I've got a Glow worm 30si system boiler which has been in for 5 years or so. I've had a recent issue that seems to be pointing to the expansion vessel but need to get some expert opinion.
The boiler is failing on low water pressure each time it cools back after a run. I can pressurise the syatem to 1.0 bar ish; it then runs fine and when it's completed heating a couple of hours or so later the pressure is often up aroung 2.4 bar. Overnight as it cools back the pressure falls to below 0.5 and consequently will need recharging again before it can run again.
I've checked the system for leaks and can even isolate the boiler to ascertain where the fault lies. It's clearly the boiler and not the system.
Is this an expansion vessel problem, and if so do I need to change it or is there a repair method? The book says the whole boiler has to come off to get at it, but also states that another vessel of similar spec can be added in as close to the boiler as possible.
Just hoping someone may have some idea as to what's needed. Thanks in advance.
The boiler is failing on low water pressure each time it cools back after a run. I can pressurise the syatem to 1.0 bar ish; it then runs fine and when it's completed heating a couple of hours or so later the pressure is often up aroung 2.4 bar. Overnight as it cools back the pressure falls to below 0.5 and consequently will need recharging again before it can run again.
I've checked the system for leaks and can even isolate the boiler to ascertain where the fault lies. It's clearly the boiler and not the system.
Is this an expansion vessel problem, and if so do I need to change it or is there a repair method? The book says the whole boiler has to come off to get at it, but also states that another vessel of similar spec can be added in as close to the boiler as possible.
Just hoping someone may have some idea as to what's needed. Thanks in advance.