BoilerFaultCodesYour boiler's outside temperature sensor has developed a fault or lost its connection, 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: External probe fault.
What causes this fault?
This fault occurs when the boiler loses communication with the sensor located on the outside of your home. The most common reason is that the sensor's internal circuitry has failed due to moisture ingress or the exposed wiring has been damaged by wind, rain, or garden activity.
This fault is more common during the autumn and winter months when high winds and heavy rain are most likely to damage external components or cause corrosion in the wiring connections.
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 E10 — no call-out fees, no surprises.
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