my hot water went off and my boiler was not fireing up that is why i changed the diafram would this be the only cause

colin, January 2009

More than likely.If you look there is a pin that goes thro the diaphragm housing to the gas section.Sometimes the pin sticks,but the diaphragm is the number one fault as they perish.Stick at it mate.They are hard to do but all of a sudden you will get it right.

Tony S, January 2009