Low
F6 on Heatline Vizo 24

Your boiler is having trouble readng the temperature outside, which it usually uses to adjust how hard it needs to work to heat your home.

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

Outdoor Temperature Sensor Fault

DIY fix possible

Turn the boiler power switch to offWait 30 secondsTurn the power back on and press the reset button

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Related fault codes

F1View →F2View →

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