Mechanical Supplies

Motorized Volume Control Dampers

About

Volume control dampers fitted with two-position or modulating actuators, in low-leakage or standard construction, with 0-10 V, 4-20 mA or floating control and optional position feedback. Blade and jamb seals are specified where the closed leakage rate is part of the control strategy.

Application

Used as fresh air, return and mixing dampers on air handling units, as zone isolation dampers, and on car park and stairwell ventilation where fans serve more than one zone. In an economiser sequence the three dampers modulate together against the mixed air temperature, which is why leakage class matters: a fresh air damper that leaks 5% in a Gulf summer is a permanent load on the coil.

Standards & Reference 5 cited

AMCA 500-D
The laboratory method for testing dampers: air performance and, critically, leakage. Leakage class is what a smoke control or energy calculation depends on.
AMCA 511
The certified ratings programme for air control devices: dampers and louvres carrying a verified rather than a claimed rating.
UL 181
Factory-made air ducts and air connectors: the listing a flexible or fabricated duct carries.
ASHRAE 90.1
The energy standard for buildings: fan power limits and efficiency requirements that constrain equipment selection.