Glow Worm 24ci leaking from pressure relief valve.

[Stubzz]

I'm having weird problems with the above boiler. In short whenever it's used water starts draining from the pressure relief valve until i's gets to about 0.6 bar. However the actual pressure never even goes above 2 bar (the valve being rated at 3 bar).

Some random things I've found through playing around:

I've changed the valve and both valves has exactly the same problems.

The valve itself doesn't leak unless the boiler has been used, for instance once I've refilled the system it'll happily sit there and not leak anything all day long so it's not even a constant problem.

When the heating is off it empty's faster. For instance we can have the heating on for several hours and it'll work until turned off; use the heating for only an hour and it'll empty itself within 10minutes once turned off.


Anyone got any ideas what could be wrong?

 

[45yearsagasman]

Expansion vessel precharge is lost or vessel is damaged.If you are not sure of what to do see FAQ's for info.

 

[Stubzz]

Thanks for the reply. We've had the expansion vessel changed a few weeks back so it should be fine but I'll get someone to double check. Any other ideas?

 

[45yearsagasman]

It may be the connecting pipe to the exp vessel is blocked.My money is on exp vessel problem of some kind.All that needs to be checked and come back.

 

[Agile]

Some nupties change expansion vessel without checking/setting the air pressure.

I went to a Puma on a BG contract and they had added an external EXV ( because the communication pipe on the boiler was blocked ).

Thye only problem is that they did not reset the 3 Bar air pressure that it was supplied with. Consequently it had no effect at all.

Its easy to set but the method in the FAQ must be followed.

Tony