I have a potterton combi boiler. On noticing that the pressure had
fallen slightly below the indicator level I asked a neighbour what to
do (we all have the same system). He showed me how to top it up but
at the same time managed to over pressurise it and it went into the
red zone. He released the pressure again using what he said was a
pressure release valve. Since then the pressure keeps falling and I
am having to top it up every day.

Now I am wishing I never asked for advice. Is there something that I
can do or is it a job for the professionals? It's due for a service
next week but I would rather not have to pay out for a repair when it
maybe something very simple.

Thanks

Angela