High
3 03 on Ariston Challenger 80E

Your boiler's internal computer is experiencing a communication error and has shut down to prevent potential damage to the system.

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

Main P.C.B. error

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

3 04View →3 05View →3 06View →

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