High
ALL 28 on Sime Murelle Elite HE Combi

Your boiler has detected a configuration error with its internal settings or electronic system, preventing it from operating correctly.

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

COMPATIBILITY INPUT (S3) ANOMALY ONLY FOR SYSTEM 7

Shared across the Murelle Elite HE range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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 29View →

All 21 fault codes on the Murelle Elite HE Combi

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

ALL 02ALL 03ALL 04ALL 05ALL 06ALL 07ALL 08ALL 09ALL 10ALL 14ALL 15ALL 20ALL 21ALL 22ALL 23ALL 24ALL 25ALL 26ALL 27ALL 29

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