BoilerFaultCodesYour boiler has shut down because the internal exhaust gases have reached a dangerously high temperature, triggered by a safety sensor.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Exhaust gas temperature sensor error – excessive temperature alarm.
What causes this fault?
This fault occurs when the gases leaving your boiler's exhaust system become too hot, which can damage internal components. The most common reasons are a significant buildup of debris or limescale inside the heat exchanger or a blockage in the flue pipe that prevents heat from escaping properly. In some cases, the sensor itself may have failed and is sending an incorrect temperature reading to the boiler's computer.
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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