what is the reason for to much presure on my combi wors 28sill?

roughly translated to worcester 28si MKII?????

is it increasing pressure when central heating is used or just always adding pressure whether on or off?

*normal operation on ch eg: cold 1 - 1.5 bar rising to 2 - 2.5 bar with heating on for decent period of time. then when ch ceased and boiler cools it should return to 1 -1.5.
that is normal and expected as water expands when heated

if only when ch is used your guage goes from say 1 bar to 3+bar within couple of minutes and leaks from relief pipe outside, your expansion vessel needs attention: either recharge or replaced.

if all the time whether on or off, the pressure just seems to rise then filling loop may be passing allowing top up of system even though it appears off or worst case scenario heat exchanger maybe pin holed allowing cold mains into sealed system thus increasing pressure

clear as mud eh

iain
July 2008