My central heating gives hot water , however when central heating is called the valve does not move over to the CH position . I have to manually move the lever across and then the heating starts to come on . I can then control the heating via the room stat . When the roomstat is turned down the heating switches off and the 3 port valve then moves to the HW position and then the performance starts all over again when I need heat . I removed the head from the valve body , there is no signs of leaking but when I put a small spanner on the spindle to turn it there is very little movement . I'm not sure how much movement to expect and don't want to force anything . The make is by Heating and plumbing ltd and the model is IXION . I am prepared to fit a new complete valve if need be . Your advice would be most welcome put the kettle on