BoilerFaultCodesYour boiler's internal computer is having trouble communicating with its identity chip, meaning it doesn't recognize its own settings.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Coding plug not detected.
What causes this fault?
This fault occurs when the boiler's main control board loses its connection to a small electronic chip that tells the unit exactly how to operate. The most common reason is a loose connection or a component failure on the circuit board, often caused by natural vibrations or moisture getting into the internal components over time.
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.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like b1 — no call-out fees, no surprises.
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Worcester Bosch Greenstar 30HE 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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