Low
F6 on Keston Celsius 30

Your boiler is having trouble communicating with the outdoor thermometer that helps it adjust to the weather, which may affect its efficiency.

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

Outside sensor failure

Engineer required

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

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Related fault codes

F1View →F7View →F9View →

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