BoilerFaultCodesFerroli A63 Fault Code
The Ferroli A63 fault code means: your boiler's main internal computer has developed a technical fault and can no longer control the heating system safely.. It appears on 4 Ferroli models in our database.
Technical description: Controller ABM03B error – controller internal error
What causes the Ferroli A63 fault?
This fault occurs when the boiler's internal computer chips suffer a hardware failure or a memory corruption, meaning the board can no longer process safety data correctly. The most common reason is electrical degradation of the circuitry over time or a sudden power surge that damages the sensitive components on the PCB.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Ferroli models that show the A63 fault code
Click a model for the full fault code list and model-specific repair notes.
Source
Ferroli A63 fault code information on this page is sourced and cross-checked against the official Ferroli service / installation manuals for each affected model.
Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed 27 April 2026