BoilerFaultCodesTechnical description
Cylinder temperature sensor/comfort sensor/loading sensor lead break
What causes this fault?
This fault occurs when the boiler's control system loses communication with the sensor responsible for measuring your hot water temperature. The most common reason is that the sensor has suffered an internal electrical failure or the connection wires have become damaged or loose. Because the boiler no longer knows how hot the water is, it shuts down the burner as a safety precaution to prevent scalding.
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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