BoilerFaultCodesTechnical 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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