Barber Colman MK-3121 Actuator

The Barber Colman MK-3121 is a pneumatic damper actuator designed for precise proportional control in HVAC systems. Featuring an adjustable stroke length and operating within an 8 to 13 psig spring range, it is suitable for applications requiring accurate modulation of dampers.

Technical Specifications

  • Model: MK-3121

  • Type: Pneumatic damper actuator

  • Effective Diaphragm Area: 8 in² (52 cm²)

  • Spring Range: 8 to 13 psig

  • Stroke Length: Adjustable from 2″ to 4″ (51 to 102 mm)

  • Maximum Air Pressure: 30 psig (207 kPa)

  • Air Connections: 1/8″ FNPT

  • Mounting: Universal mounting options

  • Construction: Die-cast aluminum housing with beaded molded neoprene diaphragm

  • Operating Temperature Range: -20°F to 160°F (-29°C to 71°C)

  • Condition: New

Key Features

  • Provides precise proportional control for HVAC dampers

  • Adjustable stroke length allows for flexibility in application

  • Spring return mechanism ensures safety during air pressure loss

  • Compact design suitable for various installations

Compatible Applications

  • HVAC systems requiring modulating damper control

  • Ventilation and exhaust systems

  • Industrial process control requiring pneumatic actuation

Installation & Maintenance Notes

  • Ensure proper alignment during installation to prevent binding

  • Verify pneumatic connections are secure and leak-free

  • Regularly inspect actuator for signs of wear or damage

  • Follow manufacturer guidelines for maintenance procedures


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