High
ALL 28 on Sime Murelle Elite HE 35 T ErP System

Your boiler has detected an incorrect electrical connection or sensor setup inside the unit, which prevents it from operating safely.

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: a probe is connected instead of a clean contact on entry S3

From this model's manual
Verified against the Sime/Sime Murelle Elite He 30 35 35t Erp 6322860 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 01View →ALL 04View →ALL 06View →

All 23 fault codes on the Murelle Elite HE 35 T ErP System

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

ALL 01ALL 02ALL 03ALL 04ALL 05ALL 06ALL 07ALL 08ALL 09ALL 10ALL 13ALL 14ALL 15ALL 20ALL 21ALL 22ALL 23ALL 24ALL 25ALL 26ALL 27ALL 29

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