Just replaced the pressure release valve and set system to 1.5bar to manual, checked the pressure vessel and pressure in side is 0.75 but still when the system is running it flashes 3.0bar.
When the system is cool the gauge goes to 0.9bar , if andone can tell me the procedure to check the system would be great.
Thanks for your replys in advance.

andy, December 2009

check the expantion vessel with the presure in the rads at 0 bar

b, December 2009