BoilerFaultCodesTechnical description
Internal control unit error
What causes this fault?
This fault occurs when the boiler's electronic brain becomes confused or receives conflicting signals from the sensors that monitor the burner's flame. It typically happens because the main control board has developed an internal electrical flaw or can no longer accurately verify that the gas has ignited safely.
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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