Low
E15 on Ariston Egis 24 MFFI

Your boiler has lost its connection to the outside temperature sensor, which helps it run more efficiently based on the weather.

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 open circuit (where fitted)

Engineer required

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

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Related fault codes

E14View →E16View →

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