3 Way, Brass, T-Port, FNPT, Ball Valve, Direct Mount

Reliable Flow Control – Weil-McLain 640-000-088 3-Way Zone Valve for Hydronic Systems

The Weil-McLain 640-000-088 3-Way Zone Valve is purpose-built to manage water flow in hydronic heating systems with efficiency and precision. Designed for use in loop control and diverting applications, this valve enables controlled distribution of heated water to different zones—maximizing system performance while supporting consistent indoor comfort.

This component is engineered to integrate seamlessly with Weil-McLain boilers and other standard hydronic setups. Its brass body and dependable actuator provide long service life in residential and light commercial heating systems.

Application Advantages

• 3-Way Configuration – Allows for precise diverting or mixing, depending on system design needs.
• Thermal Motor Actuation – Ensures smooth operation with minimal noise and long-lasting reliability.
• Threaded Connections – Standard NPT ends simplify installation and system integration.
• Field Serviceable Design – Motor and valve components can be replaced independently when needed.

Key Specifications

• Manufacturer Part Number: 640-000-088
• Valve Type: 3-Way Zone Valve
• Material: Brass Valve Body
• Connection Size: 1" NPT
• Control: 24V thermal actuator (motor only sold separately in some configurations)
• Applications: Hydronic zone control in closed-loop heating systems

Installation Guidance

While this valve features standard NPT ends for quick installation, proper system balancing and electrical connection to compatible 24V zone control wiring are essential. Contractors should confirm valve orientation and wiring against system design. Always test for full open/close travel during commissioning.

Designed for Contractors Who Expect More

The 640-000-088 offers the performance and durability heating professionals rely on. It’s ideal for use with Weil-McLain’s Ultra, CGa, or Evergreen boiler systems, but is equally effective in custom hydronic installations where zoned comfort control is required.

Professional Features Summary

• 3-Way Brass Valve Body – For diversion or mixing in closed-loop water systems
• Thermal Actuation – Quiet, dependable operation under 24V control
• Threaded Ends – Compatible with common hydronic fittings and tees
• Service-Friendly Design – Motor and valve can be accessed and replaced as needed

Trust Weil-McLain Performance

Built to meet the expectations of HVAC professionals, the Weil-McLain 3-Way Zone Valve offers efficient control, installation flexibility, and long-term dependability. Whether you're retrofitting an older system or building new, this component provides reliable flow control in demanding heating environments.