Low temperature radiator: How to choose it

Low temperature radiators, also known as low consumption radiators or soft heat radiators, are a type of radiator that heats up to a maximum temperature of 50 degrees. At a time when many households are considering what central heating system is best, low temperature heating has the potential to appeal to many households. Unlike electric radiators, for example, this type of heating has a dual benefit: it’s economic and environmentally friendly. However, it is not always easy to choose the right low temperature heater because there are so many different models.

How does a low temperature radiator work?

What is the operating difference between a low temperature radiator and a high-temperature radiator?

The system for low and high temperature radiators is exactly the same: it is the water circulating inside the radiator that produces the heat. The main difference between the two types of radiators is the water temperature. Unlike traditional radiators, which have a temperature varying between 70 and 90 degrees, low temperature radiators have a temperature varying between 40 and 50 degrees maximum. It is important to note that in order to ensure optimal thermal comfort, low temperature radiators are larger than conventional radiators.

In addition, a low temperature radiator must be combined with one of the following heating systems:

  • A heat pump

  • A condensing boiler (using gas)

  • A low temperature boiler

  • A solar heating system

Depending on the country you live in there might be financial support for the installation of heating systems such as those. Indeed, for the installation of a heat pump, it is possible to benefit from a subsidy or a grant. It is also possible to benefit from the Domestic Renewable Heat Incentive (Domestic RHI), as the installation of a low-temperature radiator is part of a more ecological energy renovation approach.

It is important to know that for the installation of a low temperature radiator, it is necessary that your home has optimal insulation. Furthermore, it is not possible to use low temperature radiators with a high temperature boiler. Thus, it is not possible to partially replace your high temperature radiators with low temperature radiators. The installation of this type of heating system either requires a new home or a complete renovation of all the heating appliances in your home.

How do I look after my low temperature radiator?

You should bleed your radiator every year and remove sludge from it about every 5 years.

Netatmo Info

On most hot water radiators, you can easily install a Netatmo Smart Thermostat to program and control your heating remotely. Increase efficiency, save energy and enjoy lower heating bills!

What material with high thermal inertia should I choose for my low temperature radiator?

The term low temperature radiator is actually quite general. In fact, it can be made of various materials with high inertia. Because low-temperature water circulates through the pipes, it is important that the material used for this type of radiator allows for easy and rapid heat diffusion.

There are specific characteristics for each high thermal inertia material:

  • Cast iron: The inertia of cast iron is very high, which is a big advantage for low temperature radiators made of this material. It allows for optimal heating. One of the advantages of cast iron is that it is a robust material that ensures a long durability for the radiator. However, it is also the most expensive material to buy and the most massive and imposing, which can be disturbing when setting it up or for the aesthetics of your home. But also, cast iron has a very slow temperature rise, which is a big disadvantage.

  • Aluminium: Much more elegant than a cast iron radiator, the aluminium radiator will appeal more to households that value interior design. This material allows a wide range of designs and colours. Another advantage is that it generally has a very high thermal efficiency. Aluminium also ensures that your room heats up extremely quickly, as it contains less water than conventional radiators. This not only saves energy but also has a lower impact on the environment. Finally, aluminium is a light material, which means that no major work is required for its installation (especially for hanging it on the wall).

  • Steel: Steel radiators allow for a very fast temperature rise (much faster than cast iron for example). Among the steel radiators, you can find different models: horizontal radiator, tube radiator or panel radiator, etc.
    The low temperature system is not only for radiators but can also be applied to underfloor heating. In the case of underfloor heating, the water temperature is between 20 and 45 degrees.

What are the advantages and disadvantages of low temperature radiators?

The benefits

  • The heat generated by low temperature radiators is much softer than that of conventional radiators. The purchase of a low-temperature radiator therefore ensures a certain level of thermal comfort.

  • More economical heating: the longevity-price ratio for this type of heating is very high, which makes it a particularly economical heating medium compared to a conventional or electric radiator.

  • Healthier indoor air: the heat diffused by low-temperature radiators allows for thermal homogenisation inside homes, which reduces draughts and therefore dust particles suspension in your indoor air.


  • Size: soft heat radiators may not always be the most appropriate heating method due to their large size. Indeed, they are not always easy to install if you want to preserve the harmony of your interior. Nowadays, manufacturers are innovating in terms of design to reduce the size of this type of radiator.

  • The price: it is higher than other heating methods, but their longevity allows it to be cost efficient. The price of a low-temperature radiator varies globally between €100 for classic models and €2,500 for the most sophisticated models. It should also be noted that prices vary according to the materials used.

  • Compatibility: as mentioned at the beginning of this article, low temperature radiators can only be installed with some heating systems. This limits the possibilities of installation for some potential buyers.

Get the most out of your low temperature central heating

Connected thermostats allow you to create a heating schedule and to better manage your energy consumption.
According to the ADEME* (French Agency for Ecological Transition), the use of smart and/or connected thermostats would help to reduce the cost of heating bills for households.

According to the agency, these thermostats represent a "small but very profitable investment" as the savings in the first year are likely to cover their purchase price. The Intelligent Thermostat ON/OFF allows you to remotely program and control the room temperature of your home. It uses the thermal characteristics of your home to manage your wood stove or boiler with more finesse.

In conclusion, the purchase of a low temperature radiator can be expensive but in the long run, it is a choice that will allow you to make energy savings and therefore reduce your heating bills. Don’t forget that it is possible to benefit from subsidies or grants for energy renovation in your home depending on where you live. Although they are often bulkier than conventional radiators, recent models of low temperature radiators are increasingly adaptable to different interiors.