BoilerFaultCodesYour boiler has detected an internal error and has entered a lock-out mode to prevent any further issues.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Appliance fault (see page 22)
What causes this fault?
This fault occurs when the boiler's central control board experiences a communication failure or an internal electronic malfunction. The most common reason is a component failure on the main PCB or a loose connection in the internal wiring harness, which prevents the boiler from safely monitoring its own operations.
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 Ad — no call-out fees, no surprises.
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Worcester Bosch 29 HE Conventional 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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