Im sure this is probably a common problem but im a girl and dont know what to do, havent used my water in a couple of days and havent used rads in months but ive got a heatline combi boiler which was only fitted this time last year, and the bar pressure is very low so the boiler has shutdown. I dont know how to get it back up to between 1 - 2. Im sure its a simple thing and I just wondered if anyone could help