Hi,I have moved house and my radiators are coming on when I select hot water only,I have a drayton ma1 3 way valve/actuator,i have taken the actuator off and the valve spindle moves freely in the valve body,however the actuator will not move to the H hot water only setting,it moves to the middle (both),it will select CH only and the only way I can move the manual lever across to H,hot water only is if I turn the power off and move it by hand,which I can do quite easily,there is no effort needed to slide the lever across. Any help/advice would be greatly appreciated,thanks.