Fig. 14: Bend and spread the fixing tabs before
installation
Connecting the duct
Use screws to attach the damper to the ducting.
The damper casing has flange holes for duct con-
nection.
Seal the joint between the casing flange and the
duct in order to avoid pressure loss. Use sealing
tape, for example, and clamps or additional screws,
if necessary.
The movement of the damper blades must not be
obstructed by any attachment.
Commissioning and maintenance
Commissioning
Personnel:
HVAC technician
As part of commissioning, the non-return damper
must be tested for correct functioning.
NOTICE!
Start-up of fans with UL/KUL
Ensure a gradual start-up of fans to avoid a
sudden pressure increase.
NOTICE!
ARK-1 blade restrictors
Type ARK-1 non-return dampers have adjustable
blade restrictors, which can be adjusted as part
of commissioning.
Maintenance
Non-return dampers are maintenance-free with
regard to wear but must still be included in the reg-
ular cleaning of the ventilation system.
Commissioning and maintenance
Non-return dampers Types UL, KUL, WG-KUL, ARK, ARK-1
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