Alpha cb24 expansion vessel bar pressure

[smuudge]

Hi, my alpha cb24 is emptying itself using the PRV. I have been told to check the pressure of the expansion vessel at the back. Can anyone tell me what pressure it should be reading? I have put a pressure gauge on it and it appears to be at 2bar..

Thanks

 

[twgas]

You need to open a drain point and check the charge while its still open.
Usually around 1bar.

 

[smuudge]

Thanks. So open a bleed valve on a rad then check the pressure is around 1 bar?

If the pressure is ok any idea what else could be causing the boiler to let go? Basically the pressure gauge on the front of the boiler goes into the red every time it is on and in turn the PRV dumps water then we have to refill and so on.....

 

[bazdaman]

Its either the vessel flat or a blockage in the communication tube/flex

 

[twgas]

It will take forever using a bleed valve, connect a hose to a drain cock......
Although, I think, there's a drain point on the boiler, if its accessible put a bucket under it.......

 

[smuudge]

Pressure now at 1 bar on the expansion vessel. Running the boiler as we speak to see how it runs...

 

[smuudge]

Thanks guys. Appears to be holding pressure steadily during heating.