I have read for hours, and tried figure this out myself, but I need help. I'm trying to connect the Blue C wire from the tstat, without a C terminal at the furnace.

enter image description hereFrom what I have read, it seems to me that I would connect the C wire from the thermostat, to one of the 3 BL wires coming from the 24v transformer. If that is correct, I am still not sure which of the 3 BL wires to use.

Thanks in advance for any assistance!

  • 1
    All 3 are connected to the same point on the transformer. It shouldn't matter which one you use. – brhans Aug 24 '16 at 19:31

Yes, you'll connect to any of the blue wires coming from the transformer.

If there's an empty terminal on the transformer, connect there. If not, you might be able to use a piggyback spade connector.

enter image description here

Otherwise, connecting at the point of grounding would be the next easiest location.

enter image description here

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.