protherm 80e?

hi
we have a protherm 80e combi boiler it's about 10 years since we got it. It runs 12 radiators, the problem it at times it cuts out. I manage to get it on by pushing on the control panel. I think it might be an electrical fault but don't know if it is worth fixing. I can't really afford a new one. Also the the pressure gauge keeps dropping.