High Lockout
E03 on Potterton Gold HE

Your boiler's fan has stopped working, which means it cannot safely blow exhaust gases out of the flue and has shut down as a safety precaution.

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.

Technical description

Fan jammed or faulty winding, fan connections, or PCB failure.

What causes this fault?

This fault occurs when the boiler's control system can no longer detect the fan spinning at the correct speed to safely remove exhaust fumes. The most common reasons are either the fan motor itself burning out over time or a build-up of dirt and debris physically jamming the internal blades.

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

E160View →

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