We have listed some frequently asked questions about our products with answers. A great deal of information about the products can be found in our manuals; you can also take a look there for installation questions. If you cannot find the answer to your question, you are warmly welcome to contact us.

About underfloor heating

How far does the filler go?

A good rule of thumb is 1.7 kg per m² and mm of filler thickness. For a Cable Kit for example, you should reckon on filler thickness of 5 mm. That means you will use about 8.5 kg/m².

Do I need to use special filler or fix to install underfloor heating?

No, there is no need to use a special filler. But we do recommend using a fibre-reinforced filler for stability.


Cable Kit can be laid in open wooden joisting. To calculate how much cable is needed: (Room area/0.6) x number of lengths per section. Then choose the nearest shorter cable length. In most cases each section is 60 cm. With 4 lengths/60 cm section, the output will be about 75W/m². With 3 lengths/60 cm section, the output will be about 55W/m². Maximum permitted output is 80W/m².Read more about installation in Cable Kit installation instructions.


The cable should always be on top of any mesh.

How far from the wall can I lay the cable (Cable Kit)?

The gap from wall to cable should be at least 3 cm.

Is there a risk of moisture rising with underfloor heating?

There is a risk of moisture rising if the concrete slab is poorly insulated. Laying underfloor heating directly onto the concrete floor in an uninsulated cellar is not a good idea, not even if the concrete slab is thick. Old slabs have often been poured onto an uneven surface and can be very thin in places. The heat disappears down into the concrete and your energy consumption increases. When you heat the concrete slab instead of the room, a heat cushion occurs in the ground below the concrete. If the underfloor heating is later turned off, the concrete slab cools faster than the ground. Moisture from the ground can then be transported upwards. This is called reversed moisture flow. You can easily avoid the problem by laying insulation on the existing floor before laying the underfloor heating. A particularly good choice for cellars: Cable Board together with Cable Kit 300.

How much EBECO FOIL can be installed on one thermostat?

An EB-Therm thermostat (regardless of model) can handle 30-35 m² of foil. With larger areas, you should connect the thermostat via a contactor.

Can I have underfloor heating under wall to wall carpet?

Yes, you can lay wall to wall carpet on the floor even if you have installed underfloor heating. There is no risk of overheating, because the floor sensor ensures that the temperature does not get too high. On the other hand, it is not particularly energy smart. The carpet stops the heat from rising and there can be a big heat loss down into the ground.


For floors in wet rooms, a sealing layer is required. The same is true if you do not install underfloor heating. For more information about floor construction and sealing layers under tiles and natural stone floors – see PER's industry rules issued by the building tile council. There are also advice and recommendations for floor construction and sealing layers at AB Svensk Våtrums-kontroll. This says among other things that the sealing layer must always be above the underfloor heating system.

Why is it not warm in my bathroom in the cellar, even though I have underfloor heating and a well-insulated floor?

This is probably due to poorly insulated walls and cold surroundings. This is especially true if you have laid a heated floor in a bathroom or other small room and left the rest of the cellar cold. If walls are poorly insulated, there is a risk that the heat will leak out into the rest of the cellar. This means that it can be hard to raise the temperature inside the small room. This is true for all kinds of heating in cellars, not just underfloor heating. It is quite simply the physical law of temperature distribution that causes heat to move towards cold. This can be avoided by insulating the walls or also heating the rest of the cellar.

Can Adesilex be put onto chipboard?

Mapei's data sheet for Adesilex P4 says "Never use Adesilex P4 on wood or wood composites." Cable Board functions as a motion absorbing layer however. If clinker in P4 is put directly onto chipboard, P4 is not sufficiently elastic to take up the movement in the chipboard and the joints will probably crack. If Cable Board has been laid on the other hand, movement will be absorbed by the insulation board and nothing will happen to the floor.

About thermostats

Why is the LED on the thermostat flashing (green or red)?

For EB-Therm 350/355 the following applies: When a fault occurs, EB-Therm turns the heating off. The LED flashes red and green alternately. The LCD display shows a flashing error code as follows:
Error 1: Short circuit room sensor.
Error 2: Interruption room sensor.
Error 3: Short circuit floor sensor.
Error 4: Interruption floor sensor.

Where should the sensor cable be placed?

The sensor cable should be in the floor below the thermostat. It should be exactly between two lengths of heating cable.

The hole in the wall for the thermostat is too big. What should I do?

If the existing frame for the thermostat does not cover the hole, you can fit a Backplate, item number E 85 816 97. This matches the Eljo Trend frame system.

Why aren't the buttons on the thermostat working?

The pad may be locked. If it is, a small key is shown on the display. To unlock it. EB-Therm 350/355/205: hold both arrows pressed in until the key symbol disappears. EB-Therm 300: hold any button in for four seconds. To lock it. Press the central button and scroll to LOCK. Confirm with the centre button to lock.

About snow melting on roofs

How can I avoid snow and ice problems around roof windows?

Roof windows are often covered by snow in the winter. When the temperature rises, the snow starts to melt because of heat leakage through the window. The melted snow runs off the window to the colder roof surface further down. The melt water freezes into ice, because the snow below the window prevents further run off. A pool of dammed-up water collects under the ice. This can cause water to begin to get into the house.

Make sure that the melt water always has a free run-off path from the window by removing snow and ice from around the window. The easiest way to do this is by installing heating cable around the lower edge of the window.

Takfönster utan snö och istakfönster med värmekablar

Special solutions

How can freezing of ground be prevented under freezer rooms and ice rinks, i.e. under floors and surfaces that are continuously chilled to minus temperatures??

You install Ebeco heating cable in the ground beneath the floor. With an insulation thickness of 20 cm and a temperature of - 30°C, the theoretical output requirement is about 7 W/m². However for practical reasons we recommend 15-30 W/m² with a cable that has 10 W/m. An extra heating cable is often installed as a spare.