hi wonder if any one can shed light on this prob please got a glowworm combi boiler a plumber came to service it a few months ago now and we had a loud gushing noise when we had the hot taps runnig so hes turned the water pressure valve up or down the noise has gone but now we got no hot water upsatairs its only luke warm but its hot down stairs so he says we need something fitting to boiler cant remember the name of it what he said to make us have the same pressure and get hot water upstairs does this sound right