Three port valves are suitable for providing separate heating and hot water circuits. There are two types of 3 port valves, one type only diverts the flow of water whilst the other provides a mid position, providing shared flow to both heating and hot water.

Auxiliary switches on the motorises valve should be wired to switch the boiler/pump on and then off when there is no demand for heating or hot water, providing boiler interlock and complying to building regulations.