Siemens Building Technology 256-02011 1/2" FXUM Normally Closed Hydronic Control Valve 4Cv 2-Way

The Siemens Building Technology 256-02011 is a 2-way, normally closed (NC) hydronic control valve designed for terminal unit HVAC applications such as fan coil units, unit ventilators, and other hydronic heating and cooling systems. With a 1/2-inch female × union male (FXUM) end connection, this valve integrates easily into standard hydronic piping without the need for additional union fittings.

Key Features:

• Valve Body Size: 1/2 inch (DN15)
• End Connection: Female × Union Male (FXUM) for simplified installation and serviceability
• Action: Normally Closed (NC) — valve closes when actuator is de-energized for fail-safe operation
• Flow Coefficient (Cv): 4.0 — suitable for low-to-medium flow hydronic terminal units
• Close-Off Pressure Rating: 10/15 PSI, compatible with typical building hydronic system pressures
• Actuator Mount: Designed for use with a 2-inch (Siemens standard) actuator interface
• Compatible with Siemens SQS and SKD/SKB series actuators (sold separately)
• Suitable for chilled water, hot water, and condenser water applications

The union male end connection makes this valve particularly serviceable — the actuator and valve body can be removed from the piping without disturbing the union connections, reducing maintenance downtime. As a Siemens Building Technology product, it is built to meet the quality and longevity demands of commercial building automation and HVAC controls systems.