I've got an issue that has recently developed in my HW/CH system..
In order to get my boiler to turn on for the hot water, on the controller I must switch the HW to on, then switch the CH heating on & then off. Once I do this the boiler will fire. Could this be the 3 port valve sticking?
In order to get my boiler to turn on for the hot water, on the controller I must switch the HW to on, then switch the CH heating on & then off. Once I do this the boiler will fire. Could this be the 3 port valve sticking?