BoilerFaultCodesYour boiler has detected a sensor error relating to how it measures water temperature, causing it to stop running 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: Go to Thermistor section of the fault finding instructions.
What causes this fault?
This fault occurs when the boiler's internal sensors stop providing accurate readings of the water temperature, leading the system to shut down to prevent overheating. The most common reason is that the thermistors have either worn out over time or have developed a short circuit in the internal wiring. This prevents the control board from knowing if the water is at a safe temperature to continue firing.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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