BoilerFaultCodesTechnical description
Error in parameter settings
What causes this fault?
This fault occurs when the boiler's control board loses the specific software instructions needed to manage the heating process safely. It is typically caused by a data corruption within the internal memory chip or a hardware failure on the main circuit board following a power surge or component aging. Because the boiler no longer knows its own identity or safety limits, 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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