Thermostatic actuator DANFOSS 088H3216 normally closed 24 V for valve control

DANFOSS thermostatic actuator 088H3216 is a normally closed (NC) electric actuator designed for 24 V control of heating and cooling valves. It provides reliable on/off operation for radiator and zone valves in HVAC systems, enabling automated temperature regulation and integration with room thermostats or building management systems. The compact design and standard mounting allow use in retrofit projects as well as new installations where a 24 V actuator is required.

Advantages

The actuator offers dependable NC operation with consistent stroke control, ensuring valves remain closed when power is removed and open when energized. Its 24 V drive is compatible with common low-voltage control circuits, and the robust mechanical construction supports long-term use in residential and light-commercial heating or cooling installations. The unit's straightforward electrical connection and mounting reduce installation time and simplify maintenance.

Suitable for

• Control of radiator valves in central heating systems
• Zone valve actuation in multi-zone HVAC installations
• Replacement of mechanical or incompatible actuators during retrofits
• Integration with 24 V thermostats and controllers

Key specifications

• Operating mode: normally closed (NC)
• Supply voltage: 24 V (AC/DC as specified by system requirements)
• Control type: on/off (binary) valve actuation
• Typical application: radiator and zone valves for heating and cooling
• Mounting: direct valve mounting compatible with standard valve interfaces
• Operating environment: indoor HVAC applications

How to use

Mount the actuator on the compatible valve body following the valve manufacturer's mounting instructions and ensure proper mechanical coupling. Connect the 24 V control wires to the supply and control terminals according to the system wiring diagram, observing polarity and local electrical codes. Commission the actuator by energizing the supply and verifying that the valve opens when 24 V is applied and returns to the closed position when power is removed. Verify stroke and seating to ensure leak-free valve closure.

Usage recommendations

For reliable operation, use the actuator within specified voltage and ambient conditions, avoid exposure to direct weather or excessive moisture, and perform periodic inspections of electrical connections and mechanical mounting. When replacing an existing actuator, confirm compatibility with the valve spindle dimensions and torque requirements. If used in control systems, ensure appropriate protection and switching elements are in place for the 24 V supply.