Heat always on, Nest E thinks everything is fine

[lyndonhalfway]

My Nest E thinks that everything is hunky-dory even when the thermostat is set to 9 (at night), its own reading says the room temp is 21, and the boiler is still churning away. This started about a week ago. There's no alert about connection to the heat link, there's no alert about heat link having a low battery, all wiring is fine, no error codes anywhere, the thermostat just... is living in fantasy land, reporting that it's controlling the boiler but it's not. This is getting really expensive! Thoughts appreciated (since Google's troubleshooting section does not address this issue for Nest E!). 

[Paul_R]

Hi there! I'm really sorry to hear about it, but I'm here to help. Could you please activate and deactivate the heating from the app, and listen if the Heat Link makes a clicking sound when you do? I want to confirm if the Heat Link works properly, and then we'll see what we can do further.

[lyndonhalfway]

Hi Paul_R, we needed not to go bankrupt running the heat, so I had a boiler mechanic check it out (after resetting the Nest, re-doing the app, resetting the boiler itself, checking connections, all the things one would think to do) and he got it going again by spraying WD-40 in the connection ports of the heat link. Our theory is that the heat link must've got wet and the moisture in the ports was making the connection. Little alarming/surprising that the Nest didn't realise the boiler was on, but <shrug>. Thanks for reply, anyway.  

[Paul_R]

I'm always glad to assist! Is there anything else I might help you with?

[UanaC]

Hello there! Did you manage to see the message from above?

[lyndonhalfway]

Yep, and my reply to it is above. Thanks!

[UanaC]

Thank you! I'll close this thread for now. If anything comes up, feel free to open a new thread. Have a nice day and stay safe.