SAME PROBLEM WITH MY BOILER (locking out) ONLY 13 MONTHS OLD
FOUND MANY BAD SOLDER JOINTS AROUND DIODES WHICH COULD BE FIXED, BUT IT'S IMPOSSIBLE TO FIX BAD JOINTS ON THE SURFACE MOUNTED COMPONENTS ON THE OTHER SIDE OF THE BOARD...
ANSWER ??? BOUGHT NEW BOARD FROM KEEPTHEHEATON.COM FOR
£150...