We have Britony combi boiler and just recently the boiler has been venting 
water out of the relief pipe outside, I have to top up the pressure each 
day, (down to .5 bar), the radiators also occasionally make a bubbling noise 
and seem to be a lot hotter than normal, we also have a problem maintaining 
hot water to our shower, it appears to be some sort of temperature control 
fault, can anybody help.


TIA  Roy