Thanks, could very well be in this heavy limescal area - hubby took out an overflow pipe that was totally scaled up - sent it to the Uni for their course!
Dad-in-law has b & q Silver Star combi LS100T - ch works perfect until turns on taps and water is warm for 30 secs & cuts out - pressure drops in system but water pressure 1.2, so any ideas? :? [/list]