Medium
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.

What the manual says

Manufacturer manual

Display shows oF after pressing RESTART (PCB programming mode)

Shared across the Logic Combi range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s 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 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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Related fault codes

F1View →L2View →

All 34 fault codes on the Logic Combi ESP1

Seeing a different code? Every code this model can display, in one place.

00DUF1F2F2 or Fn or LnF3F4F4 or L4F5F5 or L5F6F7F8F9F9 or L9 or F8 or L8FAFnFUL1L2L4L4 or F4L5L5 or F5L6L8L9LCLnSHSLUFuP

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