High
LED 2 on Myson System 50

Your boiler is struggling to clear air through its internal system effectively enough to safely ignite the burner.

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

Will remain on until the fan has produced enough air for complete combustion at high rate - high rate air detector.

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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