Boiler Problem - pressure dropping

[scholesy]

I have a Glow Worm - Swiftflow 75/80 (not sure which?).

My problems began a few days ago when I decided to bleed all the radiators to make sure they were all filled properly. I had also heard bubbling noises as the heating system started up which made me suspect air had got in.

All the radiators seemed OK apart from my bedroom one. This let out a lot of air. In fact I had to put 1 bar pressure back into the system followed by a further 1 bar before all the air was expelled.

Now before this the system would rest at around 1 bar and when the heating was on would rise to around 2 bars. Now when the heating comes on the pressure rises to 3 bars at which point the Pressure Release Valve begins to expel water through the drainage pipe until the pressure is around the 2 bar mark. Then when the system goes off the pressure drops from 2 bar to nearly nothing!! The pressure is then that low that the system won't start again until some additional water\pressure is put back into the system.

Any help very much appreciated

Thanks

 

[twgas]

exp ves needs repressurising see FAQs

 

[scholesy]

Thanks Twags for the very quick response. I'll look into that. Cheers

 

[scholesy]

I have read through the FAQ, (and it seems extremely helpful). It says I’ll need to drain water using the ‘Drain Cock’, whereabouts is the drain cock?

Also it seems I may need to buy a few new valves. Is it difficult\expensive to replace the Pressure Relief Valve and also the Pressure Vessel Fill Valve? Once the PRV has expelled water will it defiantly need replacing?

thanks