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How to replace a transformer on a Taco SR 504

Transformer just went on a Taco SR 504 switching relay. Looks like it's soldered and bolted in. I'm surprised the fuse didn't blow first. Do I get my solder gun out and gently release the wires then unbolt? Any help would be appreciated.



  • Tim McElwain
    Tim McElwain Member Posts: 4,445
    Replace the Taco SR 504

    but first find out what caused the transformer to go.


    mount an external Honeywell AT150F circuit breaker transformer and after disconnecting the wires from the SR 504 transformer connect it up. The circuit breaker will prevent burning out another transformer just in case you have a short. Just leave the old transformer in the SR 504.
  • Matt_Connolly
    Matt_Connolly Member Posts: 14
    Thanks Tim

    Worked fine. Turns out it was easier to remove the old transformer off the circuit board. I soldered leads to the new transformer.
  • icesailor
    icesailor Member Posts: 7,265
    Replacing Transformers:

    Remember, not everyone can do what you did.

    For most of us, we don't carry electrical soldering tools and the matching transformer in our trucks. The "Run Around Time" will eat up the labor to just get a new one and replace it. Unless you do what Tim suggested, an external transformer with a circuit breaker. And you still might end up replacing the control.

    The isolated place I worked, would have the replacement control. On the shelf. A transformer would be a special order. $50.00 air freight and you usually didn't get it the next day. Next day Fed-Ex was always 2 days. UPS could be a week.

    And then it could be the wrong transformer because no one listens to what you tell them.
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