Smart Thermostats – How to save money and use less energy

salus main

Salus iT500 main unit

Smart Thermostats are a great way to control and monitor your home’s heating. This article is all about introducing you to them and highlighting  how they can save you money and reduce your energy consumption.





What are Smart Thermostats?

A smart thermostat is like a thermometer with a built in sensor and on/off switch. You set the thermostat to say 21 degrees and if the air around the thermostat goes below that it will wirelessly  tell the boiler to heat up the water and moderate the temperature of the whole house to match that room. Once it reaches 21 degrees the boiler stops heating.

If the above wasn’t smart enough; imagine being able to control the heating on your way back home using your smart phone – this is what the latest range of smart thermostats help you to achieve. 

Why buy a smart thermostat?


Tado’s remote control of a boiler

What’s the most expensive bit of technology in your home? Apple iPhone, Ultrabook laptop, Audio system? Turns out for most homes the most expensive bit of kit is the boiler – in fact a new, energy-efficient boiler will probably set you back £1,100-£2,500 including installation.

What if there is still life in your boiler and you don’t want to spend thousands upgrading it? If your boiler isn’t that old and is still going strong, a cheaper way to make your boiler more efficient is to make it smarter is by adding a smart thermostat to it. There is a growing list of smart thermostats and systems appearing on the market, all of which promise to slash your heating bills.

In our home we have been using an entry level smart thermostat called the Salus IT500 and connected to our 15 year old energy inefficient boiler and already in 12 months we have saved over £200 on our heating bill. The cost of the device was only £139 from Amazon and we paid an electrician to wire it to the boiler costing us £50. so its already paid for itself.


Why replace traditional thermostats with smart ones?

Thermostats have been around for a while now just without the ability to remotely manage them away from home. Often they are placed in corridors which don’t have radiators so the boiler keeps using fuel to heat the house. All the rooms get very hot and the hallway stays cold; the net result being that you use and pay for a lot of fuel.

Heating using traditional thermostats is geared towards the whole house and not individual rooms which means you end up using more fuel to heat a larger area. To manage individual rooms you have to manually adjust the radiators in each room which is tedious.


Salus iT5000 starter thermostat kit

How Smart thermostats work

A receiver unit is wired to the boiler and its primary role is to communicate wirelessly between the boiler and the smart thermostat.

The smart thermostat is a wireless unit the size of an average phone and can be moved around the home. Usually they can be wall mounted or have a stand to sit neatly on your coffee table.

The idea is that you take the thermostat with you wherever you are in the home. For example I work in the dining room during the day and the lounge in the evening. Once I am in that room, I close the door and set the temperature I want – the thermostat then communicates with the receiver unit which in turns tells the boiler to burn gas and heat the room.

The thermostat has an inbuilt thermometer and once it reaches the desired temperature it tells the boiler to stop burning gas.

As the thermostat is monitoring temperatures locally in a room; this means that only a small area can be quickly warmed to the desired temperature and then the boiler can stop heating and using fuel.

All smart thermostats let you program temperatures for certain times of the day including specific on/off times during weekdays, weekends and holidays so you can lower the temperature automatically when you are out of the house.

No more dials

Smart Thermostats have a room sensor which you can program on/off times and select desired temperatures. You can also do all this from your smart phone or via the manufacturer’s website.

The quality of both the smart thermostat and the smartphone app vary from sliding bars to a digital dial and in my opinion you pay more for the systems that have greater options and presentation in their apps and website. Whilst I am very happy with the Salus IT500 the apps and website controls are much more limited when  you compare it to the Tado, Nest and Hive systems.

Controlling your heating while away from home


Nest’s learning technology

We went away for a two week break last winter and I totally forgot to change the heating from the regular on twice a day setting on the thermostat to the “frost protection” mode so in case the temperature went below 5 degrees it would keep the pipes warm.

Under normal circumstances this would have left a very warm home heating nobody! However all I had to do was pull out my Android phone and enable the frost mode quickly while queuing at the airport.

The other reason to have remote control is when you are coming home early and want to arrive to a toasty warm home without having to wait for the heating to kick in. Simply pull out your iphone or android phone on the No58 bus and start up the boiler.



I am generalising here and there may be specifics relating to the type of boiler you have. Its always worth checking whether your boiler is compatible and if if you are in any doubt about the installation process get a professional in to do it for you.

There are three sides to the installation:

  1. Connecting the receiver unit to the boiler – recommend you get either a heating engineer or an electrician to do this
  2. Setting up the  smart thermostat and linking it to the receiver unit – you can do this or ask me to do it for you!
  3. Connecting the smart thermostat to the internet by plugging in the a hub/gateway to your router – you can do this too or ask me.

What else can they do?

Hot water too

If you don’t have a combi boiler then you will need to choose a smart thermostat that can also control your hot water in much the same way via a heating schedule and ad-hoc when you are away.

Automatic Scheduling

It doesn’t stop at heating,  some of the more specialised smart thermostats like Nest learn from your behaviour patterns by noticing when you change the temperature and create a schedule around that rather than you having to do the thinking.

Presence and location sensors

Using the GPS in your smartphone the high end thermostats realises you are away so turns off the heating and on the day you decide to stay at home, they senses your movement in the house and starts the heating – pop out for a coffee for an hour and it will gently lower the temperature to save money but raise it again as you approach home. If you’re out all day on a trip the heating will lower further and for longer, and  knows when to raise it again when you’re on your way home. All this is called GEO Fencing in case you were wondering!

Air Conditioning

If you are lucky enough to live in a hot climate then smart meters can do the opposite and control your air conditioning in exactly the same way it manages your boiler.

Carbon Monoxide and Smoke Detection

Others like Nest have specialist devices that monitor for carbon monoxide and act as a smoke dectector. Both are linked to your smart phone.

Boiler Monitoring

Its ok having a smart heating system if your boiler has a problem. So often failing water pressure can be a big issue for heating systems. Thankfully the more advanced systems have an inbuilt boiler monitoring sensors which alert you immediately.

What is the best Smart Thermostat?

All of them provide you with wireless heating which you can control. Its just whether you want to experience some of the “smarter” features like GEO fencing, motion detection and automatic programming plus have a better looking mobile and web app to control your thermostat.

The table below gives you a very high level overview of the main smart thermostats, a comparison of their features, how much they cost and where to buy them from:

Smart Thermostat Comparison Table

What about multi zoned smart heating systems?

I think we have done enough tech speak for this blog, however if you want the ultimate heating system that can control the temperature and program each room in your house separately then you may want to look at Multi Zoned heating systems – hopefully to be covered in a future blog!

About Carl the IT Hound

I am passionate about all things technical and in helping businesses to improve how they work and experience greater efficiencies with the right technology
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