Low
SG1 on Ideal Classic Se

This code simply confirms that your boiler is currently in the process of lighting the flame, and it should disappear as soon as the burner is successfully ignited.

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

Flashes to indicate ignition operation (stops after detection)

From this model's manual
Verified against the Ideal Boiler Classic Se9ff Se12ff Se15ff Se18ff Se21ff Se24ff Se30ff installation & service manual, page 29.
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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