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Contractor on heat pump pulls out when disconnect plugged in?

Discussion in 'Residential' started by Rgtill31, Oct 23, 2017.

  1. Rgtill31

    Rgtill31 New Member

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    5
    Can anyone help me out, the unit was running when I got there, has like no freon in it and capacitor for compressor was very low like 30/50mfd, put new capacitor on and when I plugged in the plug for the heat pump the contractor pulls out losing 24 volts, the high side doesn't trip and when I unplug the disconnect the contractor pulls back in? Has anyone ever run into this, I've tried bout everything, I'm convinced compressor and fan are ok I checked them to ground, they are open so what is it? Gotta be something on 24v side outside right.....oh yeah there's no wire diagram for 24 volts side for this unit, unplugged 24v wire from defrost board to contractor, still pulls out
     
  2. coldsnap

    coldsnap -20 on the money

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    Wisconsin
    I pull out on some services I provide
     
  3. knave

    knave Undeterred

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    Out for a rip
    Low pressure safety?
     
  4. 404eh

    404eh New Member

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    It was running when u got there...
     
    Daryl_Dixon likes this.
  5. knave

    knave Undeterred

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    8,121
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    Out for a rip
    Maybe a time delay built into the board.
     
  6. Sdeery

    Sdeery Machinist in training

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    Armpit of the USA
    Wonder what the control voltage is and if the transformer is tapped properly.

    sdeery
     
  7. Rgtill31

    Rgtill31 New Member

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    Yeah maybe it was just a time delay huh? It was late and my brain was spent for the day guess I just never seen a contactor pull out like that and then pull back in when I plug in the disconnect.... Wouldn't it just not pull in at all, even with time delay or pressure switch?
     
  8. Rgtill31

    Rgtill31 New Member

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    5
    I measured control voltage is indeed 24v
     
  9. Zman

    Zman Hanging by a Thread

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    The "I know a Guy" State
    Replace the CONTRACTOR, with one that works correctly.
     
    doc havoc likes this.
  10. frozensolid

    frozensolid Psychologist's Dream

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    Sounds like a Ghost in the machine. You need an refrigeration exorcist. $$$
     
  11. Texas-Tech

    Texas-Tech Official Geezer*

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    17,598
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    duhh
    I’m confused, your saying the contactor is pulled in before the power is restored?
     
  12. jays 65

    jays 65 New Member

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    337
    gets power from air handler normally doesnt matter if disconnect is off on condensor
     
    Anita sannich likes this.
  13. Rather B Riding

    Rather B Riding Behind bars

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    552
    If it's a single pole contactor you could still have a bad motor or another electrical issue. Disconnect the fan motor and compressor from the contactor and get the contactor working right before rewire them back in. Some newer HP monitor high voltage too.
     
  14. Texas-Tech

    Texas-Tech Official Geezer*

    Messages:
    17,598
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    duhh
    Ok, guess I’m used to commercial equip, forgot about the 24 in the air handler
     
    Rather B Riding likes this.
  15. NZ All Blacks Fan

    NZ All Blacks Fan Just Another swinging Dick

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    9,384
    Location:
    West Coast - Canada
    3 1/2 year s I smell bull shit here you should be able to figure this out yourself if you have had any kind of training. ?
     
    Zman, Texas-Tech and 404eh like this.
  16. knave

    knave Undeterred

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    8,121
    Location:
    Out for a rip
    3.5 years of install helper and parts runner could result in this possibly
     
    Catpower and Zman like this.
  17. Rather B Riding

    Rather B Riding Behind bars

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    552
    I've seen guys in a lot longer that could not wire a heat pump. When I was doing residential I found heat pumps wired wrong all the time.
     
    Catpower likes this.
  18. 404eh

    404eh New Member

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    196
  19. crackertech

    crackertech assholiness *

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    Fl/IN/Ga/Ms/TX/NJ/VA/NC/TN

    Fixed :D
     
  20. Rather B Riding

    Rather B Riding Behind bars

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    552
    One kenobi