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 is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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