Low
8 nn on Keston C90 / C110

Your boiler has successfully finished heating the specific zone or area requested and is currently in a standard standby mode.

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 at end of heat request from zone 2

Engineer required

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

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