I have a glow worm 100e combi boiler. This has a leak underneath where the thermosatat is. Any ideas on what this could be and how much it will cost to repair:

Francis, September 2010

I had a leak on mine a while ago. It turned out to be the diverter valve. There us a pin that comes through the casing to to push a switch. The leak was around the pin. If you replace the diaphragm to start with. Should cos a couple of quid. If that doesnt work the valve mechenism next. Not expensive at all.

Kaz, January 2011