Nest Thermostat- What Am I Doing Wrong?!

[tb4122]

We have a Nest learning thermostat for our new central heating (we had useless night storage heaters before). Last night was the first time we've put the heating on and the Nest appears to be doing whatever the hell it wants!

I turned off learning mode so I could programme it to come on at 5pm if the temperature was under 18. Then I found it wasn't possible to set it to go off at a certain time, so I set it to the lowest (9 degrees) at 10:30. We went for a walk at lunchtime and came back to the heating on trying to heat to 18 degrees at 1pm and I have no idea why.

So now I've manually switched it off to stop it from switching on when it shouldn't and costing us money. Feels like it defeats the object somewhat to have to switch it on and off manually to prevent it randomly firing up the heating when I don't want it to. So far I'm really not liking it but DH loves a Google gadget so that's why we've got one... not that he can work out what it's playing at either

You can set it for lower than 9. You or the fitter have chosen that as either the safety temp which you cannot go below or the eco temperature.

Go into whatever you have called the thermostat. Then settings top right, the scroll down to eco and safety temperature and lower them. Now when you are setting the day to day schedule you will be able to turn it off by setting a really low temperature

That's what I thought but I've set the eco and the safety to the lowest (4.5 degrees and 2 degrees) and can still only set the temperature to 9 degrees on the schedule.

Took me ages to figure out my Nest. I’ve finally got the hang of it and set the heating to 18 degrees between set times morning and evening, and water in at set times. If I fancy a heating boost I turn it up manually. Learning mode off - what a waste of energy that was!

Are you sure it’s the heating that came on and not the hot water? Because there’s a default setting that will turn the hot water on to stop bacteria or something growing in your hot water tank. You can only turn the feature off on your thermostat, not on the app. See here -

support.google.com/googlenest/answer/9256656?hl=en-GB#zippy=%2Cturn-bacteria-prevention-on-or-off

Also check if your safety temperature is set where you want it to be as that will make your heating kick in to prevent frozen pipes. I have mine on 5 degrees but I think the default is higher.

I leave mine with heat off all the time basically just have it set to come on about 30 mins before we come home and it comes on again at 5am as my baby kept waking around 5.30 and I think it was cus she was cold seems to have sorted the problem!

when we first got it sometimes I’d wake up in the middle of the night sweating as the heat was blasting 🙈

So glad I found this thread. We've just fitted a Nest and it seems to have decided to come on at 5pm in the evening for two hours - that's it! I can't work out how to just switch it on in the day so we've been chilly. Ours is connected to an oil combi boiler, not sure if that makes a difference?

I've just discovered I can turn the heating on manually by pressing the button on the heat link (in case anyone else is looking for a way to override the thermostat).

My heating just came on randomly despite it not being particularly cold (for once). I turned it off on the app 5 minutes ago. Could still hear my boiler working, checked the app - still saying off. So I got up and checked the thermostat - which was showing as heating. I hate it.

What does this actually mean? I just turned up the thermostat a little. It is orange but there is no heating coming on. Is it 2 hr + until it will come on? Or is it telling me it will take the room 2 hr + to heat up? Does it make a difference if I also have a schedule set?

I've found mine really easy to use! Are you all using the app to set your schedules? Much easier than doing anything on the unit itself. Mine is set to 18 degrees for an hour each morning before we wake up then goes to 13 for the day since noone is home then 18 again from 4pm till bed. Usually heats up fairly quickly so ends up being on for 2 hours a day on average at the moment. Also have hot water on for a bit in morning and evening.

@LadyEggs that means the room temperature will be 20.5 in over 2 hours. At the moment it’s 18.5 degrees in your room.

@LadyEggs btw if it’s orange that means your heating is turned on.

If your heating hasn’t actually come on, it could mean there’s a problem with the boiler e.g. low pressure or a fault.

Di you hear your boiler start up when your heating turns on? My boiler is in my lift but I still hear it fire up if I’m upstairs when it turns on. Have a listen to what your system is doing - has the boiler turned on, can you hear your radiators firing up?

Typos sorry! I don’t have a lift 😂

Do you hear your boiler start up when your heating turns on? My boiler is in my loft…

On the app go to schedule pick a day and tap somewhere on the grid - drag the little dot up or down to select the temp and left to right to pick a time. You can place as many dots as you like so 18 degrees at 7.00 am and then 15 at 8.00. Then 19 at 7.00 pm then 13 degrees at 10.00pm. If you set the true radiant to 1 hour then it shouldn’t start preheating any earlier than 6.00 am for the 7.00 am desired temp. If it’s really cold through the night however the heating will come on but may not reach 18 degrees by 7.00 am. I currently have heating set for 18 degrees all day starting at 7.00 am and it just comes on sporadically for 20 mins or so a few times a day to maintain that temp. In the evening I turn it up a bit if too cold then it goes to 15 at 10 pm and doesn’t go on through the night at all. Average usage is 2.5-3.5 hours a day at the moment.

I thought that was a strange place to put a boiler

There has to be something wrong somewhere. Orange definitely doesn't mean the heating is on. It does sometimes. I think it has to do with the type of boiler we have (it's an oil combi) so I'm going to get our plumber back out. He fitted it so should know what's what. I imagine if it is working well it would be very good.

Orange definitely does mean the heating is on...

I turn off all learning and preheat settings. Then just set the schedule you want on one day, then you can copy and paste it to all the other days. We have it 18 from 10pm to 7am then 19 during the day. Then it will simply come on when the temperature is under what you want, and turn off once it hits the temperature. Easy. And you can just turn the temperature up manually if you ever want to override it - just put the target temperature higher than the existing temperature and the heating will come on accordingly.

Ooo how do you do this?

Settings (top right) - True Radiant - On - slide the slide to one hour (5 hours is the default) You could turn it off totally but it is quite helpful to just have the one hour to smooth out the effects of cold nights and warmer nights etc

I had no idea there were settings like that @ReedOfFate! thank you!!

I really like our Nest. Learning mode drove my DH mad so we disabled that, but it’s so much easier to control than our old thermostat. We are in most of the time, but if we pop out it automatically turns the heat down and then turns it up once we’re near home. I think it must save quite a bit of energy that way.

I love that I can control it from my phone. That really is so handy! And from Alexa when I’m feeling super lazy.

Our heatlink has died so currently have no heating at all!!

@allthecrooksandnannies what boiler do you have?

Our one did the pre heat thing. It kept on coming on at 4am as we'd set it to come on at 5:30. Dh wouldn't believe me for weeks as it would wake me up but not him. I had to Google it for ages to work out how to stop it.

@Droven it’s an Ideal but not sure which model!

I love my Nest, but it took a bit of getting used to. As others have said, turn down true radiant if you find the heating is coming on too early (I have ours set to an hour - the preset is 5). I also find the learning mode is useful; eg if you have the heating set to reach 18.5 at 8am, if you then manually turn the temperature down to 18 at 9.30am for a couple of days running, you should find that the thermostat then “learns” the pattern and builds it into the schedule. But equally you can set this manually via the app (go to schedule and then enter the min temperature you’d like it to sit at during the day).

I would also say that if you have a new Nest it will take several weeks to adjust to your home and boiler. We have recently got a new boiler which is way more efficient than the old one, and it’s taken the thermostat a few weeks to realise that the boiler heats the house much more quickly than the old one.

I inherited the thermostat with the house and was a bit cynical to start with, but it’s so useful and has definitely saved us money. We are in and out but not to a set schedule and I find it’s clever at switching to Away (our thermostat is in a high traffic area of the house). And what’s not to love about being able to switch the heating on remotely when you’re travelling home so you return to a toasty house?