High
E33 on Ariston Egis 24 MFFI

Your boiler has stopped running because it has detected a safety issue with the floor heating temperature sensor or its wiring.

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

Under floor heating thermostat 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

E34View →E35View →

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