BoilerFaultCodesYour boiler has lost communication with the sensor that monitors the weather outside, meaning it may not heat your home as efficiently as usual.
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 sensor error
What causes this fault?
This fault occurs when the boiler can no longer detect a signal from the small sensor located on the outside of your home. The most common reason is that the external wiring has become damaged by the elements or the internal circuitry of the sensor itself has failed due to moisture ingress.
This fault is more common during autumn and winter, as heavy rain or freezing temperatures can compromise the sensor's casing or cause the electrical connections to corrode.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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A boiler cover plan would cover faults like E10 — no call-out fees, no surprises.
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