gloworm 30 ci leaking

[tomcorden]

So, got a 9 year old gloworm 3CI boiler, worked fined since installation. Now pressure is dropping on the LCD display. So, If I pressurise to 1.2 bar, drops to <0.7 in around 12 hours. If I run the central heating at full blast, pressure goes to 2.9 bar, constant dripping from the pressure relief pipe (not the condensate one). Can anyone tell me if this is the pressure relief valve or expansion vessel? Any decent heating engineer with experience of glow worm boilers who wants to quote to come and fix it, without fleecing me is welcome to call (07970 382730), Nottingham

tom

 

[ianmcd]

you have an expansion vessel problem , doesnt necessarily need replacing may just need recharged have a look in the info section above its something you can do yourself

 

[tomcorden]

where above can I find this info? Can you post a link please, I cant see it

thanks

 

[sbgasman]

it is in FAQ on P&H

 

[tomcorden]

have pressurised the expansion vessel, no water came out of the valve, there is however some crud (green, powdery exudate) around the bottom of the vessel where the pipe comes out, no sign of any leak at the moment, but clearly something has dribbled out at some point.

external pipe still dripping water, pressure still slowly going down, any advice anyone?

 

[Boilerman2]

Now you have charged your Expansion Vessel, it is likely that the Pressure Relief valve is goosed - it has been discharging regularly and so the seat is probably done for, a new PRV should be fitted, I bet the person who fits will will cut the top of his/her thumb on the sharp bottom frame next to the PRV (I know I always do!! )

 

[tomcorden]

is that easy to do? why will the expansion vessel have lost pressure in the first place?

 

[Boilerman2]

Expansion vessels loose air pressure for exactly the same reason car tyres loose pressure, which is why the expansion vessel MUST be checked annually during the Boiler Service - My engineers check Exp Vessels at any visit i.e. break down or service call it only takes a couple of minuites

The PRV is fairly easy to change, drain the circuit by turning the knob on the PRV, once empty, undo the union nut connecting the discharge pipe, pull this clear, then pull out the clip that holds the PRV into the manifold, twist and pull this clear, (an old towel will be handy to catch any dirty water that might dribble out, fit new valve in reverse order cutting the top of your thumb in the process !!!!

once job completed affix plaster to thumb and have a cuppa

 

[tomcorden]

thanks for the advice, will have a go and keep a plaster ready!

tom