High
FAN LOCKOUT on Main 12 Heat ErP range

Your boiler has temporarily stopped working because it has detected an issue with the internal fan that safely removes exhaust gases.

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

Unplug 3-way PCB connector & unplug fan. Unplug the smaller of the 6-way PCB connector.

Shared across the 12 Heat ErP 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.

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

F4View →F8View →E119View →

All 4 fault codes on the 12 Heat ErP range

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

IGNITION LOCKOUTOVERHEAT LOCKOUTTHERMISTOR

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