ok, firstly, we all know this, and the main thing that burns out on all these boards are mini-relays. BUT and its a big BUT, your safety relies on these pcbs working correctly and shutting down your boiler in a safe manner when nessesary.
If you feel capable and able to repair your own, off you go and do it, but as a 'qualified service engineer' I will tell you and anybody else to throw it away and replace with new, as anything else would be putting people at risk.
T, May 2008
