Low
ALL 23 on Sime Murelle EV HE 25 Combi

Your boiler has detected an issue with a temperature sensor connected to an optional second heating zone, though the main system is still running normally.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

DELIVERY PROBE BREAKDOWN ANOMALY SECOND MIXED ZONE: If the delivery probe is open or short circuited the display indicates error ALL 23. During this error the boiler functions normally.

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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

ALL 22View →ALL 24View →

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 24ALL 25ALL 26ALL 27ALL 28ALL 29ERROR 10ERROR 13

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