Schneider Electric (Barber Colman) AV-420 Linkage Kit

The Schneider Electric AV-420 Linkage Kit is a field-installable hardware set engineered for retrofitting and maintaining pneumatic control systems. Designed specifically to interface MK-4800 Series pneumatic actuators with VB-9XXX series valve bodies (1.5-inch to 2-inch), this Barber Colman AV-420 kit ensures precise mechanical alignment for mission-critical flow regulation. As a veteran technician, you know that maintainable air-handling stability depends on the 1-1/2" to 2" stroke calibration this pneumatic valve linkage provides. The rugged steel construction and die-cast mounting components are purpose-built to handle the 100-lb spring forces characteristic of the 11 sq. in. diaphragm actuators in the MK-48XX family. Utilizing the AV-420 actuator linkage during valve body replacements or actuator upgrades eliminates the guesswork in stem height adjustments for 2-way and 3-way mixing or diverting configurations. This HVAC control linkage is essential for ensuring your pneumatic systems close against flow accurately, maintaining the high-performance standards required in commercial building automation environments.

• Precision Compatibility: Seamlessly bridges MK-4801, MK-4811, and MK-4821 actuators to VB-9213, VB-9313, and other 1-1/2" to 2" valve bodies.
• Durable Construction: High-grade steel and aluminum components designed to withstand the vibration and thermal stresses of mechanical rooms.
• Standardized Installation: Simplifies field service by following standard F-23325 general instructions for consistent stem-to-piston connection.
• Flexible Mounting: Supports upright mounting above the valve centerline, with specific 45-degree positioning adjustments for steam applications.

Which actuators are compatible with the AV-420?
The AV-420 is designed exclusively for the Schneider Electric (formerly Barber Colman) MK-4800 series pneumatic actuators, typically used on larger globe valves.

Can I use this linkage on 1/2" to 1-1/4" valves?
No. For the smaller VB-7XXX or VB-9XXX valves (1/2" to 1-1/4"), you generally require the AV-400 or AV-401 series. The AV-420 is specifically dimensioned for the 1.5-inch and 2-inch valve bodies.

Does this kit include the replacement diaphragm?
This is a mechanical linkage kit containing the bracket and stem connection hardware. Actuator diaphragms (like the neoprene beaded type) must be ordered separately based on the actuator model.

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.