The thermostat is an important component of the boiler system, but what does it perform exactly? This article will go over the fundamentals before delving deeper into how boiler thermostats function. It will further elaborate on the many types available, and how they can be used for smart heating.


What Is A Boiler Thermostat?

What Is A Boiler Thermostat?

A thermostat is simply a switch in central heating. But, rather than a human, it is turned on/off by room temperature variations.  So, if you want to adjust your central heating and hot water temperature, you'll need a boiler thermostat.

In a home, the boiler is the primary source of heat. It can be a communal or household heating system component. It provides the heat required to maintain a pleasant household temperature, whether it operates on wood, oil, or gas. 

As a result, it consumes a significant portion of a household's budget. That is why it's advisable to invest in a thermostat, a heating control device or a Smart AC Control. It reduces the amount of energy consumed by a boiler and saves money.

Starter Kit – Smart Thermostat

Make your central or underfloor heating smart. Save energy and maximize comfort. Available in two versions: Wireless and Wired.

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How Does A Boiler Thermostat Work?

Your boiler performs two functions: 

  • providing hot water to your radiators 

  • providing hot water to your showers and faucets. 

It's only natural that you'd have separate temperature controllers for these two purposes. This is why a 'boiler thermostat' is two sub-thermostats together.

So, where do you find them, and how do you identify them? It is based on the kind of boiler you have.

What can a traditional boiler thermostat do?

A thermostat maintains the water temperature in your cylinder at a set level. It accomplishes this by heating the water if it falls below the thermostat's set temperature. Then, it shuts off the cylinder's heating to prevent it from becoming excessively hot.

It utilises a sensor to detect your home's temperature, and as a result, it keeps track of what your boiler is doing. The room thermostat detects that your house has achieved the desired temperature. This turns off the central heating system. It will restart the boiler again when the temperature lowers.

What Are The Types Of Boiler Thermostats?

Several boiler thermostats are available on the market for heating regulation equipment. They vary on a variety of costs, functions, and regulation levels. Some of them are:

Atmosphere thermostats

The purpose of an atmospheric thermostat is to control the temperature. It's equipped with a temperature sensor that monitors the room's temperature. Further, it compares the setpoint value you selected and informs the boiler when to start or stop operating. 

The environment thermostat directs the boiler to start up if the air temperature is below the setpoint temperature. Meanwhile, the atmosphere thermostat instructs the boiler to stop generating heat. It does that once achieving the set temperature. This implies that the room's temperature remains constant. Therefore, regardless of air movement and household activities, there will be no changes.

Programmable thermostats

Programmable thermostats are a more advanced type of boiler thermostat. A programmed thermostat adjusts the temperature by changing the boiler's operation. Like an atmosphere thermostat, it is based on the temperature in the house. It also allows you to customize the ambient temperature based on the time of day. 

You can program various setpoint temperatures for different periods of the day (daily programming). You can also manage it for days of the week using a programmable thermostat. The more advanced version, known as a smart thermostat, comes in a wireless programmable thermostat.

This allows you to keep your house at the required comfortable home temperature when you're at work. Also, it prevents having the heater on needlessly even though you're not there. Weekly programming allows you to change the program on specific days, such as weekends when you'll be at home for a longer period. You may also turn down the heat at night with a programmable thermostat.

Smart programmable thermostats

Smart programmable thermostats provide the same benefits as atmosphere thermostats and programmable thermostats. It helps to regulate and program temperature, while also upgrades and introduces new features. 

A smart thermostat allows you to select a very accurate setpoint temperature. It keeps your house pleasant without causing unwanted temperature changes. It is programmable. So, you can set different heating temperatures for various times of the day. And, you can customize the program for various days of the week with weekly programming.

For instance, tado° devices come with a tado˚app, allowing the user to control the temperature setting using an app remotely. You can change the temperature or control the temperature with the app. This can be an excellent step to a smart home integration.

In addition to regulating and programming, many boiler thermostats include additional features. For instance, the tado° smart radiator thermostat determines when to turn on the heating if needed. This regulates the insulation of your home and the external temperature. A smart thermostat can also alert you if it senses an issue with your boiler or if the device's batteries are about to run out.

The tado° radiator thermostat works with the most popular voice assistants. You may use Google Assistant, Siri, Apple HomeKit, or Alexa to manage the heating with your voice.

Wired/wireless thermostats

Boiler thermostats are available in both wired and wireless variants. A wired thermostat is typically less expensive. But, installing one usually necessitates hiring an expert to link the thermostat to the boiler.

A wireless smart thermostat is more costly than a wired thermostat, but it is considerably easier to install and control. The thermostat's control system is battery-powered. It interacts with a receiver connected to the boiler through radio waves. Since there is no cord between both the room thermostat and the boiler, installation is simplified. All you have to do is put the receiver in the boiler and mount the wireless room thermostat on the walls in the desired location. If you wish to install your receiver on a boiler that already has a wired thermostat, it's even easier. All you have to do is swap out the thermostat with a preferred receiver.

Add-on – Wireless Temperature Sensor

Add a Wireless Temperature Sensor to measure the temperature more accurately and to control several radiators in a room with one device.

Learn more

What is the additional benefit of a tado° boiler thermostat?

For those who want more influence over their heating, the tado° smart thermostat is one of the numerous alternatives. In a nutshell, it connects to an app and allows you to control the temperature in your house remotely. In addition, you can set heating schedules, and monitor your energy consumption. 

tado° provides effective climate control. It assists you in conserving energy and maximizing your comfort. And, it is compatible with a wide range of brands and is simple to set up. Moreover, it adjusts to your preferences and the environment in which you live. Also, tado° is compatible with the majority of smart home systems and can be operated via voice commands. For additional features, you can consider tado˚ auto assist.

How To Check If a Boiler Thermostat Is Working?

It might be a frustrating experience to discover if there’s anything wrong with your boiler thermostat. The thought of being without hot water for days and days, and having to spend a considerable amount on replacing it, is tiresome.

However, not all boiler problems are severe, and the most frequent concerns can be fixed quickly and cheaply. The most serious of them is a broken boiler thermostat.

When you turn on an old-fashioned immersion heater, the thermostat is also in charge of controlling the temperature in the tank.

There are several indicators that your thermostat is malfunctioning. The most evident is when you switch on or increase your central heating, and nothing occurs. Sometimes, you suddenly only have cold water coming out of both taps. It causes people to get concerned that their boiler has failed, although it may simply be a thermostat problem.

Alternatively, you may discover that your water is unexpectedly hot to touch. Perhaps, your central heating is set too high, and you cannot bring it down. Although this is just as inconvenient as a loss of heat, you may be certain that your boiler is still working.

Shut off the system and set the temperature on your controllers to zero. Carry this out for other room thermostats if you have them, to ensure that it's most probably a boiler thermostat issue. Turn it back on, but don't turn on the hot water until you've checked the central heating.

Check to see whether your boiler ignites by increasing the temperature on the boiler thermostat. If that doesn't, then there is one more option you can rule out before contacting an engineer. Replace the batteries in your remote thermostat device if you're using one; low power may be blocking the signal from reaching the boiler.

Does the boiler fire up when you turn your central heating again on? Wait for 15 minutes before checking if your traditional radiators are heating up to the temperature you set the thermostat. If you put it to 20°C, but your radiators are still merely lukewarm, your next step should be bleeding radiators. It will remove air before seeking expert assistance.

If your central heating is working as it should, turn it off and test your hot water. Switching the system back on and opening the hot tap is all that is required with a combi boiler.

Changing a thermostat is one of the more basic boiler repair procedures. However, it is not recommended to have expert knowledge of electronics.

How To Replace a Boiler Thermostat with tado°?

Replace a boiler thermostat with a tado° Wired Smart Thermostat:

If you wish to replace a boiler thermostat with a tado° Wired Smart Thermostat, here are the steps you can follow:

Step 1: Start the online installation assistant.

With the tado° app, scan the QR code on your Wired Smart Thermostat. Perform the installation instructions in the tado° app, which will walk you through the procedure step by step.

Step 2: Fill in the information about your heating system.

Mention your current heating system. It will aid the online installation assistant in determining if tado° is compatible with your heating system. Thus, it can generate customized instructions.

Step 3: Follow the instructions step by step.

Turn off the electricity to the heating system at the fuse box. This is critical to guarantee a secure installation.

Step 4: Remove your old room thermostat.

Remove your old room thermostat by following the installation instructions.

Step 5: Put the Smart Thermostat in Place

To learn how to connect and mount the Smart Thermostat, follow the customized online instructions. After you've completed the installation, now turn on your heating system.

Please keep in mind that these procedures are intended to give an idea of what an installation requires. Follow the installation instructions in the tado° app to successfully install and set your tado° devices.

Replace a boiler thermostat with a tado° Wireless Smart Thermostat:

If you wish to replace a boiler thermostat with a tado° Wireless Smart Thermostat, here are the steps you can follow:

For Steps 1 to 3, follow the procedure as given for replacing the boiler thermostat with a tado° Wired Smart Thermostat.

Step 4: Open your boiler or remove the existing controller.

Based on your heating system, follow the clear instructions in the tado° app. You will have to either remove your old controller or gain access to your boiler wire to install tado°.

Step 5: Install the Starter Kit - Wireless Smart Thermostat

For installing the Starter Kit - Wireless Smart Thermostat, follow the customized online steps. After you've completed the installation, you may turn on your heating system.

Starter Kit - Smart Radiator Thermostat V3+

Make your radiators smart. Save energy and maximise comfort. Available with vertical or horizontal mounting.

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How To Connect a Wireless Thermostat To the Boiler?

Connecting your thermostat to your boiler is a simple operation. 

To make a smart (wireless) thermostat operate, you have to install several components. Your old thermostat will get replaced, and you may need to attach a receiver box to your boiler. A hub connected to your home network may also be required to offer internet connectivity.

You must connect your new wireless thermostat to your boiler once installed so that the two devices can communicate. Depending on the thermostat manufacturer, this technique will be different.

A smart thermostat will need a power supply (battery or wired) and a receiver box, if one is needed, to connect to your boiler. To operate the system, use the screen and keys on the thermostat. 

When both devices are turned on, they may automatically connect in some circumstances. However, in some situations, you may need to press and hold numerous buttons simultaneously before releasing them.

For more information, consult the installation instructions provided by the manufacturer.

How To Connect tado° To Your Boiler?

To function with your boiler, you may install the tado° boiler wireless thermostat. You can use your phone to manage your heating from anywhere using a thermostat and an extension box.

The extension box must be paired with tado° servers and also your heating system during installation. This is accomplished through the Bridge. The Bridge is linked to a router through an ethernet connection. It helps to interact wirelessly with the wireless boiler thermostat and the provided extension box. 

To connect your system, pair the Bridge with the extension box. To do so, press the Bridge's 'Pair' button. Then push and keep the extension box's pairing key until the LED light starts flashing.

Following the directions on the tado° website is the best method to configure your machine. You'll have successfully linked your thermostat to the system after this is completed.

Using the smart thermostat/digital thermostat remotely should be positioned in a convenient area. It should best depict your home's temperature. Place it away from radiators and bright sunshine, both of which might cause the room temperature to be incorrect. It's best not to put it in your bedroom, which should be two or three degrees colder than the rest of your house. A smart mart thermostat is a recognized point of reference. 

So, your radiator should not have a thermostatic radiator valve attached. Thus, the hallway is typically the best position for your thermostat. In your home, this region maintains the most consistent temperature.

What Should Be The Temperature On A Boiler Thermostat?

In general, radiators should be set to 75°C (no higher than 80°C), and hot water should be set to 60°C (no higher than 65°C).

You risk acquiring Legionnaires' disease if you adjust your hot water below 60°C.

Bacteria can thrive if the water in your cylinder isn't hot enough, putting your health in danger. 60°C is too hot for harmful germs but not too hot for you.

The temperature of your tap/shower water must always be lower than that of your radiators.

Meanwhile, the recommended setting for your thermostatic radiator valves is number 3 and the room thermostat is about 18-20°C.


If you'd like to regulate your heating system even when you're not at home, a smart (wireless) thermostat might be helpful. This type of technology allows you to operate your boiler from anywhere using a smart device like a smartphone or tablet. tado° helps you intelligently heat and cool your room temperature. So, when you want to save more energy and money, choose tado°.