High
E33 on Ariston Bravo 24 MFFI

Your boiler has stopped heating your home or water because it is not receiving a signal from your underfloor heating temperature sensor.

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 →

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