/ Home & Energy, Money

For and against smart thermostats

Cat on radiator

Smart thermostats are the latest trend in home heating. But do they really help to heat our homes more efficiently? Two Which? staffers put them to the test…

Lisa Barber says:

Lisa BarberYou might think that getting a smart thermostat – which controls your heating from an app on your phone – would cause your energy bills to rise. After all, surely it’s far too tempting to keep yourself cosy by turning up the heating from the comfort of your duvet or sofa?

However, I find I actually spend my time turning my heating down. As I haven’t got to fiddle with the overly complicated control panel on the old thermostat, I’m much more likely to keep on top of making sure we only use the heating when we really need it.

Plus, my smart thermostat lets me control individual radiators. This means that when I’m in front of the TV of an evening I can spend a minute switching off radiators in any rooms I’m not using.

Being able to see the temperature in individual rooms is rather handy, too. It’s much easier to demand that your family put jumpers on if you know it’s already over 20°C. Whereas with our old thermostat, which lived in our draughty hallway, we never really knew what the temperature was and whoever was coldest would usually sneakily turn up the dial.

So for me, having a smart thermostat has definitely reduced the amount of energy I use.

Amy Hupe says:

Amy HupeI was tempted into getting a smart thermostat – not so much to cut my energy bills, but because of the added convenience. That said, I was interested to see if greater control and feedback about my consumption would encourage me to use less – it has not.

I really feel the cold, always seeming to be several degrees chillier than everyone else in the room. The ability to switch my heating on when I leave work, so the house will be cosy as soon as I walk in the front door, has proved stronger than my desire to reduce my heating bills.

My other half and I both have the app installed on our phones, and when we first had our smart thermostat installed we set out with firm resolve to remember to switch our heating off when we went out for the day at the weekend (when our heating is set to 20°C by default).

Sadly though, with nothing to remind us, we only tend to remember about half the time – the same as when we had a standard thermostat. While I feel motivated to turn my heating on when I’m cold, there’s little to remind me to switch it off when I don’t need it.

All in all, while I think it’s been great for convenience, I’m just not as engaged with my energy use as I am with my comfort, and getting a smart thermostat hasn’t changed that.

What do you think of smart thermostats?

If you already have a smart thermostat, tell us more about it – particularly if it has smart learning, as we want to know more about whether this actually works. If you don’t have a smart thermostat, do you think one would work for you?

Disenchanted says:
8 November 2015

I purchased the Tado system in August and its still not working properly. I had a Climate system in my last home and that worked well – I like the ability to switch on my heating when I am returning from a trip. I changed to Tado as it does not have a yearly charge. The Tado was professionally installed but is connected to my computer and therefore is inactive when the computer is off. There should have been a lead with it to overcome this problem but I do not have it – repeated calls to Tado have resulted in other parts being sent but not the one I need. The installers would not come back as they are only paid for one visit. I’m on the point of uninstalling it.

I have a Nest thermostat. I work random hours and get up at different times morning, so switched the smart learning feature of straight away. What I like is the ability to program the start times for the week easily via the phone app.
I also find being able to alter house temperature remotely useful.
My wife works from home and sometimes stays in the study for a long time. Normally this would mean Nest would drop into “Auto away” mode as she hasn’t walked pass the movement-senses thermostat for a while. I got round this by installing a 3rd part app on her phone called “@home with Nest”. As long as her phone is connected to our home WiFi network ( i.e. she is at home too) Nest won’t drop into auto-away.

To be honest I don’t think these gadgets are worth the money.
If you have your system sensibly tuned with a wall thermostat and rad stats that’s as good as it really gets. But don’t put the wall thermostat in the hall put it in the room you want the warmest. Remember your wall stat is the overall control. Then each of the rad stats will allow heating on up to when the wall stat trips off.
About the only real use of remote phone control is if you’re at the airport and you forget to turn the heating off before going on a winter holiday. Doesn’t happen that often really does it?

I have had a tado smart thermostat control my heating and hot water for the last two years. It has been fantastic. I’m struggling to see how it gets such a low score in the review especially the criticism that it is low in features when it seems to have more than any of the others!! Firstly it has operated faultlessly. Original self installation was a breeze with the excellent customer service. I got sent detailed diagrams of my old analogue thermostat and exact step by step wiring diagram. I had a couple of queries and I got instant help over the phone. It’s always difficult to make before and after comparisons because heating is so weather dependent. I would say it is only about a 5-10% saving though. The biggest difference is that it is uncannily accurate and the temperature always seems to be exactly at the right temperature whatever is going on. It just makes minor adjustments all the time. It knows when one or both of us are out and turns the heating down to whatever our pre-set eco temperature is and turns it on as we approach home! How good is that? It learns smartly and takes into account the outside weather to know how aggressively to use the boiler. Again the Which? report seems flawed. Programming by phone or PC is simplicity itself and easy to manual override on these devices or just tapping the up or down button on the thermostat. It then stays like that till the next program kicks in or you cancel it. Not sure why you want to look at the temperature on the wall but you just press a button if you do. Did I mention you can just say to Alexa “turn heating up one degree” ? You can buy various add ons to control individual rooms but I don’t know how good they are.
The comment in the reviews about accuracy of temperature readings shows a complete lack of understanding of how we control our heating. We should be setting to our comfortable setting and it is completely irrelevant what the thermostat says that absolute reading is!
So I seem to be at variance with the reviewers and others but I guess it depends what you expect and want from it.