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16 Sep 2019

Smart Thermostat Shopping Guide

By Lynn
  • Read time: 5 minutes
When purchasing a smart thermostat, it is important to check which thermostat best suits your needs and will work with your boiler or heating system. The experts from 50five have put together a short shopping guide, to assist you in choosing the best smart thermostat for your home.

Smart thermostats - the shopping guide

When purchasing a smart thermostat, it is important to check which thermostat best suits your needs and will work with your boiler or heating system. The experts from 50five have put together a short shopping guide, to assist you in choosing the best smart thermostat for your home.

To help guide you in your search for a smart thermostat, we have listed some functionalities and features of smart thermostats. We will explain what each element means and what it is suitable for. If you read through this page, you will learn what smart thermostats can do and be able to decide which thermostat will suit your needs. The first part of this page deals with which thermostats will fit your situation (depending on the type of central heating boiler, heating type, etc.).In the second part you can read about the different brands and types of smart thermostats.

Check which thermostat fits your needs

In this phase you can see which type of boiler you have, and which thermostats work with underfloor heating. Depending on your situation, you can choose from a certain number of smart thermostats. If you make the wrong choice, then it may be that your thermostat does not work properly.

1. Which thermostat works with my central heating boiler?

The first and perhaps the most important question that you have to ask yourself when choosing a smart thermostat. If you choose the wrong one, your thermostat will not work as it should.

There are two types of central heating boiler: On / Off and OpenTherm (also called modulating). An On / Off boiler will turn on if a room is too cold and goes off when the desired temperature has been reached. The disadvantage is that the boiler maximally heats and therefore also 're-heats' when the room is at temperature. This means a room can still be warmer than the desired temperature.

An OpenTherm (modulating) central heating boiler adjusts the flame to the heat demand. If, for example, the temperature only needs to rise a little, the heating is not fully switched on. The boiler keeps the water temperature at a stable level, making it also more energy-efficient than an On / Off boiler that continuously switches on and off.

Which thermostat should you choose?

Some thermostats work with both types of boilers, such as the Nest thermostat, Tado V3+ thermostat and the Honeywell Lyric. Other models come in two versions, such as the Honeywell Evohome OpenTherm and Honeywell Evohome On/Off. Still others only support one type of boiler, so pay close attention to which smart thermostat you choose.

Which thermostat suits your needs

If you know which smart thermostats you can install at your home, it is a matter of determining which functionalities you would like to see reflected in your smart thermostat.

2. Single zone or multi zone?

Do you want the thermostat to control the temperature throughout the house as one entire zone (single zone)? Or do you want to expand your smart thermostat with smart radiator valves , which you can set to heat multiple rooms / zones separately (Multi-zone)?

Multi-zone heating means that you put smart radiator valves (thermostatic radiator valves or TRVs) on the radiators, each of which can be controlled separately by the thermostat. For example, you can set your bathroom at 24 degrees, your living room at 20 and your bedroom at 18. It is advisable to put a TRV on each radiator if you choose multi-zone. Otherwise you may find that there’s a radiator on somewhere consuming unnecessary energy.

Which thermostat do you choose?

Multi-zone heating is only possible with thermostats that can be expanded with radiator controls. View all brands that support smart radiator valves.

3. Underfloor heating

Do you have underfloor heating and do you want it to be regulated by a smart thermostat? You can, but make sure that the thermostat can control underfloor heating. Although almost all smart thermostats can do this.

Which thermostat should you choose?

Do you also want to set your underfloor heating as a separate zone for a multi-zone heating solution? Then you can choose the Tado thermostat or the Honeywell Evohome thermostat.

4. Self-learning or not?

Self-learning means that the thermostat can 'learn'. There are two types: self-learning heating and self-learning programming. Self-learning warm-up means that the thermostat learns how long it takes for your home to warm up. Based on this, the thermostat will start to warm up your home either earlier or later, so that the house is at the right temperature when you come home. Self-learning programming goes a step further: the thermostat learns about your lifestyle and on that basis independently programs the times at which the heating is switched on. Very useful if you work at regular intervals and are out of your home at the same time every day. However, this function is of little use if you have irregular times that you are home, or if family members are home at irregular times.

Which thermostat should you choose?

Thermostats that are warm-up self-learning include the Tado thermostat and Honeywell Lyric T6. The Nest Learning thermostat is a thermostat that can also program self-learning.

5. Heating based on GPS location

Also called the geo-fencing or presence function. This feature means that your smart thermostat can 'see' whether you are at home using the GPS location via your phone. Based on your location, the heating is switched on or switched off. Leaving for work in the morning? Then the thermostat switches off when you leave. On your way home from work at the end of the day? Then the thermostat will turn on the heating while you are on the road.

This function ensures that you do not have to manually operate your thermostat. If each family member has downloaded the app, the thermostat will adjust the temperature down when the last family member leaves the house. First family member almost home? Then the temperature is turned up again.

Which thermostat should you choose?

Thermostats with geo-fencing: Nest Learning thermostat, Tado thermostat, Honeywell Lyric T6.

6. Wireless thermostat

In general, the smart thermostat replaces your old, wired thermostat. So this smart version will also be mounted on the wall and on the power network. However, there are thermostats that you can carry with you through the house.

Which thermostat do you choose?

Of course, all smart thermostats can be operated wirelessly via the corresponding app. The Honeywell Evohome, Honeywell Lyric T6R and the Tado can also be used wirelessly. If you want to use the Tado wirelessly, however, you will need the Tado Extension kit.

7. Linking with other smart home solutions

The choice for a smart thermostat also depends on the extent to which you want to incorporate it into a smart ecosystem in your home. It is possible to link your smart thermostat to smart lighting and smart security.

For example, you can instruct the Nest thermostat to turn off the boiler when the Nest Protect CO alarm goes off. This prevents further spread of CO. Connect smart lighting to the thermostat to give a light signal when a boiler malfunction is detected or let the lights go off automatically when the thermostat no longer detects anyone in the living room.

Which thermostat should you choose?

There are various options for linking your smart thermostat to other smart home solutions.

For example, the Nest thermostat works with other Nest home smart home solutions, such as Nest IP cameras or Nest Protect smoke CO detectors. Philips Hue lighting also works with Nest products as standard. Check beforehand which thermostats can work together with other brands.

Another way to connect your smart thermostat to smart home solutions is by using IFTTT. This app can link smart home products and online services through specific conditions. An example: if it is outside colder than -10 ° C, set the thermostat to 22 ° C. Also check out which smart thermostats work with IFTTT and with which devices you can connect your smart thermostat.

8. Should you self-install or not?

Installing a smart thermostat is not easy and not for everyone. Especially with multi-zone solutions there is a lot more to it than simply replacing your thermostat for the smart version. Do you want to be sure that your smart heating solution works properly, and you get the most out of your smart thermostat? Have your smart thermostat installed by smart home experts at 50five!

We offer various smart thermostats that can be installed by one of our smart home experts.


Written by Lynn

Writes blogs about EV charging and climate solutions for 50five.