Your boiler has detected an electrical fault with the internal 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: Flow sensor short circuit error
What causes this fault?
This fault occurs when the boiler's internal computer receives an incorrect electrical signal from the sensor that monitors the temperature of the water leaving the unit. The most common reason is that the sensor has suffered an internal electrical failure or the wiring connecting it to the main control board has become damaged or loose. Because the boiler can no longer safely verify how hot the water is, it shuts down to prevent overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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