High
neons flashing (Section D) on Potterton Performa System HE

Your boiler has detected that the internal fan responsible for safely exhausting fumes is not rotating or working correctly, so it has shut down to keep your home safe.

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 speed check - Fan jammed or faulty winding or primary temperature sensor faulty (resistance approx 11K ohms).

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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