High
LED Flashing on Johnson Starley J32 System ET

Your boiler's internal fan is failing to start or power up, which means the unit cannot safely clear exhaust gases and will refuse to ignite.

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

The fan is not connected, or the capacitor is not connected, or there is a short circuit in the fan supply.

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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