High
A03 on Ariston Euro Prisma 24

Your boiler has failed to ignite the flame reliably and has stopped trying for your safety.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

Technical description

After attempting to relight two more times (20 seconds between each attempt), the boiler still does not sense a flame.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

A01View →A02View →

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