BoilerFaultCodesYour boiler is struggling to understand the outdoor temperature, which might make your heating feel less efficient or slightly inconsistent.
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: Insecure wiring at boiler/sensor, or incorrect resistance values (31.0-35.0 kΩ at 0°C, 15.0-16.5 kΩ at 15°C, 7.7-8.5 kΩ at 30°C).
What causes this fault?
This fault occurs when the boiler loses a reliable electrical signal from the sensor located on your outside wall. The most common reasons are moisture getting into the sensor casing, wires becoming loose or corroded over time, or the internal component failing and sending an incorrect temperature reading.
This fault is more common during autumn and winter, as heavy rain or freezing conditions can accelerate the corrosion of exposed wiring or cause moisture ingress in the sensor.
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 Outside Sensor Fault — no call-out fees, no surprises.
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