Additional specifications and description
Shut-off dampers are also known as gastight dampers, as their name suggests, their purpose is to block off ducts while being as airtight and reliable as possible. They can be found in larger HVAC systems, as it is sometimes required to shut off or balance airflow rates in the high-pressure ductwork.
Aerotechnik shut-off dampers are easy to operate thanks to a convenient handle with a self-locking mechanism, meaning their adjustment does not require any tools. As they are press-fit and do not require the use of insulating tape, the shut-off dampers are very aesthetically pleasing, making them suitable for use in visible duct runs. The shut-off dampers can be operated in temperature ranges between -15 °C to +100 °C and allow an inflow velocity of up to 10m/s.
The dampers can remain airtight in pressures of up to 1000 Pa in the direction of the airflow, according to EN 1751 Class 4 (certified by German Technical Inspection Authority - TÜV) for diameters from 80 mm to 400 mm and up to 10 m/s air velocity.
Shut-off dampers play an important part in maintaining the airflow inside the ventilation system, as depending on the situation air in the system either has to be trapped inside or let out. The purpose of shut-off dampers is to block off airflow in a duct run, which makes them useful both during the normal operation of the system and during emergencies. Under normal circumstances, they help control the amount of air being pumped in a duct run, and in an emergency, they can block off dangerous gasses or smoke from a fire. Please note that, unlike fire-resistant dampers, standard ventilation shut-off dampers cannot withstand flames or heat from fire.
Shut-off dampers can also help reduce heat losses in the HVAC system as they are exceptional at trapping heat inside duct runs. They allow for better heat retention, which means less energy wasted.
Although not their primary purpose, shut-off valves can also prevent foreign objects from entering the system.
Construction and installation:
The body of the damper is constructed out of laser welded galvanised steel (using the Sendzimir process). The precise manufacturing method ensures that there is no protruding fold at the seam and that the inner surface is as smooth as possible. This helps maintain good airflow and prevents dust and dirt build-up. The oval-shaped metal blade of the damper does not impede airflow or induce excess noise/pressure loss, and it remains airtight under up to 1000 Pa of pressure. The male-male ends of the ventilation piece are equipped with EPDM rubber gaskets, making installation or disassembly very easy - just insert the spigots into the duct. The damper does not require additional sealant during installation, even if the duct is slightly canted or poorly trimmed. The EPDM rubber seals offer an airtightness class D according to EN 12237, and the material is also resistant to mildly aggressive vapours and chemical products.
Aerotechnik shut-off dampers are suitable for installation in horizontal and vertical duct runs. They don’t require any maintenance after installation.
Please note that according to EN 12097, the duct system and the shut-off damper must be accessible for operation and maintenance. The final airtightness of your ventilation system depends on several factors, for example, the installation method.