BoilerFaultCodesYour boiler is struggling to work out how hard it needs to fire because the sensor that monitors the weather outside has stopped sending a signal.
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: Outside temperature sensor defective – check the connecting lead
What causes this fault?
This fault occurs when the boiler loses communication with the sensor mounted on your external wall, which tells the system how cold it is outside. The most common reasons are the sensor's internal components failing due to water ingress or the thin communication wire being damaged or corroded over time.
This fault is often noticed during the first cold snap of autumn, as the boiler attempts to use the sensor to adjust its heating curve for the changing weather.
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 1068 W — no call-out fees, no surprises.
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