S
samsg30
The boiler you have is made as a heat only boiler, as its probably open vented, it can be fitted to an sealed system if appropriate safety features are added, the f22 fault is probably because you drained it and never bled the boiler or pump etc, have a look in the attic for a small plastic tank that will supply water to the boiler and rads, the f22 fault may also be a temp rise difference within boiler , ( circ problem due to air or lack of bleeding ), hope this helps mate
Looks like you are closing down on the issue... thanks mate. I only bleeded radiators.. don't know where to bleed boiler or pump from? There is definitely a plastic tank in the attic (as pictures posted above). Can you please suggest where to bleed boilder / pump from and is it as straight forward as bleeding radiators or I would be risking something big here.. like leak, permanent failure or massive issue?