I have a wall mounted central heating boiler (oil fired) that was fitted just over two years ago. Just lately it has not been shutting down.
What is happening is when the system should be off on the timer she still fires occasionally. i have had the engineers in and they say the boiler is fine and that the motoriised valve is at fault. This has been replaced and still the problem exsists.
Could either the room or cylinder thermostat be at fault and still calling for power. The hot water gets very hot and when only the water is on the radiators get warm. They work normally when set to heating. The system is a fully pumped system that has not given me any trouble until now.
Would be very greatful you can cast any light on the problem.