Siemens Building Technology 257-02046 Valve Assembly

For high-demand terminal unit control, the Siemens Building Technology 257-02046 serves as a reliable 2-way normally open valve assembly designed for precision in HVAC systems. Built with a 1-inch NPT female-to-female connection, this forged brass body valve features a durable brass trim and maintains a 10 Cv equal percentage flow characteristic, ensuring stable control of hot or chilled water in convectors and heat exchangers. The integrated 2-inch pneumatic actuator operates within a 3-8 PSI spring range, allowing the valve to return to its default open position during signal loss—a critical fail-safe for preventing frozen coils in cold climates. Designed to handle medium temperatures from 35°F to 250°F and rated for ANSI Class 250 pressure environments, this Siemens Powermite MT Series assembly is a staple for contractors prioritizing long-term performance and high close-off reliability in standard building management applications.

• Fail-Safe Operation: The normally open configuration ensures constant flow during pneumatic signal loss, protecting systems from freezing.
• Precise Modulation: Features an equal percentage flow characteristic for linear heat output and superior temperature stability.
• Rugged Construction: The forged brass body and brass trim offer excellent corrosion resistance and mechanical strength in 125 PSI WOG applications.
• Contractor Friendly: Standard 1-inch NPT threads and a compact footprint simplify installation in tight mechanical headers or plenum spaces.

What is the maximum fluid temperature for this assembly?
The valve is rated for media temperatures ranging from 35°F to 250°F, making it suitable for both chilled water and low-pressure steam applications.

Can I install this valve in any orientation?
For optimal performance and to reduce internal wear, it is recommended to install the valve vertically with the pneumatic actuator pointing upwards.

What size air line connection is required?
The 2-inch pneumatic actuator typically utilizes a 1/8-inch NPT air connection for the 3-8 PSI control signal.

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.