BoilerFaultCodesYour boiler is unable to measure the temperature of the water flowing to your taps, which usually means the hot water production has stopped working.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Hot water thermistor open circuit.
What causes this fault?
This fault occurs when the sensor responsible for monitoring the temperature of your hot water fails or loses its connection to the main control board. The most common reason is that the internal component has reached the end of its lifespan and its electrical circuit has snapped, meaning the boiler can no longer tell how hot the water is. Occasionally, this can be caused by moisture or corrosion on the wiring pins causing a total loss of signal.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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