BoilerFaultCodesYour boiler has detected a problem with the sensor that monitors the temperature of the water leaving the unit, usually resulting in the system shutting 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 thermistor error
What causes this fault?
This fault occurs when the control board loses communication with the sensor that monitors the temperature of the water as it leaves the boiler. The most common reason is that the sensor has physically failed or 'drifted' out of its correct electrical range, but it can also be caused by loose or damaged wiring. Because the boiler no longer knows how hot the water is, it shuts down as a safety precaution to prevent overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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