Adjusting pressure valve on range Tribune he hot water cylinder

Hi,

I have recently moved in to a new house which has a system boiler and a hot water cylinder (previously had combi boiler). The pressure valve is below 1 bar and I have no idea how to change the pressure. I have read through the manual which was no help whatsoever! I have googled it and our system looks different to all other pictures online. I dont seem to have a filling loop tap to turn. I have turned the only black tap I have and that just releases water!
Please help!!
I have added some pictures to help...
Thanks

 

OK its good that you added pics, because your post is completely wrong, your Range Tribune is an unvented Hot water cylinder and has an expansion vessel, the white one in your pics, your Central heating has a different expansion vessel, the red one in your pics, when the CH pressure drops the boiler will cut out for safety reasons,you will have a flexible hose somewhere that you need to attach to the two connections I have shown and open the valves to pressurise your Heating boiler to between 1 and 1.5 Bar

 

Ian, shouldn’t the flexi hose hanging on the right of the picture be connected to the two valves and then both valves be opened until the pressure gets to 1.5bar on the gauge?

 

Thanks for your response both. Which other valve other than the black one needs to be opened?

Sorry I am useless at all this!

 

This one (circled blue)using a flat head screwdriver or similar. Make sure you connect the flexi hose and tighten onto both threads. You may also need to establish why the pressure has dropped.

 

So, remove both caps, connect flexi hose between them and tighten. Open fully the left valve using a screwdriver and turn it 90°. Then, slowly open the right valve and watch the gauge in till the black needle lines up with the red one. Do this when the system is cold. Close off both valves, remove hose, refit caps. That’s the correct way but most people just turn the valves off and leave the hose connected for the next time.