BoilerFaultCodesYour boiler has lost communication with the external temperature sensor, which helps it adjust your heating based on the weather outside.
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: Clas HE evoClas he evo systemE-combi evoE-system evo
What causes this fault?
This fault occurs when the main control board can no longer detect a signal from the sensor located on the outside of your property. The most common reason is that the thin electrical wiring connecting the boiler to the outdoor sensor has become damaged, corroded, or loose. In some cases, the sensor itself may have failed due to water ingress or age, preventing the boiler from knowing the outdoor temperature.
This fault is often discovered during the first cold snap of autumn when the heating is turned back on and the boiler attempts to use weather compensation data.
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 202 — no call-out fees, no surprises.
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