I am having some trouble with my tenants in our flat which is a new build (well, it's about 7 years old) and so everything is quite new.
The tenant complains that the shower temp changes while he is showering. I called out the plumber and he said he was 95% sure it was the heat exchanger, particularly since it also sometimes happens in the second shower. They came out as soon as the fault was reported, cleaned the exchanger which was apparently very clogged, tested the shower and said that it was working fine.
Now the tenant says the problem is still happening but the plumber says he has no more solutions. I don't know what to say really - they rightly expect good service but I don't know whether this justifies putting a new shower in.
Does anyone know what it could be?