BoilerFaultCodesYour boiler has detected an internal communication error with its memory chip, which is preventing the system from running correctly.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Remove and replace with new code plug (11)
What causes this fault?
This fault occurs when the boiler's main control board loses its connection with the small memory chip that stores the appliance's specific settings. The most common reason is a physical failure of the chip itself or loose internal wiring that prevents the computer from reading the boiler's identity.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like A7 — no call-out fees, no surprises.
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Worcester Bosch Highflow 400 BF is discontinued — time for a new one?
Parts for discontinued models can be hard to find and expensive. A new A-rated boiler could save you money on both repairs and energy bills.
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