Low
E 15 on Ariston Euro Prisma 24

Your boiler is struggling to read the temperature outside, which is usually due to a loose wire or a damaged sensor cable.

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 (if 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

E 14View →E 16View →

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