Medium Lockout
oF on Ideal Logic Combi ESP1

Your boiler is currently stuck in a technical programming mode used by engineers and is not currently in its normal operating state.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

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This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.

Technical description

Display shows oF after pressing RESTART (PCB programming mode)

What causes this fault?

This issue occurs when the boiler's internal computer gets stuck in a setup mode used by engineers to program the software. It usually happens if the restart button was held down too long or if the control knobs are damaged, preventing the system from switching back to its normal heating mode.

DIY fix possible

Press and hold the 'RESTART' button for 2 secondsOnce the display changes, rotate the mode knob (the one with the sun/snowflake icons) to 'OFF'Wait 5 seconds, then rotate the knob back to your desired 'Heating and Hot Water' setting

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