We moved into a new house and after bleeding a radiator I now need to increase the boiler pressure. However after looking at lots of videos online, I can't seem to see how I am supposed to do this! We don't have any key provided, and can't see a blue lever like some of the videos suggest. Would be super grateful if anyone could help me figure it out. The photos show the underneath of the boiler and also behind the wooden section below it, that boxes off other boiler bits!