BoilerFaultCodesTechnical description
Central heating thermistor unplugged. Thermistor cable defective/broken, thermistor faulty. Check that thermistor attached correctly to pipe
What causes this fault?
This fault occurs when the boiler's internal computer loses communication with the sensor that monitors the temperature of the water sent to your radiators. The most common cause is the sensor itself failing due to age or internal wear, though it can also be triggered by a loose or damaged wiring connection inside the unit.
This fault is often more frequent during the autumn and winter months when the boiler is suddenly under higher demand after being inactive during the summer.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.