I am having a problem with the motorised valve on my Worcester 15/19 heatslave boiler. I always seem to have hot water but the heating does not always come on,also for no apparent reason the radiators get very warm for a short periob with the boiler not firing(usually after running the hot tap. If I move the manual lever on the back of the valve to manual lock it is against resistance and the radiators heat up. When releasing the lever it only moves back to about 50% of the slot, if I move it to the end of the slot it feels as if it is disconnected, there is no resistance. Should the lever move to the end of the slot? Also should I be able to see the lever move when heating or ch is required. A new PCB has been fitted but the problem still persists.
Any help would be gratefully received