Hi everyone. First time on this site. I would appreciate an heads up from someone in the know. More atune to working on greenstar boilers, i have a customer with a Main 24he combi showing no sign of firing up on heating or hot water. I have the air pressure switch in mind and possibly a PCB problem. What I would like clarifying is the power light flashing every 2 seconds or so. Does this relate to a particular fault problem. All the best.