BoilerFaultCodesYour boiler has detected that the sensors measuring water temperature going in and out are giving conflicting readings, so it has shut down as a safety precaution.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Flow/return temperature sensor permanent deviation
What causes this fault?
This fault occurs when the boiler's internal computer notices that the two sensors monitoring water temperature are reporting figures that don't match up logically. The most common reason is that one of these sensors has become faulty or uncalibrated, but it can also be triggered if the wiring connecting them to the main control board has been damaged or loosened.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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