How do i get the pressure gauge to rise i've lost my manual , the needle is lower than it should be any experts out there that can help me out on this one?
You need to find the filler loop, which is usually a piece of (flexible) tubing with an inline tap valve, often close to the pressure gauge. You turn the tap on slowly and you will hear cold water flowing from the cold water system into the closed (pressurised) circuit. The dial rises. Stop when it reaches one bar on the gauge.
If the gauge keeps falling back (say over the next month) you need to call in a plumber because it means water is escaping from the pressurised system somewhere.
If you cant find the filling loop as buildersmate advised. Then it may be that a few worcester bosch boilers had a built in filler under the boiler there is a grey plastic handle that has to be inserted into the hole there and turned through 90 dgree to line the return with the mains and open the valves till you hit 1 bar then turn off again.