We've had a Mira Discovery Concentric Exposed Valve for a few months now. When it was originally fitted it ran off an old combi boiler and although the shower was new it would heat up and then go cold 3 or 4 times each shower, and each time it went cold the water power would increase and then slow again once the heat returned.
Thinking the problem was with the boiler, we've had a new 33kw vailant boiler fitted a month ago. The problem has reduced but not been solved completely. Now the shower may go cold only 1 or 2 times a shower.
Has anyone else had this problem, or any idea how to solve it?
(Original shower installer no longer lives in our region otherwise I would have asked him back.)