BoilerFaultCodesYour boiler has stopped working because its internal computer board is either the wrong version for this model or has been configured incorrectly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Incorrect PCB fitted
What causes this fault?
This fault occurs when the boiler's main control board is unable to identify the specific model it is installed in. It most commonly happens after a repair where a new circuit board has been fitted but the specific software key has not been inserted, or if a technician has accidentally programmed the wrong settings into the system.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like 28 — no call-out fees, no surprises.
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