Thanks
sorry new to this i am an able diy'er and happy to do plumbing and electrical work
is the heat exchanger something that i can do myself, ie unblock or replace or do i need an engineer to sort this
MY BOILER LIGHTS UP FOR A SHORT TIME THEN GOES OFF THEN RESTARTS ABOUT 20 SECONDS LATER RESULTING IN THE HOT WATER GOING FROM HOT TO COLD BUT THE RADS STILL HEAT UP THOUGH javascript:emoticon(':cry:')