An important part of designing an air curtain system correctly is the situation of the building. Two different installation variations are used depending on whether there is excess pressure or low pressure in the building: installation with the air roll rotating inwards (IDW) or outwards (ADW).
Various device options within these two types of installation make it possible to achieve the optimal effect for the building conditions concerned.
Air roll rotating inwards.
Air is drawn in from the direction of the building and discharged above the door. This creates an air roll whose direction of rotation is directed into the room. This IDW method for installing an air curtain system is in principle the most favourable method in terms of energy. The preferred application area: to equalise pressure or where there is excess pressure. For small and medium-sized buildings where no employees are permanently stationed in the door area.
Air roll rotating outwards
Air is drawn in above the door and the discharge nozzle is in the building. This creates an air roll whose direction of rotation is directed outside, counteracting the cold air flowing into the building. This achieves a marked increase in the screening performance. There is less air movement in the entrance area. As a result of the lower temperatures in the air intake area, the heat output is greater than with the IDW air roll rotating inward type of installation. A frost protection thermostat should be fitted with the ADW installation. The preferred application area: where there is low pressure.