High
ALL 29 on Sime Murelle Elite HE 35 T ErP System

Your boiler has lost communication with its internal electronic control system, meaning it doesn't recognize its own parts.

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: number of connected boards does not correspond to the number of boards set in the PCB (PAR 40) or there is a failure of communication with it

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 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.

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