BoilerFaultCodesYour boiler’s internal computer chip has encountered a communication error or technical failure, preventing 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: The burner control unit KIM (boiler identification module) has an error. Cabling might have poor contact breaks and pinching or the plug and wiring of the burner control unit needs checking, also check the operating characteristics of the boiler by replacing the burner control unit.
What causes this fault?
This fault occurs when the boiler’s central computer loses its connection with the small identification chip that tells it which model and power setting to use. It is usually caused by a loose connection, damaged wiring, or a complete electronic failure of either the identification module or the main control board. Without this vital data, the boiler stops working as a safety precaution because it no longer knows its own operating limits.
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 F0239 — no call-out fees, no surprises.
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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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