BoilerFaultCodesYour boiler has lost its connection to the outside temperature sensor, which usually helps the system adjust its heat based on the weather.
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: Short circuit of outdoor sensor
What causes this fault?
This fault occurs when the electrical signal from the outdoor sensor is interrupted, usually due to moisture getting into the sensor housing or damage to the external wiring. It can also be caused by a loose connection or a pinched wire somewhere between the boiler's control board and the outside wall.
This issue is more frequent during periods of heavy rain or high humidity, as moisture can penetrate the sensor's casing and cause the electrical circuit to 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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