Siemens 331-2904 Pneumatic Actuator with pivot mounting bracket,
Designed with a 4-inch (102 mm) stroke, the No. 4
Pneumatic Actuator is a rugged, metal-fabricated device
that provides gradual or positive actuation of HVAC and
fire/smoke dampers.
Applications
Recommended for control of outdoor, return air, exhaust,
face and bypass, fan discharge, and static pressure
control dampers, the No. 4 Pneumatic Actuator also is
excellent for controlling specialized dampers and air
valves in terminal units, such as unit ventilators and
mixing boxes.
The No. 4 actuator hesitation model is frequently used
to operate the outdoor air damper on unit ventilators and
mixing boxes.
An actuator marked with an asterisk (*) is a component
recognized under UL’s Damper Actuator category
(EMKU2) for use on fire dampers and leakage-related
dampers.
