BoilerFaultCodesYour boiler is having trouble communicating with the weather sensor or temperature probe located outside your home.
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 sensor fault (if fitted)
What causes this fault?
This fault occurs when the boiler's control board loses its connection to the sensor located on the outside of your property. The most common reason is that moisture or corrosion has damaged the sensor's internal circuitry, or the thin wires connecting it to your boiler have become broken or loose.
This fault is more common during autumn and winter, as heavy rain or freezing temperatures can cause water ingress or physical damage to the external sensor unit.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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