Low
Orange LED on on Sime Format HE Combi

Your boiler is currently in standby mode and is waiting for a command from your thermostat to provide 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

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 that your room thermostat is turned up higher than the current room temperatureEnsure any external timers or programmers are set to 'On' or 'Auto'Verify that the main selector switch on the boiler is set to the correct heating or hot water position

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