Low
F6 on Heatline Capriz 24

Your boiler is struggling to read the outdoor temperature, but it should still be able to operate using its internal settings.

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

External sensor fault (where fitted)

Engineer required

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

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Related fault codes

F7View →

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