topic Re: Nest Thermostat Won't Turn Off Heating in Nest Thermostats

Nest Thermostat Won't Turn Off Heating

Spenc91 — Tue, 09 Nov 2021 09:05:30 GMT

Hi,

I have had Nest Learning Thermostat in my house since 2017 and has worked great with no issues until a few weeks ago whereby the heating would turn on but when it reached the set temp it didn't turn the Boiler off so the house continued heat. After checking all the wires were still seating correct (which they were), i factory reset the Thermostat which didn't resolve the issue. I then changed the Equipment from Combi Boiler to System Boiler and the boiler instantly turned off. The App the was missing the feature to turn the heating on but that wasn't a massive issue as I was still able to turn the heating off and back on via the Thermostat.

Fast forward to this morning (09/11/2021) the heating came on as Scheduled however when it reached the set Temp it didn't turn off again. the only way for me to turn the heating off is to cut all power to the boiler. This happen as i was leaving the house for work so i was not been able to play around with the settings (i plan to tonight) to see if switching it back to Combi Boiler would work.

Has anyone else had the issue recently and know a Fix?

thanks in Advance

Re: Nest Thermostat Won't Turn Off Heating

ajp2001 — Tue, 09 Nov 2021 12:31:59 GMT

This has happened to us in the last couple of days , the heat doesn’t seem to stay on at say 20c as programmed but will definitely stay constantly warm . I have also noticed that our water isn’t getting as hot out of the taps as normal ? As it happens we have a British Gas service on Friday so we will see I suppose

Re: Nest Thermostat Won't Turn Off Heating

Spenc91 — Tue, 09 Nov 2021 18:34:40 GMT

I have the opposite issue where the heating doesn’t turn off!

Re: Nest Thermostat Won't Turn Off Heating

inHen — Wed, 10 Nov 2021 20:58:57 GMT

Same with ours. It only started doing it recently but it’s done it a couple of times over night and we’ve been woken up sweating and had to switch the whole heating system off at the circuit breaker.

There doesn’t seem to be a pattern of circumstances as it’s done it from preheating in the morning and my wife has just told me that she came home for lunch last week and the thermostat was set to 18*c but the house was over 25*c!

Perhaps a recent software update is to blame although I would have expected Nest to put out a bulletin and schedule for remedying the fault. It’s cost us about £48 extra in electricity bills as we’re an all electric household.

I haven’t seen any responses from Nest on the issue yet.

Re: Nest Thermostat Won't Turn Off Heating

Spenc91 — Thu, 11 Nov 2021 16:25:08 GMT

Yes! This is exactly the same we have! Nest Support advises I get a tech out to do a continuity Test on the heat link

Re: Nest Thermostat Won't Turn Off Heating

inHen — Thu, 11 Nov 2021 17:55:23 GMT

I’m an electrician and I can confirm that you don’t need a “tech” to check the continuity of your heat link because your heating wouldn’t switch on without continuity because it wouldn’t switch on at all without.

I’m certain it’s a software problem because the heat link isn’t cutting the run signal. It’s not a momentary signal to run and a momentary signal to stop its on or off.

Re: Nest Thermostat Won't Turn Off Heating

Spenc91 — Thu, 11 Nov 2021 19:17:17 GMT

Thanks for the info. I to didn’t believe them as all the checks we carried out over the webchat seem to be working fine so I spent the last two hours googling. Please note, I have no knowledge on heating/plumbing/electrical, it’s all shelf taught so if the bellow seems a lot of rubbish then it might just be but Here is what I found and seen to resolve my issue for now.

i noticed when the Nest thermostat reached the set temperature, it signalled the heat link to turn off the central heating switch valve (Myson power extra) but I couldn’t hear the valve close. After banging this with a screw driver it shut and the heating/ CH pump shut off. It’s now working as it should so I wonder when/if the central heating “valve” get stuck open then the boiler/CH pump stays on. When I turn on / off the heating now I can hear the value open / close.

Re: Nest Thermostat Won't Turn Off Heating

Noggie — Fri, 10 Dec 2021 22:10:42 GMT

I’m having this issue right now, was working fine and now the heating won’t turn off. Thermostat and app set to 15C, house at 22C and boiler still on. Wasting so much oil. We’ll try this combi thing

Re: Nest Thermostat Won't Turn Off Heating

Ctrot — Fri, 10 Dec 2021 23:17:10 GMT

I am having the same issue. Really disappointed. Sounds like a software issue that has not been resolved.

Re: Nest Thermostat Won't Turn Off Heating

Spenc91 — Sat, 11 Dec 2021 06:47:28 GMT

Hi Noggie,

My issue was due to the central heating value getting stuck open. Once I got this fixed, the heating as been fine

Re: Nest Thermostat Won't Turn Off Heating

ryancohen — Fri, 31 Dec 2021 00:33:55 GMT

I am having a similar issue.... I turned the Heat complete off on the Nest. However, when putting my hand on the forced hot water pipes, it is still relatively hot. Its about 36 degrees right now, and I have had the heat turned off for hours, and the house is still maintaining warm temp....

Re: Nest Thermostat Won't Turn Off Heating

Isadisa — Mon, 03 Jan 2022 11:36:37 GMT

We have also been having this issue for a couple of weeks. I did all the trouble-shoiting stuff. Reset everything etc.. It co tinues to blow hot air even when in the off position or on cool. I know nothing about hvac and I need to get this heat off before I melt. S.O.S.

Re: Nest Thermostat Won't Turn Off Heating

yardax — Fri, 07 Jan 2022 07:44:01 GMT

Im having this issue too. But ive discovered with my heater if i use the app to turn the hot water on and then off again straight away, then the heating turns off.

Re: Nest Thermostat Won't Turn Off Heating

DL1221 — Wed, 12 Jan 2022 17:01:07 GMT

Has anyone found anything on this? Having this issue here, too.

Re: Nest Thermostat Won't Turn Off Heating

RayC — Thu, 13 Jan 2022 11:53:25 GMT

I posted a similar problem yesterday.

Re: Nest Thermostat Won't Turn Off Heating

RayC — Thu, 13 Jan 2022 12:01:10 GMT

I spent a couple of hours on a Google Nest chat repeating the problem to be told that I should get Heat Link continuity wiring checked by electrician (why, if it is firing?) and then plumber to check valves. It took a long time to explain over and over the obvious issue, but I had to check history which did not record that the boiler was firing when in fact it went on heating at night until I manually had to switch off the system. So it is thought that it is not the controls at fault, but I am not yet convinced. Could it not be a failure of the Nest controls which are not doing what they display?

Re: Nest Thermostat Won't Turn Off Heating

DL1221 — Thu, 13 Jan 2022 12:42:46 GMT

Helpful, thanks. I also spent time on with google support yesterday. Similarly, had to explain the problem multiple times but eventually got a “level 3” tech who seemed to get it. My system, too, is showing as off even when the boiler is running, so the history tab is totally inaccurate. He was able to pull up reports looking at a variety of things and suspects it has to do with my system being only 2 wires. He thinks a C wire or a nest power connector would fix the problem. I’ve had my nest for a year and a half with no problem, so it’s not clear to me why this would happen and require that fix now, but he said it could be a variety of things, including the age of the boiler.

I am monitoring today and tomorrow to see if the issue persists before I do anything.

Re: Nest Thermostat Won't Turn Off Heating

RayC — Thu, 13 Jan 2022 14:25:31 GMT

Many thanks for responding. My issue has persisted for several days. I too wonder why it should suddenly need a different wiring when it has worked well since installation for a couple of years; something changed at the software end seems more likely or just total failure? Of course if Google Nest supplied a new thermostat that would be a great test, but although this used to be done quickly according to some YouTube advice, it has not been offered yet. Clearly I can only arrange to check out wiring with an electrician or use the plumber who originally fitted the whole system and is familiar with the set-up but fitted it as per instructions and does not claim to be a tech expert. This is not a quick fix.

Re: Nest Thermostat Won't Turn Off Heating

DL1221 — Thu, 13 Jan 2022 20:06:49 GMT

So far, I haven't seen the issue come up again today in my home. One of the troubleshooting steps the level 3 tech had me do was reverse my W1 and Rh wires -- he said it's perfectly safe to do so on a two-wire system like mine, and it might help us figure out what is going on. Not sure if that's a long-term fix, or just coincidental that, to date, we haven't had the issue occur again today. (And, for the record, not suggesting it would be a safe thing to do on your system without knowing your system! Proceed at your own risk!)

Re: Nest Thermostat Won't Turn Off Heating

RayC — Fri, 14 Jan 2022 11:08:47 GMT

My plumber solved it. Faulty motor spring mechanism on valve, so it stayed open even when told to shut off. Nest controls working fine, so spent longer than I should to get to that end. It seems to be a common problem and it would be good if Chat lines were able to suggest that sooner as a possibility.