New Glow Worm 30CXI Combi boiler fitted end Sept 2006 since when pressure dropping has been problem. Piping system has been isolated from boiler and checked with pressure of 5 - no loss in 24 hours. Pressure Relief valve replaced - pressure sensor replaced to no avail. Pressure now dropping in less than a week - result boiler switches off. Plumber (CORGI) and manufacturer both coming up with no answer as yet - Warranty runs out Sept 2008.

Wendy Fruin, January 2008

It sounds like the boiler heat exchanger is leaking...you can't really tell by looking because when water escapes it turns to steam. Time to call them back, and suggest they extend your warranty if they can't sort it!

John, January 2008