High
E33 on Ariston Clas One

Your boiler has detected that the internal components responsible for venting waste gases are not working correctly, causing the system to stop 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

Fan error. Check the fan cable, replace the fan, or replace the main P.C.B.

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

E34View →607View →6P1View →

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