Nest learning thermostat stopped turning the boiler on

[gregleleu]

Hi,

I have a nest learning thermostat which has been working ok* for a year and a half, and suddenly stopped turning the boiler on. The boiler is fine, I tried alternative wirings. Nothing works. The nest "looks" fine: turns orange when setting the temperature higher than the current temp etc.

Any ideas? I'm pretty sure it's an issue with the Nest itself.
Thanks!!

(*) Temperature control was fine, WiFi connected according to the nest, but "offline" from the app most of the time.

More details:

• Boiler-only system
• 2 wires R and W coming from the boiler (connected to Rh and W)
• External 24V transformer connected to C and Rc
• The boiler is works fine: twisting the R and W together turns it on fine
• Tried switching R with W and the two wires from the external transformer
• The transformer on the boiler and the external transformer are out of phase (but nothing I can do about it)
• Thought about trying the Nest Power Connector, but my setup worked before, so I don't see why I would need it now.

[Jhonleanmel]

Hi gregleleu,

Thanks for reaching out and sorry for the delay. I'd love to know more about this. Could you share a photo of your current thermostat's wiring? 

Thanks,
Mel

[Jhonleanmel]

Hey gregleleu,

Checking back in should you still have some questions here. Let us know by replying to this thread. 

Best, 
Mel

[Dan_A]

Hey there,

We haven't heard from you in a while so we'll be locking this thread if there is no update within 24 hours. If you need assistance or want to discuss topics, feel free to start a new thread.

Best,

Dan