BoilerFaultCodesYour boiler 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 (T1).
What causes this fault?
This fault occurs when the boiler's control board receives a signal from a temperature sensor that it doesn't recognise or expect. It typically happens because an incompatible part was installed during a repair, or because the internal settings have accidentally been configured for a solar heating system that isn't actually there.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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