Siemens Building Technology 257-02045 Valve Assembly

The Siemens Building Technology 257-02045 is a professional-grade 2-port pneumatic control valve assembly designed for high-accuracy regulation of hot or chilled water in terminal units like convectors and fan coils. As part of the Powermite 599 MT Series, this 3/4" NPT x Union Male assembly features a normally open configuration and a forged brass body with durable brass trim. Engineered for a 6.3 Cv flow capacity, it utilizes a modified equal percentage flow characteristic to ensure linear heat output and stable room temperature control. The integrated pneumatic actuator operates within a standard 3-8 PSI spring range, providing reliable mechanical force for precise valve positioning. Its compact design allows for easy installation in tight mechanical spaces, while the ANSI Class 250 rating ensures robust performance in demanding HVACR environments. This assembly is built for medium temperature applications ranging from 35°F to 250°F, making it a versatile choice for contractors focused on long-term system efficiency and maintenance-free operation.

• Precise Flow Control: The 6.3 Cv rating and modified equal percentage characteristic prevent hunting and optimize heat transfer.
• Durable Construction: Forged brass body and internal brass trim resist erosion and scale buildup in industrial water loops.
• Simplified Installation: The 3/4 inch NPT x Union Male connection allows for fast piping alignment and easy actuator removal without tools.
• High Pressure Rating: Rated for ANSI Class 250 service, suitable for high-rise terminal unit applications.

• What is the default position of the valve upon loss of air pressure? This 2-way normally open assembly will fail to the open position if control air is lost, ensuring continuous flow for freeze protection.
• Can this assembly be used for steam applications? While primarily used for water, the Powermite 599 MT series is rated for medium temperature service up to 250°F; however, always verify specific steam pressure limits per Siemens technical instructions.
• Is the actuator field-replaceable? Yes, the pneumatic actuator is designed for direct-coupled installation, allowing for quick field service or replacement without disturbing the valve body piping.

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.