Low Information
UF on Ideal Logic Combi ESP1

Your boiler is currently in a manual testing or service mode used by engineers and is not actually reporting a breakage or 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.

Technical description

Service Mode / Sequence indicator following SH

What causes this fault?

This code appears when the boiler has been manually put into a specific testing mode, typically by an engineer during a service or installation. It indicates that the system is running at a fixed rate to check performance rather than responding to your thermostat. It is not caused by a mechanical failure, but rather by the control dial being left in a certain position or a button sequence being activated.

DIY fix possible

Wait 5 to 15 minutes for the boiler to automatically exit the service modeRotate the main mode dial back to the 'Off' position and then back to 'On/Winter'Press the 'Reset' button once to clear the display

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