BoilerFaultCodesWhat the manual says
Manufacturer manualControl mode: Cylinder temperature sensor lead break
What causes this fault?
This fault occurs when the boiler loses its electrical connection to the temperature sensor attached to your hot water tank. The most common reason is that the thin wiring has become loose, corroded, or accidentally damaged, preventing the boiler from knowing if your water is hot enough. Because the control board can no longer monitor the safety of the cylinder, it stops providing hot water to prevent overheating.
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.
Avoid the next call-out bill
A cover plan would handle faults like 9C: no call-out fees, no surprise bills.
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