when a velociraptor throws poop at me

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    Looks like an old --HR.
     
  4. Texas-Tech

    Texas-Tech Official Geezer*

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    duhh
    Good job Otto
     
  5. Mcool

    Mcool Pipe layer

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    TN.
    Not such easy stuff there.I sure could'nt rewire with no diagram. Well done sir. But, the most important thing.........you trash the old parts or leave them on site .?:joy:
     
  6. Mcool

    Mcool Pipe layer

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    TN.
    Just kidding around Otto.I know you are a skilled mechanic.that dont leave any trash lol
     
  7. otto

    otto Bakery Chef

    Messages:
    19,866
    Location:
    in a van down by the river
    The old control is sitting next to the chiller, probably take them out when I'm done with all 3 chillers. I had a wiring diagram, I'll get a picture of that on Monday.
     
  8. jrbenny

    jrbenny Yuge member

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    31,370
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    Not here but over there.
    Nice work, otto
     
  9. Catpower

    Catpower The Crowd Pleaser

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    I used to hate those step controllers, well only when they ****ed up, they worked pretty good, but electronics sure make it easier

    Some of the HR's that size had 14 steps in it
     
  10. otto

    otto Bakery Chef

    Messages:
    19,866
    Location:
    in a van down by the river
    The first one I removed had 10 but, they were only using 8 of them.
    One of those controllers is going on the wall in my garage.
     
  11. HMD

    HMD does it matter?

    Messages:
    93,375
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    here
    dont throw out the 2nd...................
     
  12. otto

    otto Bakery Chef

    Messages:
    19,866
    Location:
    in a van down by the river
    I can hang onto one for the carage.
     
    mike1020 likes this.
  13. otto

    otto Bakery Chef

    Messages:
    19,866
    Location:
    in a van down by the river
    Here's some shots of the original diagrams. Did another chiller today and one more tomorrow.
    I am now running the two that are on the T775 controls at 47° setpoint, 5° throttle range and integral is back to the original 400 seconds.
    If someone can explain the integral adjustment in simple terms that would be great.
    P8120001.JPG P8120002.JPG P8120005.JPG P8120006.JPG
     
  14. otto

    otto Bakery Chef

    Messages:
    19,866
    Location:
    in a van down by the river
    So we're maintaining the 47° coming into the chillers, this is the reference, this is the way it was and this is the way it shall stay.
    When I asked why you can't reference the discharge, I was told "because that's the way it is".....still curious.
    Back to the settings: We're set 47°, compressor comes on at 48°, runs down to 46° or on a longer run, maybe turns off still at 47°.
    I guess this is the PID loop doing what it does. Not as cut & dried as a set of relays. The building engineer doesn't care about the return temp, just as long as the supply header from all 3 chillers stays between 47° and 44°. 48's too warm and 43's too cold. So far he's happy and if he's happy, I'm happy, Gino's Happy, You're all Happy we're all just a bunch of happy people. :lachen:
     
    jpb2 likes this.
  15. Tap

    Tap i hate it when a velociraptor throws poop at me

    Messages:
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    I could be wrong and it wouldn't be the first time but I believe its how fast or how tight your signl or relays stage. Like responce time. Should be in here.

    http://www.kele.com/Catalog/22%20Th.../PDFs/T775L%20Installation%20Instructions.pdf
     
  16. otto

    otto Bakery Chef

    Messages:
    19,866
    Location:
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    bad link. I read the install instructions on the Honeywell T775L (that's what we installed) still not 100% clear. Found lots of info on the integral adjustment od a PID loop online this weekend but, nothing that didn't give me a brain cramp.
     
  17. cd710f

    cd710f New Member

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    2
    hi! im doing one now im using t775l on the three comp hr chiller(1 and 2 comp are togather and 3 has its on circuit) in the programming will set it up for 2 loops? also 120 im using went to old step controller and it shuts power off to t775l when flow switch is open or chiller not being called for
     
  18. otto

    otto Bakery Chef

    Messages:
    19,866
    Location:
    in a van down by the river
    I would go single loop. If the old control had more than 4 relays, and it probably did, then you need an expansion module.
     
  19. Dowadudda

    Dowadudda Staff Member

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    6,223
    Location:
    Motor Room
    Emerson Retail Solutions / CPC e2E controller would work very well with that, and with just a bit of homework you could actually install, program and service this control system yourself. Remote access through either land line or IP, is very easy and user friendly, very intuitve system.
     
  20. crackertech

    crackertech assholiness *

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    And if you can do it anyone can.:D