Thermostat clicks but nothing happens

Discussion in 'HVAC' started by o2284200, Sep 16, 2016.

  1. Dec 21, 2016 #41

    kok328

    kok328

    kok328

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    Nothing in this diagram, it's very basic. Are there any others on the unit?
     
  2. Dec 21, 2016 #42

    kok328

    kok328

    kok328

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    BE CAREFUL!!
    Turn power on to unit.
    Put your volt meter leads on L1 & L2 on the TBI in your diagram.
    240Volts?
    Now put your leads on the orange and black wires leading to the CT control transformer.
    Still 240Volts?
    Now put your leads on the brown and read wires on the CT.
    24Volts?
     
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  3. Mar 1, 2017 #43

    o2284200

    o2284200

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    Thanks!
    A bit confused and preparing to call ac tech but here's what I checked:

    1) Pulled purple fuse partially out, just enough so that I can get my multi meter probe to make contact with the "blade" on the fuse.
    READINGS:
    Touched the red probe to one side of the fuse and got no reading: 0.
    Touched the red probe to the other side of the fuse and got no reading: 0.
    [​IMG]

    2) Checked for 24vac, as follows....
    Power on...Meter to 200vac...The probes fit in bottom of top terminals (red and brown), where arrows were added to pic...
    NO READING: 0

    3) Checked for 240vac, as follows....
    Power off...Slid the bottom terminals (orange and black) down slightly to expose the metal blades of the transformer.
    Power on...Meter to 750vac...Placed one probe on orange and the other on black...
    READING: As high as 4 (four).
    [​IMG]
     
  4. Mar 8, 2017 #44

    o2284200

    o2284200

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    OK, I bit the bullet and called in a tech for a service call. He came out and first checked the thermostat and then went right for the breaker inside the air handler, at top...Power coming in...No power going out. Then he went outside to the condenser and found a wire burnt out, at the top.
    $89 for diagnostics OR $350 for repair (replace breaker & repair top of wire).
    What would you do?
    [​IMG]

    [​IMG]
     
  5. Mar 8, 2017 #45

    o2284200

    o2284200

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    I replaced the breaker ($59 at local electric supply store) and repaired the wire, in the condenser, as recommended...I now have a/c! [​IMG] Total out of pocket $123 ($64 diagnostics + $59 breaker) vs. quote of $350 = SAVINGS of $227! Thanks to all, who helped along the way! [​IMG]
     
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  6. Mar 9, 2017 #46

    WyrTwister

    WyrTwister

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    The 2nd photo looks like a contactor ?

    Glad you got it repaired . :-_)

    God bless
    Wyr
     
  7. Mar 9, 2017 #47

    slownsteady

    slownsteady

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    I would be watching that wire. If the cause of the burn out wasn't corrected, it could happen again.
     
  8. Mar 10, 2017 #48

    WyrTwister

    WyrTwister

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    Strip back enough insulation to expose shiny copper . Clean / wire brush the screw / contact point . Tighten securely .

    Often caused by insufficient " tightness " or vibration loosening the fastener .

    God bless
    Wyr
     
  9. Mar 26, 2017 #49

    o2284200

    o2284200

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    Thanks!
    Definitely, will keep an eye on, in future, now that I know. One issue, if it happens again is, I won't have enough wire to reach contact.
     
  10. Mar 27, 2017 #50

    nealtw

    nealtw

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    I think inside there you can just add a pigtail.
     
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