Siemens 331-2974 Pneumatic Damper Actuator, No.4, 2-3/8″ Stroke, Hesitation, Side Mount

Siemens 331-2974, Damper Actuator, Pneumatic, Number 4, 2-3/8″ Stroke, Unit Ventilator Hesitation Model.

This 331 Number 4 Pneumatic Damper Actuator has a 2 3/8″ stroke for unit ventilators and is a rugged, metal-fabricated device that provides gradual or positive actuation of HVAC and fire/smoke dampers. This hesitation model actuator has a nominal spring range of 2 to 3 and 8 to 13 psi, is fixed bracket mounted and provides minimum ventilation without separate damper/actuator. This actuator has an air connection of 1/8″ NPT female with a dual barb elbow fitting for 1/4″ OD tubing.