BoilerFaultCodesYour boiler has lost communication with the sensor that measures the temperature outdoors, which may cause your heating to run less efficiently.
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 Fault
What causes this fault?
This fault occurs when the boiler's main control board loses the electronic signal from the sensor located on the outside of your home. The most common reasons are physical damage to the external sensor unit or the wiring connecting it to the boiler becoming loose, corroded, or damaged by the elements.
This fault is more common following periods of heavy rain or extreme frost, which can cause moisture to enter the sensor housing or cause the external wiring to perish.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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A boiler cover plan would cover faults like 4.10 — no call-out fees, no surprises.
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