The mechanical thermostat should still click between off and on?
Dont understand sorry,do you mean the room stat? if so yes that clicks
No the thermostat on the boiler does it click when you turn it on/off?
sorry mate,right i have just turned the t/sat on and off a few times, it started clicking as though something was like a valve was opening and closing fast-but then the boiler fired up!!-sorry this make sense?
Yes, if it doesn't click then it will not fire up
It sounds like it is on its way out, but they are still available
just keep an eye on it and replace it if you need to
An easy swap with two electrical connection and a thermostat that sits in a pocket
thanks very much!