BoilerFaultCodesTechnical description
System fault boiler electronics / basic controller
What causes this fault?
This fault occurs when the boiler’s main control board suffers a critical communication failure or an internal electronic crash. It is often caused by a sudden power surge, moisture getting onto the circuitry, or simply a hardware component reaching the end of its functional life. Because the central processor can no longer send or receive signals correctly, the system enters a fail-safe 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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