i have been having such a nightmare with my central heating and its even baffling the so called experts.before christmas i had to have the red cylinder on the immersion heater replaced as it was faulty and within the the week my central heating started playing up...i would advance the heating and it would come on ok but then when i would go to turn the advance button off the heating wouldnt turn off but it would get hotter then it started to not come on at all so i called somebody rom renelec out and i had to have the board changded inside the boiler replaced...all was well again untill the next day...i pressed the advance button and the central heating wouldnt come on...does anybody know whats going on a the proffessionals definitely dont...