High
4 1 1 on Ariston HS Premium

Your boiler's internal safety sensor, which monitors the combustion process, is failing to communicate with the control board, causing the system to lock out for safety reasons.

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

Camera sensor 1 unavailable

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

5 0 1View →5 0 4View →

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