Expansion Vessel

[Eppilott]

Hi,

Why would an expansion vessel keep deflating?

I have a Worcester 24LE combi where pressure was going over 3 bar.

Engineer came out, checked the EV and pumped it back up.

Everything fine for a few days then pressure starting going over 3 bar again.

I pumped EV back up but same thing seems to be happening again. No water is coming out of the valve so I was wondering why it would deflate.

Cheers.

 

[neiltheplumber]

Could be the schraeder valve or the bladder itself. If its been recharged twice recently then it could be new vessel time. Sometimes you can replace the valve and bladder but its probably wise to just stick a new vessel in.

 

[J_N30]

Its quite rare that the expansion vessels burst. Is it definatly flat?

 

[Eppilott]

Yes, it seems to be gradually deflating. i.e. over the course of a few days, when the CH comes on, it creeps closer and closer to 3 bar.

 

[ianmcd]

Most definately the Shraeder valve passing if the expansion vessel has gone you wouldnt be able to charge it, you can get replacement valve inserts for pennys from Halfords with the key for changing them

 

[dcawkwell]

Because your engineer is a numpty who didn't check the tyre valve.
I always check them with washing liquid and quite often it is this that has started leaking.
Simple to replace and available at most car accessory shops.
Access can sometimes be a problem.

 

[Agile]

Did you pressurise the EXV in accordance with the "best advice" ?

Did you let ALL the air out first with the system pressurised?

Did you ressurise with the system pressure kept at zero?

What air pressure did you leave it at?

Tony