Low
F6 on Ideal Compact

Your boiler's external temperature sensor has stopped communicating correctly, which means the system may struggle to adjust your heating efficiency based on the weather outside.

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 fault

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 →F2View →F5View →

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