Glowworm 30si discharge safety valve

[raydocks]

water is escaping from the discharge safety valve when central heating is put on. The boiler worked perfectly during summer when HW only? any ideas how to clear problem?

 

[Plucky]

expansion vessel has gone by sound of it. Needs new vessel in boiler or an auxillary vessel fitted elsewhere in system

 

[raydocks]

Thanks very much, you were right. I have pumped up the expansion tank to about 3 bar and things appear to be working correctly.

 

[Puddle]

Well before you start ripping the expansion vessel out ,you could try re priming it,also the glowworm has a common fault were the small tube connecting the expansion vessel to the main boiler section gets blocked up and requires cleaning out
ps presure in expansion vessel wants to be around 1.2..1.5 bar,if you have pressurised to 3 bar let some out

 

[raydocks]

Well before you start ripping the expansion vessel out ,you could try re priming it,also the glowworm has a common fault were the small tube connecting the expansion vessel to the main boiler section gets blocked up and requires cleaning out
ps presure in expansion vessel wants to be around 1.2..1.5 bar,if you have pressurised to 3 bar let some out

Thanks my system is unvented and has an external expansion vessel for the hot water which i thought caused the problem. I shall now clean that small pipe to the integral expansion tank. Thanks for your help, i just keep topping up the sealed system with water, daily, and it works. not the best thing i suspect?

Thanks for your reply, my system is sealed and has an unvented hot water system with an associated expansion tank which i thought was the proble. i shall now try and drain the boiler and clean that small pipe.