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Thermostatic Radiator Valves

Thermostatic radiator valves are devices fitted to radiators to adjust their temperature. Installed in each room, they help you maintain an ideal ambient temperature depending on the level of comfort you want in each area of your home. Whether they're traditional, electronic or smart, they're easy to use and allow you to save on your energy bill.

How thermostatic radiator valves work

A thermostatic radiator valve is installed on each radiator's hot water inflow pipe to adjust the flow of hot water. It's made up of several components: a valve or tap and a sensor.
  • The temperature sensor
The sensor on a thermostatic radiator valve measures the temperature of the room. The ambient temperature can vary depending on how the heating is set, as well as the time of day, the sun's rays shining through a window, the number of people in the room, the heat produced by devices being used, etc. Taking all these elements into account, a thermostatic radiator valve can more accurately adjust how the heating functions to maintain a consistent temperature in a room. This avoids heating a room unnecessarily or overheating it if the temperature is already sufficient.

The sensor can be incorporated into the valve or be separate to avoid giving an incorrect reading if the radiator is covered with a panel or is in an enclosed area.
  • The thermostatic valve
The valve is the control component strictly speaking. This is what regulates the flow of hot water according to the temperature read by the sensor. It usually has an adjustment knob that allows you to select the level of warmth in the room. This adjustment can be manual, in which case the valve has a graduated knob or lever with several positions corresponding to different degrees of heating. The adjustment can also be electronic or even remotely controlled if the product is smart.

Thermostatic radiator valves can be installed on all hot-water radiators, regardless of which type of boiler you have and the method of central heating (oil, wood, natural gas, etc.). They regulate the temperature in each room and can be used even if you already have a room thermostat in your home. This is perfect for fine-tuning your comfort based on the rooms in your home and your requirements.

Regulating the ambient temperature in each room

There's no need to maintain a uniform temperature throughout your home: it's better, both in terms of comfort and energy savings, to adjust the heating based on how each room is used.

The French environment and energy conservation agency (ADEME) also recommends a different temperature for each area of your home. In living areas such as the living room a temperature of 19°C is sufficient, or even less if you're not at home. In the bedrooms you don't need to heat to more than 16 or 17°C. The ambient temperature can even be less in corridors or unoccupied rooms (guest rooms, dressing room, etc.). Meanwhile, you need a high level of comfort in the bathroom for when you get out of the shower or bath: it's best to adjust the thermostatic radiator valve in this room to 20 or 21°C. Thermostatic radiator valves usually have a frost protection position to avoid heating when you're away for a longer period of time, without your home getting too cold.

Make energy savings with thermostatic radiator valves

Adjusting your heating therefore creates the right temperature according to each room and what you're doing. It's also an excellent way to make energy savings. According to the ADEME, fitting thermostatic radiator valves can help you save 3% to 5% on your energy bill, or even more if you get an electronic model with programming, if you use thermostatic radiator valves in addition to a room thermostat or if your lifestyle means you don't need an excessively soothing ambience in your home.

Aside from the energy savings made, this type of heating system is very environmentally friendly. Not only can you save on your natural gas or wood bill, you'll also cut your heating system's CO2 emissions. Discover all our products

Thermostatic radiator valves: low-cost installation

The other benefit of fitting thermostatic radiator valves is the low cost of the valves themselves. They're extremely affordable, and even sophisticated versions aren't overpriced. This allows you to quickly offset the price of the valves by saving on your energy bill.

It's also worth noting that if you include the cost of your thermostatic radiator valves in more extensive energy refurbishment alterations (insulation, installing double glazing, changing your heating system, etc.) you may also be entitled to various subsidies: the 30% energy transition tax credit ("CITE"), a means-tested subsidy from the French national housing improvement agency (ANAH) or even an interest-free eco-loan. Find out about the conditions for eligibility if you're having major renovations carried out in your home.

Why choose electronic thermostatic radiator valves?

As well as standard manually-adjusted products, electronic thermostatic valves are also available. These products allow you to adjust the temperature more accurately, usually to the nearest half-degree or even one tenth of a degree, and are easy to adjust thanks to a digital display.

The other benefit of an electronic thermostatic radiator valve is that you can program your heating based on your lifestyle: this allows you to set up programmes at different temperatures for when you'll be at home or out. There's no need to leave the bathroom radiator on full during the day or heat the living areas when you're not at home. These adjustments allow you to save even more energy and offset the cost of thermostatic radiator valves more quickly.

What are the benefits of smart thermostatic valves?

Thermostatic regulation products also include smart valves. Like other thermostatic radiator valves, these allow you to precisely control the warmth that each radiator produces based on the thermal environment and to set up different programmes based on how each area in your home is used. However, the benefits of smart valves don't stop there.

Each small valve can also be remotely controlled using a smartphone app, giving you control over your thermostatic valves wherever you are. You can even adjust the valves, and therefore the radiators, just by using your voice if they're compatible with the virtual assistants Google Home and Apple HomeKit.

What's more, if you feel that setting up heating programmes for during the day isn't enough, you can even create a detailed schedule that's adapted to your habits. Lastly, even if you have all this technology you can still manually adjust your smart valves by simply turning them, just like a standard thermostatic radiator valve.

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