Low
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.

What the manual says

Manufacturer manual

To run the burner at maximum rate

From this model's manual
Verified against the Ideal Logic Max Combi 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.

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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