BoilerFaultCodesYour boiler's computer memory chip is not being recognised or is mismatched, which prevents the system from starting up.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Incorrect code plug detected
What causes this fault?
This fault occurs when the boiler's internal memory chip, which stores the specific settings for your model, fails to communicate with the main control board. The most common reason is that the chip has worked loose, become corrupted by an electrical surge, or was incorrectly installed during a recent repair. Because the boiler no longer knows its own technical specifications, it shuts down as a safety precaution.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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Could it be time for a new boiler?
If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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