We’ve got a Worcester Bosch heatslave oil boiler, and I think its CH thermostat is a bit knackered.
In the past we’ve hardly ever had to set the boilers heating control higher than 1 or 2 as the house doesn’t get that cold, but lately we find we’ve got to keep turning the heating control up quite a long way before it click’s on, usually to around 3. The boiler then fires and works ok and gets up to the temperature set on our room stat, but sometimes it stops before the room stats set temperature and you have to move the temperature control up even higher before it clicks on again. Today it didn’t even click on when I set it to its maximum setting. Also the control knob does seem a bit stiff to turn, certainly when compared to the water control.
By my description do you think that the likely fault?
