Garage 2 wire heater. No C wire terminal. Nest Power Connector not working

Gnon17 — Wed, 04 Oct 2023 12:48:03 GMT

I have a natural gas heat only system in my garage. It’s two wire (R &W) with no C terminal at the heater controller. After installing the Nest, I was informed that I needed a nest power connector. I bought that and since I have no C wire terminal, I was instructed to buy a 24v transformer. I installed the transformer and connected the nest power connector as instructed. However, now my nest is saying the R and W wires aren’t detected, but the C wire is detected and it’s receiving power. I’m wired exactly like it says in the attached instructions, and I also removed the jumper from the connector, as instructed. The only possible thing I can think of, is that it looks like my R&W wires that originally ran to the old thermostat were connected to another transformer. Where the W wire comes from one transformer terminal and the R wire comes from a controller board. The other side of the transformer also connects to the controller. I attached my current wiring and the instructions page I’m using.

Re: Garage 2 wire heater. No C wire terminal. Neat Power Connector not working

RenzJ — Sun, 08 Oct 2023 17:34:38 GMT

Hi Gnon17,

Thanks for posting here in the Google Nest Community forum. We'd be happy to take a look into this for you. Please answer the following:

What type of Nest Thermostat do you have?
Send us the current wiring of your Nest Thermostat.
Send us a photo of the control board wiring.

I look forward to your response.

Best,
Renz

topic Garage 2 wire heater. No C wire terminal. Nest Power Connector not working in Nest Thermostats

Garage 2 wire heater. No C wire terminal. Nest Power Connector not working

Re: Garage 2 wire heater. No C wire terminal. Neat Power Connector not working