Worcester 24i High Pressure Problems - Expansion Vessel??

[tom2007]

I have a Worcester 24i combi boiler. When in use the pressure increases it to about 3.5 bar after it has been on for about 40 mins, the pressure release value (I think its called that), lets the water out of the system. The boiler is located downstairs, I am ok with hot water downstairs but the upstairs is only getting slightly warm. I have bled the raditors, that has not cured it. I have been advised that I might need to repressure the expansion vessel, has anyone got any ideas on how to do this? Or has anyone got any other ideas?

Would be really grateful for any help on this.

Thanks

 

[EliteHeat]

Remove the schraeder valve cap from the expansion vessel and depress the valve, if water comes out then the vessel is no good - ruptured diaphragm.

If air comes out, or if nothing comes out drain the system and then check the pressure. It should be roughly about 0.6 - 1.0 bar. If significantly different then slowly bring the pressure up. Re-fill and see what happens.

If the pressure seems OK, then suspect a blocked connector to the exp vessel.

It's almost always easier and cheaper to fit a remote exp vessel should yours prove to be damaged or blocked.