At least i now know its a vented system. Cant see why a pressure indicator fitted. It must be there to panic and confuse the confused!!! Thank you for your help.. :D
Thanks Kev. I dont really know if its a vented system but are you saying although the pressure indicator reads .5 when cold and drops to o when boiler heating up thats ok?
AAAgh. i have a greenstar 30cdi system boiler with no filling loop and nowhere to stick plastic charging key! my boiler has a pressure guage that is only reading .5 . My builder has told me that the sysem is filled by the small tank in the loft. THAT DOESENT SEEM TO BE RIGHT. Can anyone help?