Low Information
SH on Ideal Logic Max Combi

Your boiler is currently in a manual testing mode where it runs at full power, usually activated by a technician during a service.

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.

Technical description

To run the burner at maximum rate

What causes this fault?

This code appears when the 'Service Mode' has been manually activated on the control panel, typically by a heating engineer during an inspection. It occurs because the boiler has been instructed to bypass its normal temperature controls to run at maximum output for testing purposes. It is not caused by a mechanical failure, but rather a specific settings choice made on the interface.

DIY fix possible

Press the 'Mode' button to exit the service functionSwitch the boiler off and then back on at the fused spur switchWait for the boiler to complete its start-up sequence

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