Low
E15 on Ariston Bravo 24 MFFI

Your boiler is struggling to read the outdoor temperature, likely due to a loose wire or a faulty external 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.

What the manual says

Manufacturer manual

Outdoor sensor open circuit (where fitted)

From this model's manual
Verified against the Ariston Bravo 24 Mffi installation & service manual, page 56.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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