BoilerFaultCodesYour boiler is having trouble reading the outside temperature because the sensor or its wiring has developed an electrical fault.
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: Short circuit of outdoor sensor S6.
What causes this fault?
This fault occurs when the boiler's control system detects an abnormal electrical signal, suggesting that the wires for the outdoor temperature sensor have touched each other or the sensor itself has failed internally. The most common reason is water ingress into the sensor casing or physical damage to the cable running along the outside of your property. Without an accurate reading, the boiler cannot adjust its efficiency based on the weather conditions outside.
This fault is more common during autumn and winter when heavy rain or frost can penetrate the sensor housing and cause an electrical short.
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 F027 — no call-out fees, no surprises.
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