Low
F6 on Keston Heat 45

Your boiler has lost communication with the sensor that measures the temperature outdoors, which may cause it to run less efficiently or fail to heat up properly.

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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