BoilerFaultCodesYour boiler has stopped working because its internal sensors or control board have detected an electrical communication problem and it can no longer monitor the temperature safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Faulty thermistor or Faulty PCB
What causes this fault?
This fault occurs when the boiler's internal thermometer, known as a thermistor, fails to send a clear electrical signal back to the main control board. The most common reason is that the sensor has degraded over time or the electronic board has developed a fault, preventing the system from safely monitoring the water temperature.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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