Effebi Hexa Spring Check Valve 3/4", Brass, Art. 2301G405

For the 3/4" size, Effebi's table gives a flow coefficient Kv of 8 m³/h, a body diameter of 39 mm and a length of 65 mm. Kv states how many cubic metres of water the valve passes per hour at a reference pressure drop, so use it in a hydraulic calculation rather than as a fixed flow rate.

Effebi gives the 3/4" Hexa a PN 25 rating, which corresponds to 25 bar at 20 °C. The fluid temperature may range from −5 to 110 °C, but the valve is not intended for steam. Before installation, compare these limits with the operating pressure and temperature of your system.

It suits heating water, within its limits: Effebi lists heating systems with radiators, boilers and pumps among its fields of use and allows fluids up to 110 °C. Gas does not appear among the uses Effebi gives for Hexa, and steam is excluded, so fit a valve approved for gas on gas pipework.

The valve opens only when the flow lifts the POM pad off its seat against the spring. Fit it so that the normal flow arrives at the inlet side, for example from a pump outlet, with the outlet facing the part of the system that must not drain back. Both ends have the same G 3/4 female thread, so the connections alone do not show the direction.