BoilerFaultCodesTechnical description
Central heating return negative temperature coefficient (NTC) fault
What causes this fault?
This fault occurs when the internal sensor responsible for measuring the temperature of the water returning from your radiators fails or sends an incorrect signal to the main control board. The most common reason is that the sensor has suffered a technical failure or the wiring connecting it to the boiler's computer has become loose or damaged. Because the boiler can no longer monitor the safety of the return water, it shuts down to prevent any internal damage.
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.
Find a Gas Safe engineer
Search the official register →