My potterton heating system is on a timer but it wont now swith off. The timer controls are working correctly. I have had to switch it off at the bolier. Does any one have any idea why?
it will have y plan or zone valves fitted on heating system which have switches inside which stick in the on posisition telling boiler to fire even when there is no demand
craig bg
March 2009
Some boilers are installed with a frost-stat (often in a garage) that overrides the programmer - to stop the pipes freezing in cold weather. If you have a frost stat it may be defective - been bumped by something perhaps.