A heater is the best infrared heating device with a fuel burner on the market. Weltem or Airrex heaters are suitable for use in indoor as well as outdoor conditions without the need for a separate flue tube. In order to heat a 500 m2 room, the heaters consume only 2-3 litres of diesel or biodiesel fuel per day. Unlike traditional fan heaters, infrared heat spreads evenly in all directions and feels pleasant even when standing next to the heater. The heater has durable wheels which make it easy to move around.