BoilerFaultCodesYour boiler is having trouble communicating with the outdoor temperature sensor, which helps it run more efficiently based on the weather.
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 Probe fault (if fitted)
What causes this fault?
This fault occurs when the boiler loses the electrical signal from the sensor located on the outside of your house. The most common reasons are a broken connection in the outdoor wiring, corrosion on the sensor's internal terminals, or a failure of the sensor itself due to weather exposure.
This fault is more likely to be noticed during the autumn and winter months when the boiler relies on the outdoor sensor to calculate how much heat is needed to keep your home warm.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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A boiler cover plan would cover faults like F6 — no call-out fees, no surprises.
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