BoilerFaultCodesWhat the manual says
Manufacturer manualThermistor error
Shared across the range
This code is shared by the boilers in this range, which use the same control board. It may not be printed in this exact variant’s manual.
What causes this fault?
This fault occurs when the boiler's internal temperature sensor, known as a thermistor, fails to send a reliable signal to the main control board. The most common reason is that the sensor has developed an electrical fault or has simply worn out over time, meaning it can no longer accurately monitor the water temperature. As a result, the boiler shuts down to prevent itself from 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.
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