Does the heat also spread in large rooms?

Yes, it does. Infrared heat spreads through very long distances. It does not need a fan for that – infrared heat heats materials, such as walls, floors and items in the room.

Why is infrared heat more efficient than a ventilator?

Infrared radiation heats materials.  Fan heaters heat the air. For example, if you open a window, all the heated air goes out and is replaced by cold air. The materials heated by infrared radiation save the heat and continue to heat the room even after the room has been ventilated. Fan heaters have to start all over again, thus consuming more energy. This is why our heaters are considered an extremely efficient and economic heating source for temporary facilities.

How is it possible that the burned diesel fuel does not leave behind any odour?

If the fuel has been almost completely burned, it does not leave behind any odour or dangerous residue. Carbon monoxide is formed as a result of incomplete burning. After more than 20 years of product development, Weltem and Airrex have polished the working process to perfection.

Why is there some kind of smell when the machine starts or finishes working?

When the heater starts/finishes working, a small amount of the smell of fuel may be released from the exhaust tube, because the burner cannot completely burn the fuel at the start or end of the process. The odour is not hazardous and can be reduced by using biofuel.

How can I be sure that the heater does not emit toxic exhaust gases?

The exhaust gas emission of Airrex and Weltem heaters has been examined and measured at the energy-technology laboratory of Kymenlaakso University of Applied Sciences in Finland.

Why does my heater consume more fuel than indicated by the manufacturer?

Weltem WHO-095, WHO-135 and Airrex AH-300 consume 0.9-1.24 litres per hour in working mode. Fuel consumption depends on the desired temperature level, roof and wall insulation of the room, number of windows and doors and the frequency of their opening/closing, or whether any cold items have been brought to the room, etc. The heater consumes more fuel at the start of the working process, because the materials are still cold. Once they have become warm, fuel consumption drops significantly.

Can the heaters be started by using the cigarette lighter receptacle of a car?

Yes, they can. At least a 150W inverter is required. So you can also use the heater in trailers or caravans.

I have been using the heater for a few days now. There are water droplets on the windows. Does the heater really create so much humidity?

The infrared heater does not create enough humidity for it to condense on the surface of the window. If you are using the infrared heater for the first time and have previously been using fan heaters, come condensation may appear on the windows. This is due to the fact that infrared radiation starts to heat the materials in the room, all the while releasing the humidity stored in them, which may then become condensed on the windows. Once condensation has appeared, we recommend keeping the temperature of the heater at 20 °C so it will remove the excess humidity from the room.

What kind of preparations do I have to make in order to start using the new heater?

The infrared heater does not require any special preparation. Fill the tank with fuel, and it is recommended to first start it outdoors or in a well-ventilated room. A new heater may emit odours from production residue, such as the smell of the powder paint warming up, etc.