BoilerFaultCodesYour boiler has stopped working because one of its internal temperature sensors has developed an electrical fault and can no longer send information to the main control board.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Return sensor short circuit. Check cable/connections not damaged. Renew sensor/cable. Check connections on control
What causes this fault?
This fault occurs when the electrical resistance in the return temperature sensor drops to a level that indicates a short circuit, meaning the boiler can no longer monitor the water temperature accurately. The most common reason is internal failure of the sensor's thermistor component, but it can also be caused by water damage or heat degradation affecting the wiring harness.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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