BoilerFaultCodesTechnical description
Calibration required
What causes this fault?
This fault occurs when the boiler's internal computer loses track of the precise balance between gas and air needed for a clean flame. It often happens after a power cut, a sudden change in gas pressure, or if the internal components have worn slightly over time, causing the system to lose its 'fine-tuning'.
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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