BoilerFaultCodesTechnical description
Internal fault
What causes this fault?
These codes indicate that the boiler's central control board has suffered a critical software or hardware glitch, preventing it from managing the heating process safely. This usually happens because internal components on the circuit board have worn out or been damaged by a power surge, meaning the 'brain' of the boiler can no longer communicate with the sensors and valves. Because the board can no longer guarantee safe operation, it enters a protective shutdown mode.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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