I have a Worcester 350 combi which I have to pressurize it to about half a bar before it fires up, been told that the expansion tank bladder is gone(needs replacing) or deflated and needs recharging(when I press in the tyre type valve on the expansion tank,water comes out and also water dripping from the downstream of the 3 bar relief valve to the drain outside the house).
If the bladder is deflated,what do I use to inflate it air or Nitrogen(in my job, we use Nitrogen gas to inflate bladders) and to what pressure?
Is changing the bladder a major job?

Bruce Eghtedari, February 2008

Hi Bruce,

Yeah the expansion vessel has had it alright. But you can avoid the hassel of removing the boiler from the wall if you have somewhere else on the system that you can put a suitable expansion vessel (needs to be properly sited though)
but most times is a cheaper solution that replacing the one in the boiler.

AG, February 2008

no point inflaiting it as you have been told it's knackered.
and you have proved that by saying water is comming out of it. so it won't inflait.
major job boiler off the wall and you have to be corgi to do it.

sonray heating, February 2008