Medium
E 33 on Ariston Euro Combi 30 MFFI

Your boiler has stopped because it thinks a safety switch connected to your underfloor heating has been triggered or disconnected.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Floor heating thermostat open circuit (if fitted) (ROOM THERMOSTATFLOOR)

Engineer required

This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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