BoilerFaultCodesTechnical description
Central heating thermistor sensor error
What causes this fault?
This fault occurs when the boiler's internal computer loses communication with the temperature sensor that monitors your central heating water. The most common reason is that the sensor has electronically failed or 'drifted' over time, but it can also be caused by loose or damaged wiring connecting the sensor to the main control board.
This fault is more common in autumn when systems are turned back on after summer, as the sudden change in temperature and increased demand can cause an aging sensor to finally fail.
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.
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