BoilerFaultCodesYour boiler has lost communication with the sensor that monitors water temperature, causing the system to shut down for safety.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Open circuit on flow sensor
What causes this fault?
This fault occurs when the boiler's internal computer can no longer detect a signal from the sensor that monitors the temperature of the water leaving the heat exchanger. It is usually caused by the sensor failing internally or a loose connection in the wiring that links the sensor to the main control board.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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