High
ALL 15 on Sime Murelle EV HE 25 Combi

Your boiler has detected an issue with the internal fan that safely pushes waste gases out of your home, so it has temporarily stopped working to keep you safe.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

FAN ERROR 15: If the fan speed is not within the rated speed range, the display will show "ALL 15".

From this model's manual
Verified against the Sime/Sime Murelle Ev He Combi installation & service manual.
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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

ALL 04View →ALL 06View →

All 22 fault codes on the Murelle EV HE 25 Combi

Seeing a different code? Every code this model can display, in one place.

ALL 02ALL 03ALL 04ALL 05ALL 06ALL 07ALL 08ALL 09ALL 14ALL 20ALL 21ALL 22ALL 23ALL 24ALL 25ALL 26ALL 27ALL 28ALL 29ERROR 10ERROR 13

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