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.

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.

What the manual says

Manufacturer manual

Outdoor Temperature Sensor Fault

Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
Plain-English guidance below. Severity, DIY steps, costs and parts are our interpretation to help you act, not text from the manual.

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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Avoid the next call-out bill

A cover plan would handle faults like F6: no call-out fees, no surprise bills.

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Related fault codes

All 118 fault codes on the Vizo 24

Seeing a different code? Every code this model can display, in one place.

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