BoilerFaultCodesTechnical description
Flow sensor open circuit – check connections to flow sensor are in place
What causes this fault?
This fault occurs when the boiler's main control board loses the electrical signal from the sensor that monitors the temperature of the water being sent to your radiators. The most common reason is a physical failure of the internal thermistor or a loose connection in the wiring that prevents the system from safely tracking heat levels. Because the boiler no longer knows how hot the water is, it shuts down as a safety precaution to prevent overheating.
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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