BoilerFaultCodesTechnical description
Domestic hot water (DHW) negative temperature coefficient (NTC) thermostat sensor fault (s.c.) or DHW NTC sensor fault (o.c.).
What causes this fault?
This fault occurs when the sensor responsible for measuring the temperature of your hot water fails or sends an unreadable signal to the main control board. The most common reason is that the internal components of the sensor have worn out over time, or the electrical connection between the sensor and the boiler has become damaged or loose.
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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