BoilerFaultCodesYour boiler has detected an internal electronics failure that is preventing it from safely lighting the gas to heat your home.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Automatic gas igniter Asic fault code
What causes this fault?
This fault occurs when the boiler's main control board fails to communicate correctly with the ignition system, meaning it cannot verify that it is safe to light the flame. It is usually caused by a physical hardware failure within the electronic circuitry or a degraded ignition lead that can no longer carry the necessary electrical signal. Essentially, the boiler's 'brain' has detected an internal error that prevents it from managing the gas supply securely.
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 9.3 — no call-out fees, no surprises.
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