When the central heating is in "off" mode, the boiler will kick in every 12 hrs to raise the water pressure. This makes a bang that is quite disturbing and we worry what damage it could be doing. What can I do about it other than keep the heating on 24/7 ?

george, October 2010

the ignition electrode needs to be replaced along with the ionisation probes in the heat exchanger.you are getting what is called explosive ignition due to a poor spark and a build up of gas in the heat ex.

deano, October 2010