Glowworm 24ci High Pressure

[johnnysinc]

I had just taken taken a radiator of the wall to do some decorating. After refitting radiator and filling system I am finding that when I turn the central heating on, the pressure rises from 1.0 Bar to about 3 Bar within seconds it then climbs at about 0.1 bar every second. I then switch it off. The pressure then returns to 1.0 Bar. During this time the radiators are starting to heat up. There is no problem with the DHW side of things.
The boiler is under 2 years old and I have 6 radiators connected to it with 10mm microbore through a manifold system.
I've tried cleaning the filter at the heating return (not very dirty) and made sure the cap on the automatic air vent on top of the pump was undone.
Still the same.
Any help would be greatly appreciated.

 

[gasandoilman]

You should check your presure vessel presure and re pressure if required

 

[johnnysinc]

Thanks for the quick response.
How would I go about doing this on my boiler? It looks like the pressure vessel is pretty inaccessable. Do I need any specialist tools or gauges?
Is there any particular reason this would have happened as I've drained the system several times in the past without problems?
Thanks again.

 

[Agile]

Look at the FAQ on this site for details.

The fault was probably masked by air in the rads!

It is usually only noticed after a bout of radiator bleeding.

Tony

 

[johnnysinc]

Thanks folks. A few pumps into the pressure vessel sorted it. For anyone interested the valve is accessed on top of the boiler near the flue. You don't even need to take covers off.