BoilerFaultCodesYour boiler's internal computer has developed a fault and can no longer control the heating and hot water functions safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Main board fault
What causes this fault?
This fault occurs when the boiler's central control board suffers an internal electronic failure, preventing it from processing data or sending signals to key components. The most common reasons include a sudden electrical power surge, moisture getting onto the circuitry, or general component wear and tear over many years of use.
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 13 — no call-out fees, no surprises.
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