Low
Orange LED on on Sime Friendly

Your boiler is currently in standby mode and is waiting for a command to provide heating or hot water, meaning there is no actual fault.

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

From this model's manual
Verified against the P3 Sime Murelle He System 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.

DIY fix possible

Check if your room thermostat or programmer is turned up and calling for heatEnsure the boiler control knob is set to the summer or winter positionCheck that the external heating controls have working batteries

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