Low
F6 on Keston Heat 80

Your boiler is having trouble communicating with the external temperature sensor that monitors the weather outside, which may cause your heating to be less efficient.

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

F2View →F9View →

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