High
AA 7777 on Ariston Clas One

Your boiler has detected that the internal system used to drain away water produced during heating is not working correctly, causing the system to stop for 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

Condensate Trap full of water Condensate sensor short circuited Condensate sensor in open circuit

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

A04View →1P1View →1P2View →

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