Low
1 nn on Keston C90 / C110

Your boiler is currently just starting the process to fire up and ignite the burner.

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.

Technical description

Module commencing ignition sequence

Engineer required

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

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