Low
EE 3311 on Ariston Microsystem 15

Your boiler is receiving an incorrect signal from its external temperature sensor, which usually means the wiring connected to the small box on your outside wall has been damaged or has become loose.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

Technical description

Outdoor sensor in short circuit

Engineer required

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

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