High
ALL 29 on Sime Murelle EV HE 25 Combi

Your boiler's main computer is having trouble communicating with its internal electronic boards.

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. When the 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 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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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 15ALL 20ALL 21ALL 22ALL 23ALL 24ALL 25ALL 26ALL 27ALL 28ERROR 10ERROR 13

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