Thermostatic straight valve Comap R809, 1/2" connection, Kv 0.55, without preset

Thermostatic straight valve Comap R809 with 1/2" connection and Kv 0.55 is a compact control valve intended for hydronic heating systems. Supplied without preset, this valve is designed to regulate radiator or convector flow in response to a thermostatic head. Its straight-body design and standard 1/2" connection make it compatible with common residential and light commercial installations where space-efficient temperature control is required.

Advantages

The straight configuration offers a compact footprint and straightforward installation on radiator or convector inlet pipes. A Kv 0.55 flow coefficient provides predictable flow control suited to typical room heating circuits. Being supplied without a preset allows installers to set balancing and flow rates on site to match system requirements. The valve is manufactured to industry norms for hydronic components and is compatible with standard thermostatic heads for automatic temperature regulation.

Suitable for

• Residential radiator heating systems
• Light commercial heating circuits
• Replacement of existing straight thermostatic valves with 1/2" connection
• Applications where compact thermostatic control is required

Key specifications

• Connection size: 1/2" (straight inline)
• Flow coefficient (Kv): 0.55 m3/h
• Type: Thermostatic straight valve (delivered without presetting)
• Compatibility: Designed for use with standard thermostatic heads for temperature control
• Application: Hydronic radiator and convector circuits

How to use

Install the valve in the return or supply line to the radiator or convector using the 1/2" connection, observing correct flow direction and sealing practice. Fit a compatible thermostatic head on the valve spindle to provide automatic temperature regulation. If balancing is required, set the desired flow by adjusting the presetting mechanism after installation; this model is supplied without preset so initial adjustment must be performed on site. Commission the circuit by purging air, checking for leaks, and verifying that the thermostat head and valve respond correctly to setpoint changes.

Usage recommendations

Use corrosion-resistant fittings and observe manufacturer guidelines for system water quality. When replacing an existing valve, confirm dimensional compatibility and flow requirements. For optimal control, pair the valve with a thermostatic head suited to the room’s heating load and ensure the system is balanced after installation.