WHEN I TURN ON THE HOT WATER TAP THE FAN GOES BUT THE BOILER DOES NOT FIRE UP THE MANUAL SAYS CHECK AND/OR REPLACE PCB. HOW DO YOU CHECK A PRINTED CIRCUIT BOARD?

CHRIS LOCKWOOD, July 2008

my money would be on a fan/flue related problem
not making the air pressure switch.
if the boiler fires with the combustion cover off,
have your engineer check the fan venturis.

jason, July 2008

could be a number of faults, from asp, to ignition, gas valve, gas pressure, pcb...etc...

no way to 'test' the pcb, ways to rule out all the other possibilities through 'fault logic' then replace pcb is they check out.....

you may change the pcb, suck it and see method!, or get a technician out to 'professionally' retify your problem as you are not permitted to tamper with any of the other possible issues

T, July 2008