problem with boiler - when i demand hot water, the pump will work but sometimes burner will not fire up, sometimes it does and then water goes cold. Central heating will sometimes kick in on timer, sometimes not. most curious though is the pump which turns on and off intermittently for no reason. I hope someone can help ! I have tried the manual fault finder/diagnostic but am unable to identify the pins and their respective numbers to go any further. .

cold andy, December 2010

sounds has if the pump is on the way out undo the chrome nut in the middle of the pump and turn the pump rotor with a small screwdriver it should turn with very little resistance if it binds at any point it needs changing

brian, December 2010