BoilerFaultCodesYour boiler's control system has detected that the wrong type of temperature sensor has been installed or configured for your hot water system.
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: Cylinder temperature sensor type used as collector temperature sensor (TA).
What causes this fault?
This fault occurs when the boiler's internal computer detects a mismatch between the temperature sensor installed and the settings it is expecting to see. It most commonly happens if the wrong part was used during a recent repair or if the control board has developed a software glitch that misidentifies the hot water components.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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