BoilerFaultCodesTechnical description
CH flow thermistor error
What causes this fault?
This fault occurs when the boiler's control board loses communication with the sensor that monitors the temperature of the water heading to your radiators. The most common reason is that the internal components of the sensor have failed due to age, or the electrical connection has become loose or corroded. Because the boiler no longer knows how hot the water is, it shuts down as a safety precaution to prevent overheating.
This fault is more common in autumn and winter when the heating is first switched back on and the sensor is subjected to rapid changes in temperature.
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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