No ignition of boiler either by hotwater or heating, when switch on the trip light is on when the boiler starts i can reset trip but after 15-20sec it the trip light illuminates, all fans start but no flame. Similar problem last year but changed the black box that controls the ignition and all worked, refitted another working ignition unit but still same problem.

Brian, May 2008

Yes it was the gas valve, thanks the check list.

scubyo, June 2008

Yes the fans spin up fast once demand is on so i will check as suggested

Brian, May 2008

basically its either, a problem with the fan not getting to speed, the aps-flue-ventrui-aps pipes, the ignitors, the gas valve, the pcb........kinda have to check everything one by one that operate in the sequence from the fan forward .....

T, May 2008