BoilerFaultCodesYour boiler has stopped heating because a internal sensor that monitors water temperature has developed an electrical fault and is preventing the burner from firing.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Burner blocked. Short circuit - boiler water temperature sensor.
What causes this fault?
This fault occurs when the boiler's internal thermometer, which monitors how hot the water is getting, fails to send a correct electrical signal to the main control board. The most common reason is that the sensor has suffered an internal electrical short circuit or the connecting wires have become damaged or loose. Because the boiler no longer knows the exact temperature of the water inside, it shuts down the burner as a primary 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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