Hi new to site wondered if anyone can help? I have a microgenus combi boiler that loses pressure at a very rapid rate (less than 2 weeks) I've checked all the pipe work I can including outside overflow from boiler and cant see any leaks, I have two radiators upstairs that seem to fill with air before any of the others, they are I believe at the end of the run from the boiler, everything else works fine, i top up pressure and all is ok again but it seems scary how much water sounds like is going in (where is it disappearing to?