Unable to re-pressurise boiler

[Tailpond]

I'm trying to repressurise my Potterton Promax Boiler as the pressure reading is fairly low at 1 bar. I've read the instruction manual, which says I need to use the filling loop under the boiler. Unfortunately, there isn't a filling loop on the underside of the boiler and no braid attached either, see photo.
I've looked in the hot water cylinder cupboard where there are three black valves. In the photo attached, valves 1 & 2 are the same type, valve 3 is different. Valves 1 & 3 are on both ends of the braid, valve 1 will turn, valve 3 will not.
I have tried turning just valve 1 but nothing happens. When valve 2 is turned water spray comes out.
Any ideas how I re-pressurise my Boiler?

 

[ShaunCorbs]

3 will open maybe stiff but it will note it will only open one way so have a look

so open 3 all the way then slowly open 1 no more than 1/3 or a turn while keeping an eye on the pressure gauge on your right when it hits around 1.2 shut 1 and then 3

 

[Tailpond]

3 will open maybe stiff but it will note it will only open one way so have a look

so open 3 all the way then slowly open 1 no more than 1/3 or a turn while keeping an eye on the pressure gauge on your right when it hits around 1.2 shut 1 and then 3

Thanks! Worked a treat!