BoilerFaultCodesYour boiler's internal computer has encountered a critical error or is not communicating properly, meaning the system cannot run.
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 – control box and connections need checking or HCM might not be inserted properly and need replacing
What causes this fault?
This fault occurs when the boiler's main brain and its specific identity chip fail to communicate or suffer an internal electronic crash. It is usually caused by a loose connection following a recent repair, or the internal circuitry of the control board simply failing due to age. Without this digital handshake, the boiler stays off to prevent it from operating with incorrect safety parameters.
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 F0280 — 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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