BoilerFaultCodesYour boiler has stopped working because it thinks the main water temperature sensor is broken or there is a problem with its internal wiring.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Short-circuit in feed temperature sensor: Sensor plug has mass short to the casing, short-circuit in wiring loom, sensor faulty
What causes this fault?
This fault occurs when the boiler's control board detects an electrical short-circuit coming from the main temperature sensor. It usually happens because the internal components of the sensor have failed or the insulation on the connecting wires has worn away and touched the metal casing. Because the boiler can no longer safely monitor how hot the water is getting, it shuts down as a safety precaution.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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If repair costs are adding up, a new energy-efficient boiler could be the smarter long-term choice.
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