BoilerFaultCodesYour boiler's main internal computer or its configuration chip has developed a fault and can no longer communicate correctly with the rest of the system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Control box or the heat control module (HCM) is defective – HCM or control box connections need to be checked
What causes this fault?
This fault occurs when the boiler's main control board loses its memory or fails to establish a secure handshake with the small identification chip plugged into it. It is often caused by an internal electrical short within the circuitry or a loose connection between the module and the main board. Essentially, the boiler has 'forgotten' its own settings and can no longer operate safely.
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 F0262 — 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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