BoilerFaultCodesYour boiler has detected an issue with the sensor that monitors the temperature for your central heating, meaning it cannot safely regulate how hot your radiators get.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Faulty CH temperature probe NTC
What causes this fault?
This fault occurs when the internal sensor responsible for tracking the water temperature in your radiators fails or provides an unrealistic reading to the control board. The most common reason is that the thermistor has degraded over time or developed an electrical short, preventing the boiler from knowing when to safely turn the burner off.
This fault often surfaces at the start of autumn when the central heating is turned on for the first time after being dormant all summer.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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