Honeywell MP918A1057 Pneumatic Damper Actuator, Spring Return, 3-1/2″ Stroke

Description

Honeywell MP918A1057 Pneumatic Damper Actuator Overview

The Honeywell MP918A1057 is a high-force, spring-return pneumatic damper actuator engineered for reliable, precise damper positioning in commercial HVAC and building automation systems. With a generous 3-1/2″ stroke and a maximum operating pressure of 25 PSI, this actuator delivers the muscle needed to drive large or high-resistance dampers while maintaining accurate control throughout the full range of travel. The spring-return design ensures the damper fails to a safe, predetermined position in the event of air supply loss — a critical feature for life-safety and energy management applications.

Key Features

• High actuator force for demanding damper applications
• Spring-return action for fail-safe operation on air supply loss
• 3-1/2″ stroke for wide damper travel range
• 25 PSI maximum operating pressure
• 5–95% RH humidity operating range for broad environmental compatibility
• 5/32″ push-on barb fitting for pilot air connection
• 1/4″ push-on barb fitting for main air connection
• 10 PSI positive positioner span (5 PSI start) for accurate proportional control

Pneumatic Connections

The MP918A1057 features two distinct push-on barb connections for straightforward field installation. The 5/32″ barb serves the pilot signal port, while the larger 1/4″ barb handles the main air supply — eliminating the need for threaded fittings and simplifying tubing connections in tight mechanical spaces.

Positive Positioner

The integrated positive positioner with a 10 PSI span (beginning at 5 PSI) ensures the actuator accurately tracks the pneumatic control signal across the full stroke. This feature minimizes hysteresis and friction-induced positioning errors, making the MP918A1057 well-suited for VAV systems, economizer dampers, and mixed-air control applications where precise airflow management is essential.

Specifications

• SKU: MP918A1057
• Actuator Type: Pneumatic, Spring Return
• Actuator Force: High
• Stroke: 3-1/2″
• Maximum Operating Pressure: 25 PSI
• Humidity Range: 5–95% RH
• Pilot Air Connection: 5/32″ Push-on Barb
• Main Air Connection: 1/4″ Push-on Barb
• Positive Positioner Span: 10 PSI (starting at 5 PSI)
• Brand: Honeywell

Applications

• Commercial HVAC damper control
• Variable air volume (VAV) systems
• Economizer and mixed-air damper positioning
• Building automation and pneumatic control systems
• Outdoor air, return air, and exhaust air dampers