First post, been advised to ask on here by friends.
We live in a maisonette. Kitchen and living room on first floor, bedrooms and bathroom on 2nd floor.
We have a Vokera combi boiler which was put in in 1998 when we moved in. This has been fine, it gets serviced every year and has had the heat exchanger replaced about 5 years ago (hard water area).
We had the bathroom done in 2007 using parts from bathstore. Installation was done by a bathroom fitter (basically a joiner/builder we know who is good at bathrooms).
All has been fine really but never been 100% happy with the thermostatic shower. It's never seemed to have much temperature range but other than that fine.
Had the boiler serviced last year (by a heating engineer, gas safe registered etc) and straight away it was like there was no heat adjustment at all on the shower. You could have a good shower but then the water temp was too cold to run a bath. Turn up the heat on the boiler to make the bath better and the shower was too hot (literally scalding). Spoke to the heating engineer, said he doesn't do showers, speak to a pumber.
Got a plumber in before christms, gas safe registered. He had a look and said the bathroom taps and shower were plumbed in wrong (hot going into cold side and vice versa). Also mentioned poor flow rates in upper taps (previous to this place I lived in London with RUBBISH water pressure). Basically on the bath taps the cold runs about three times as much as the hot (not measured it properly). He suggested replacing the boiler (on the basis of poor flow) then looking into the shower problem. He said he would come back but not heard from him, not chased him as haven't got money to replace boiler unless it needs doing. He mentioned that cold water feed might need sorting (possiblity of one feed from street feeding 2 or 3 flats).
Still got the same water temp problem.
I'm not 100% convinced boiler is to blame, if it's on it's way out then how can it run 8 radiators and heat tap water as hot as you want?
So I am stuck.
Do I replace the boiler in the hope it solves the problem? Or get the shower sorted and then look at the boiler if that doesn't work? Or get a new cold feed sorted (with the possiblity of a new cold feed to a power shower in the bathroom - which would leave the boiler doing heating and bath water).
I'm happy to do any flow rate tests people suggest. I've got the manuals if anyone needs any figures to help give me more advice.
It's my understanding that if the thermostatic valve is plumbed in backwards with a big different in flow rates then it won't work properly, is this right?
Thanks in advance.
