BoilerFaultCodesTechnical description
DHW thermistor fault
What causes this fault?
This fault occurs when the internal sensor responsible for monitoring your hot water temperature has failed or is sending incorrect readings to the main control board. The most common reason is that the sensor has suffered from electrical degradation or a minor internal leak has caused corrosion on the wiring connections. When this happens, the boiler stops heating water as a safety precaution because it can no longer accurately gauge how hot the water is.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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