Not quite sure if this is the correct section for this. My daughter has recently bought her first house. It has central heating & a shower which runs off the combi boiler. The heating seems fine, but when she tries to use the shower, it starts hot & then runs cold after a couple of minutes. Any idea what the problem is here? And what solution can anyone suggest please? Any ideas would be most welcome.
Do other hot water taps display the same symptoms ? If so, then the problem likely is with the boiler. If not, then it may still be the boiler in that the shower flow may be too low in volume for the flow/pressure sensing mechanism to switch on the gas. If the symptom occurs "after a couple of minutes" during continuous flow then one thing worth trying is to turn off the flow and then back on again to see if the boiler again heats up the water. If this works (hot water again) then the above switching is a likely cause.
My son had a similar problem in his first flat, the shower would go hot, cold, hot, cold...
He finally gave up with it and had an electric one installed, problem solved.
A plumber may be along in a while but my pure guess would be that one is using the existing hot in the pipes and then the combi fails to push sufficient newly heated water in after that. In any case my boring solution would be to get the British Gas guy in to check.