the hot water and central heating are overheating and shutting the boiler down. when iether are called for on selector. even when thermostat is set low on wall stat for central heating, and the water temp guage on panel set low for hot water.the water temp gets so hot and bangs inside and shuts down gas then the two red lights flash on panel [ c h and h w demand ] they will reset when water temp cools down, but exactly the same happens again . water pressure on guage 1.5 bar but having to regulary top up [ once a month , but we do use boiler constantly ] any ideas gratefully welcome. many thanks.

steve, July 2009

pressure keeps going up, even when i use the relief vale to drain it keeps going up to 3.5 bar thanks wot can i do

mark ramsey, December 2011

Check pump first if still occurs 100% heat exchanger!

Mr Boiler, August 2009

cheers. if i replaced pump and still happens ,any other suggestions, do you think heat exchanger could be blocked ? if so how do i clean it . many thanks steve

steve, July 2009

iffy pump?

a, July 2009