Thermostat off but heating coming on

[SJT22]

I have had Nest Thermostat installed and working fine for the last 5 years. However in the last two days the heating has been coming on downstairs despite the thermostat set low (so should not be heating) or when I have manually turned it off completely. The radiators are still coming on despite the thermostat showing that it is off.

I have two thermostats in the house - one for upstairs and one for downstairs. The upstairs is fine and no radiators or heating is on as should be the case. My hot water is also working correctly. It is just the downstairs where there is a problem with radiators coming on when they should not be. 

There is no error message on the downstairs thermostat. I checked the energy history on the app and it shows no usage for the last week or so but I know that the heating has been coming on. So there is a problem. 

How do I fix it please? Many thanks!

[Sandra99]

I have exactly the same issue and the heating is on even when the heating mode is set to off.

I have noticed an icon that I don’t recognise (a black flame in a yellow circle) that seems to appear on the thermostat at the same time

Id be very interested to find a solution to this also

[SJT22]

I don't see that icon on mine. What I think could be happening for me is that the heating is coming on and going off as per the hot water schedule as it is now off as the hot water is off.

[Markjosephp]

Hello folks,

Thank you for taking the time to let us know about your inquiry. I'd love to know more about this.

Could you please tell us which Nest Thermostat model you have? From what country are you posting? Also, could you provide a rundown of all the steps you've tried?

Regards,
Mark

[EmersonB]

Hello everyone,

@SJT22 and @Sandra99, I'm dropping by to ensure that everything is covered here. How's it going with your Nest Thermostat? We would appreciate it if you could share the information we’re asking above. So that we could take a closer look and assist you further.

I appreciate the help, Mark.
 
Best,
Emerson

[Sandra99]

Hi,

I have 3rd gen learning thermostat and based in the UK

i think I have resolved my issue by disabling bacteria prevention. It was disabled a week ago and I haven’t noticed the boiler coming on since so hopefully that was the solution 

[SJT22]

I have been in Italy this past week, return in a couple of days time so will update then. Was still experiencing the issue just prior to going away so it’s not been resolved. 

[UanaC]

Hello there, @SJT22 and @Sandra99 ! I'm so sorry to hear about your issues encountered with your Nest Thermostat. 

@SJT22 can you please go into your Nest App, select the thermostat and at the bottom right side of your screen you should have History. Please press on the orange part where you know that the heating activated unexpectedly and if you can take a photo of it and attach it here would help a lot. 

@Sandra99 the icon you are seeing on your thermostat is the one representing the Bacteria Prevention feature. If you want to know more about this future you can follow this link: https://goo.gle/3WWWCbu. Please go to Settings -> Equipment -> Bacteria Prevention and click on Disable. Please let me know if this helped.

Many thanks, O

ana.

[UanaC]

Hello there! Just checking in with you. Did you see my message from above?

[UanaC]

Hey there, I haven't heard from you in a while so I'll be locking this thread. If you have any new issues, updates or just a discussion topic, feel free to start a new thread in the community. Thanks, Oana.