I have a conventional Saunier Duval boiler that is approx 14yrs old, it is set on a daily program to come on in a morning and an evening, the morning setting is fine (its only on for around 40mins), the evening setting is timed to come on at 5pm - 9pm but by around 6.20 the radiators are going cold despite the lights on the timer showing it should still be on, to get the heating back on we have to switch everything off from the fuseboard up and restart manually, this does not always work.
I have recently changed the room stat and the timer but the problem remains, any clues?
I have recently changed the room stat and the timer but the problem remains, any clues?