Low
Orange LED on on Sime Format System HE

Your boiler is currently in standby mode and is waiting for a signal 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 that your room thermostat is turned upEnsure your heating programmer or timer is set to 'On'Check that the main boiler selector switch is set to the correct heating or hot water position

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Green LED onView →Red LED onView →

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