What is displacement ventilation?
Displacement ventilation is an effective ventilation principle that supplies air at floor level at a low velocity. The supply air spreads across the floor surface and is influenced by heat sources in the room, after which it rises towards the ceiling together with the warm air from these heat sources. The warm and contaminated air is then extracted at ceiling level, resulting in a comfortable indoor climate.
Displacement air diffusers are an excellent choice for rooms with:
- Large floor areas with medium to high ceiling heights (greater than 3 metres). Higher ceiling heights provide more space for contaminated air to be stored above the occupied zone. This makes displacement ventilation particularly suitable for larger spaces such as industrial facilities, retail environments, classrooms, and sports halls.
- Heat sources. The supply air rises when it comes into contact with heat sources such as machinery and people in the room, creating two zones: an upper zone with contaminated air and a lower zone with “clean” air.
- Limited cooling demand.
Displacement ventilation is often energy efficient, as only the occupied zone needs to be ventilated, in contrast to mixing ventilation where air is mixed throughout the full height of the room.
Swegon’s flexible distribution system VARIZON®
The placement of displacement diffusers is crucial, as they are usually installed in the occupancy zone. This can pose a challenge with regard to room layout, furnishing and other factors. It is particularly important not to place the air diffusers near seated people in order to avoid unpleasant draughts.
To accommodate the challenges related to the location of displacement diffusers, Swegon has developed a flexible distribution system called VARIZON®. VARIZON® consists of rotatable air deflectors integrated into our traditional displacement diffusers to enable an adjustable distribution pattern. By changing the distribution pattern, it can easily be adapted to the occupied zone’s intended use, while also future-proofing for upcoming changes in the room’s layout or use. VARIZON® helps increase comfort and maximises flexibility.
Unique combination that alternates between heating and cooling
Swegon’s BOC displacement air diffuser, known as a Booster diffuser, is a unique displacement diffuser that can switch between mixing and displacement ventilation. The upper section of the air diffuser consists of nozzles that direct the air down into the room when heating is required (Booster function). The lower perforated section of the air diffuser functions as a displacement diffuser which supplies cool air slowly to the room when cooling is required. The VARIZON® distribution system allows the distribution pattern to be adjusted to prevent draught.
Unlike traditional displacement diffusers, BOC takes up no floor space as the product is installed suspended from the ceiling or against the wall.
Explore Swegon’s range of displacement air diffusers
Swegon offers a wide range of displacement diffusers in different variants, customised to suit the function, geometry and design of the room and the type of building system and HVAC solution selected for the building. Swegon’s range of displacement air diffusers is presented below.
Showing 10 of 10 products
References
Find out more about displacement ventilation
Gain in-depth expertise about the principle behind displacement ventilation, its benefits and the environments it is best suited for.
Frequently asked questions about displacement air diffusers
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