Low
Orange LED on on Sime Murelle HE System

Your boiler is currently in standby mode or switched off, which is a normal state when there is no demand for heating or hot water.

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

Stand-by / off — normal stand-by condition

Shared across the Murelle System HE range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

DIY fix possible

Check if your thermostat or programmer is calling for heatEnsure the boiler power switch is in the 'ON' positionCheck that the gas supply is turned on if you have recently had work done

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Related fault codes

Green LED onView →Red LED onView →

All 25 fault codes on the Murelle HE System

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

ALARM 01ALARM 02ALARM 03ALARM 04ALARM 05ALARM 06ALARM 07ALL 02ALL 03ALL 04ALL 05ALL 06ALL 07ALL 08ALL 09ALL 10ALL 13ALL 14Flashing orange LEDLED flashing after fanOrange LED flashingRed LED after flow switchRed LED on (after safety stat)Red LED on (solid)

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