High
ALL 29 on Sime Murelle Elite HE 35T System

Your boiler's internal computer is struggling to communicate with its own internal components, meaning it has shut down as a safety precaution.

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

NUMBER OF CONNECTED BOARDS ERROR

From this model's manual
Verified against the Sime Murelle Elite He Combi installation & service manual, page 33.
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 28View →ALL 30View →

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