• Energy saving
  • Hydronic heating
  • Radiators

A guide to low temperature radiators

Our common goal to meet climate ambitions is driving us to heat our buildings as efficiently as possible. Modern insulation standards are already a big step forward in this mission, but energy-efficient heating systems supported by low temperature radiators are a must if we want to meet our net zero target by 2050.
A guide to low temperature radiators

How do low temperature radiators work?

Whereas the water circulating inside a traditional radiator is about 70 to 80°C, for low temperature radiators this is somewhere between 30 and 50°C. So, both the supply temperature of the central heating water and the surface temperature of the radiator are much lower.

Additionally, the kind of heat emitted by a low temperature radiator also differs from a conventional radiator. Traditionally, a radiator will provide about 65% convection heat, meaning the air around the radiator heats up on its warm surface, rises above the radiator and gradually heats the air in the room. 35% is radiant heat that is felt more directly when the heat rays emitted by the radiator penetrate the room and hit the objects, people and surfaces that are present.

When the flow temperature of a radiator drops below 40 °C, the convective share of the heating is significantly reduced, as the temperature differences between the radiator and the warming air lead to lower buoyancy forces. Low temperature radiators such as the Ulow E2 use integrated fans to support the convective heat dissipation and increase the total heat output. The innovative E2 technology allows the controller to switch automatically between operation modes and activate the fans as needed.

The Ulow E2 is a great type of radiator to use with a low temperature heating system provided that power supply is available near the radiators. If this is not the case, you can also adjust the size of the radiators to increase the radiating surface, thereby enlarging the available surface for producing radiant heat, which is effective even at very low temperatures.

What are the requirements for installing low temperature radiators?

Before you install low temperature radiators, it’s vital that the building’s insulation meets modern standards. Low temperature heating will only be worthwhile if the insulation can help to keep the temperature at the set level. Otherwise, it will be nearly impossible to ensure optimal thermal comfort.

Moreover, low temperature radiators need to be combined with a suitable heating system such as a heat pump, condensing gas boiler or low temperature boiler for maximum efficiency. The good news is that there is often financial support available for the installation of such heating systems in the form of government grants or subsidies.

Advantages of low temperature radiators

1. Low temperature radiators are very energy-efficient.

Since the flow temperature of the water drops significantly, low temperature radiators need about 30% less energy to heat a room than traditional radiators. This means that they are a very sustainable heating solution on the one hand, and very cost-effective on the other hand. That’s a win for the environment and for our wallet.

2. Low temperature radiators ensure an even heat distribution.

Traditional radiators tend to be less responsive to temperature changes than low temperature radiators. So instead of possible cold spots and drafts, the room is heated up quicker and the heat is spread more evenly throughout the space.

3. Low temperature radiators create a healthier indoor climate.

Low temperature radiators with large heating surfaces produce less powerful air flows, which reduces the amount of suspended dust particles in the air and creates a healthier indoor air quality. On top of that, the lower surface temperature of the radiators reduces the risk of scorch marks that can otherwise cause irritation to the airways.

Downsides of low temperature radiators

1. Low temperature radiators are only compatible with certain heating systems.

As mentioned above, you need a heat pump, condensing gas boiler or low temperature boiler if you want to maximise the efficiency of low temperature radiators. This can potentially be a stumbling block if you’re not looking to update the entire heating system.

2. Low temperature radiators need a large heating surface.

To ensure optimal thermal comfort, low temperature radiators are larger than conventional radiators. This can make them harder to fit into an interior design. Luckily, innovative product design and technology allows us to provide a fitting answer with low temperature radiators such as the Ulow E2.