Make sure you don't raise the pressure above 1. In normal use, the pressure may rise to about 2, 2.5 and this is OK. Any higher is not good.
The valve for raising the pressure on my 80SP is underneath the boiler on the right hand side and looks like a white tap head. In order to find it I had to remove the surround that had been put under the boiler for cosmetic reasons.
According to British Gas, these boilers are still fine to keep (even though they may not make them any more) but longer term you should think of changing over to a new boiler (i.e. in a few years).
Bleeding the radiators will make pressure drop, so try not to do it unless you have to.
Sarah
October 2005