I am currently switching a customer from a cast iron boiler to a wall hung tankless. Anyway I have traced the wire several times and there is no problem with the wiring. I can jump the r and w and kick the unit on. When I pop the face of the nest on the unit fires even though the nest is off. I have r,w,and c ran to the nest. Why am I having this issue?
Thanks for reaching out here in the Google Nest Community.
I'd like to further check on what's going on by getting a photo of your current wiring configuration to the Nest Thermostat. Is it still doing the same thing even if you remove the Nest Thermostat display from the base?
Thanks for being here in the Google Nest Community.
I'd like to bump in here and make sure that you’ve seen our response.
Please let us know if you have any other questions or concerns as I will be locking this thread in 24 hours.
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