High
A03 on Ariston Bravo 24 MFFI

Your boiler has tried multiple times to start but failed to produce a flame, so it has safely shut itself down to prevent a gas buildup.

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 this [E04 attempts], should the boiler still not sense a flame, error code A03 will appear on the LCD.

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

E04View →

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