Low
LED 1 on Myson System 50

Your boiler is currently checking that there is enough airflow for it to start up safely; this light should turn off automatically once the system is ready to fire.

Reviewed by the BoilerFaultCodes Editorial Team · Last reviewed

Monitor it

This is a minor fault. Keep an eye on it and mention it at your next annual boiler service. Reset the boiler and see if it clears.

What the manual says

Manufacturer manual

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

Shared across the 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 fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.

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LED 2View →LED 3View →

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