Calefactio - HGSV12 - Service Valve - 1/2” FNPT

This service valve links the expansion tank to the system or to the Service Center (#HGSC-MULTI) and allows you to isolate the expansion tank from the system pressure. While the tank is shut off from the system pressure, you can inspect it (verify pressure) or remove it for replacement without having to drain the system. Once this operation is over, re-open the valve and the system will get back to normal operation. 

Assembly:

The service valve is delivered “open” with a sealed ball bearing valve. The valve may be mounted directly on the tank connection. Seal the connection between the assembly and the expansion tank.

Expansion Tank Maintenance:

• Unscrew the cap and connect the drain conduit
• (hose) with the threaded ¾ ’’(GHT) connection
• at the Service Valve drainage point.
• Remove the handle’s screw (2.1), remove the
• handle and reinstall after a 180° rotation (2.2).
• Turn the handle 90° (clockwise) in order to isolate
• and drain the expansion tank.
• Once drained, verify the tank pressure. If the
• pressure is too low, reinflate or replace the tank.
• Reopen the valve by turning the handle 90°
• (counterclockwise).
• Unscrew the handle, remove and reinstall after a
• 180° rotation. This operation will fasten the handle.
• Remove the drain conduit and screw the cap
• back on.