High
F9 on Ideal Logic Max System

Your boiler’s internal control board has lost its configuration or is brand new and hasn't been programmed yet to tell it which model it is.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Call an engineer soon

Book a Gas Safe engineer within 24 to 48 hours. Your boiler may be unsafe or could break down completely if left.

What the manual says

Manufacturer manual

Unprogrammed PCB / PCB replacement mode

From this model's manual
Verified against the Ideal Logic Max System 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 fault occurs when the boiler's central brain loses the specific instructions that tell it how to operate your particular heating system. It is most commonly caused by a power surge that has wiped the memory chip, or it appears after a technician has installed a brand new control board that hasn't been configured yet.

Engineer required

This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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Related fault codes

L9View →F2View →L2View →

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