We have a Thorn M Gas Boiler (M44/54). It has recently had a new thermostat fitted which appears to be working fine.
However before the thermostat was fitted, and since, the boiler hasn't been coming on of a morning despite the programmer for both HW & CH showing that they are on and the pump clearly running. We had the programmer changed but this has had no effect. If you either a) switch the programmer for CH&HW to off then back to twice the boiler fires up or b) you turn the thermostat on the boiler right down until it clicks then switch it back up it also fires.
NEW INFORMATION: If you leave the HW on constant and the CH on once the CH does come on of a morning.
However before the thermostat was fitted, and since, the boiler hasn't been coming on of a morning despite the programmer for both HW & CH showing that they are on and the pump clearly running. We had the programmer changed but this has had no effect. If you either a) switch the programmer for CH&HW to off then back to twice the boiler fires up or b) you turn the thermostat on the boiler right down until it clicks then switch it back up it also fires.
NEW INFORMATION: If you leave the HW on constant and the CH on once the CH does come on of a morning.