BoilerFaultCodesYour boiler has detected an electrical fault with a sensor that monitors the water temperature flowing into your heating system, leading it to shut 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: Short circuit: System flow temperature sensor (low loss header)
What causes this fault?
This fault occurs when the electrical signal from the temperature sensor is interrupted or fails to send back the correct information. The most common reason is a physical failure of the internal sensor components or damage to the wiring that connects the sensor to the boiler's main control board. If the boiler cannot accurately measure how hot the water is, it shuts down to prevent the system from overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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