Honeywell MS4120F1006 Actuator

The Honeywell MS4120F1006 is a high-torque, Fast Acting Two Position Actuator designed for reliable fire and smoke damper control in commercial HVAC systems. Operating on 120Vac, this spring-return motor delivers 175 lb-in torque to ensure positive closure during power loss or emergency signals. It utilizes an SPST control signal and features a self-centering clamping adapter that streamlines installation on 3/8" to 1.06" round or 3/8" to 11/16" square damper shafts. With a 15-second nominal driving time and a matching 15-second spring return, it meets rigorous safety requirements for fast-acting applications. The NEMA 2 rated housing and manual operation crank provide durability and field flexibility, while the -40 to 130 degree ambient temperature range ensures performance in demanding mechanical rooms. This unit is electronically identical to the MS4120F1006/U model, making it a direct drop-in replacement for standard Honeywell Fire and Smoke Actuator retrofits.

Key Benefits for Contractors

• High Torque Output: Provides 175 lb-in of force, capable of driving large dampers or multi-section assemblies without stalling.
• Rapid Response: 15-second drive and spring return speeds ensure compliance with critical fire safety ventilation sequences.
• Universal Compatibility: The self-centering shaft adapter reduces the need for additional mounting hardware on various shaft geometries.
• Robust Environmental Rating: Designed to operate in 5-95% RH non-condensing environments, maintaining integrity in high-humidity zones.
• Simplified Wiring: 120V line voltage operation with SPST control simplifies integration into existing building automation and fire alarm circuits.

Common Questions

What is the difference between the MS4120F1006 and the MS4120F1006/U?
There is no functional or technical difference between these two part numbers; the "/U" suffix simply denotes a trade-packaged version, and they are completely interchangeable.

Which damper shaft sizes are compatible with this actuator?
The unit accommodates round shafts from 3/8" to 1.06" and square shafts from 3/8" to 11/16" using the integrated self-centering clamping mechanism.

Can this actuator be manually positioned during a power outage or installation?
Yes, the MS4120F1006 includes a manual operation crank that allows technicians to lock the damper in position for testing or commissioning when power is unavailable.

Disclaimer: While we strive for 100% accuracy, product data and specifications are subject to change. Please contact our team to confirm compatibility or technical details before purchasing.