expansion vessel is knackered or needs recharging 0.5 bar should read from cold when tested at the valve attached to it if it needs replacing in most cases if its intergral to the boiler it will involve removing boiler from wall etc and installing a new expansion vessel ???
heating doctor January 2008 |
There are three reasons for pressure rising, filling loop bypassing, plate heat exchanger allowing mains water through, or expansion vessel needs recharging.
Hope this helps!
Justin January 2008 |