I re-pressurised my expansion tank about 18 months ago using instructions below:-

1. Switch off the boiler. Ensure that there is no water pressure in the system.
2. On top of the expansion vessel (grey object with standard tyre valve on top, viewable from the top of the boiler) inflate with a bike or car pump to 1.5 bar (22 psi)
3. Charge your water system pressure to 1.0 to 1.5 bar.
4. Start your boiler

I've no problems, until this week, found i'm losing pressure again, I tried the above again but found the expansion vessel still around 1.2 bar... Any ideas? when I top the boiler up it runs at about 2.5 bar and empties when off, but does not seem to be coming out of the release pipe at the back as it did 18 months ago. Any ideas??

Chris J, October 2009

I think your EV pressure is a bit high.....usually 10 psi is about right unless the manufacturer says otherwise. If your pressure is constantly dropping, it does mean a leak somewhere.

John, October 2009

i m not sure but seems like u have a leak somewhere either on the rads or the pipe work good luck

sajeed, October 2009