BoilerFaultCodesYour boiler's internal computer chip is either missing or has failed, meaning the system doesn't know which specific model it's supposed to be.
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 – the code plug needs replacing
What causes this fault?
This fault occurs when the boiler's memory chip, which holds the specific instructions for your model, is either damaged or has become loose. Without this physical plug being correctly identified by the control board, the boiler cannot safely operate and will shut down to prevent damage. The most common reason is a hardware failure within the plug itself or a communication error starting in the main circuit board.
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 2946 V — no call-out fees, no surprises.
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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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