BoilerFaultCodesYour boiler has lost connection with the sensor that monitors the outdoor temperature, which might make your heating less efficient.
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
What causes this fault?
This fault occurs when the boiler can no longer communicate with the small sensor located on the outside of your property. The most common reasons are a break in the electrical wiring leading outdoors, water ingress into the sensor casing, or a complete failure of the sensor’s internal components.
This fault is more frequent during autumn and winter as a failing sensor reacts poorly to extreme temperature drops or heavy rain and frost.
DIY fix possible
Locate the reset button on the boiler control panelPress and hold the reset button for two secondsCheck if the weather compensation sensor outside looks damaged or blocked by debris
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
Gas Safe Register →Protect yourself from future repair bills
A boiler cover plan would cover faults like F6 — no call-out fees, no surprises.
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