BoilerFaultCodesYour boiler's central heating temperature sensor has likely failed, preventing the system from accurately measuring how hot the water is.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: CH thermistor fault. Check resistance is between 12kW and 1.5kW.
What causes this fault?
This fault occurs when the boiler's internal computer can no longer read the temperature of the water in your radiators. Usually, the sensor has physically degraded or developed an electrical short, which causes the boiler to shut down as a safety precaution to prevent overheating. In some cases, it can be caused by loose or damaged wiring connecting the sensor to the main control board.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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