BoilerFaultCodesYour boiler's hot water sensor has stopped working correctly, which means the system cannot safely tell how hot your water is.
This fault should be looked at by a Gas Safe engineer within the next week or two. It may get worse if left.
Technical description: DHW THERMISTOR FAULT
What causes this fault?
This fault occurs when the sensor responsible for measuring your tap water temperature fails or sends a signal that is out of range. The most common reason is the internal component of the sensor degrading over time, though it can also be caused by loose or corroded electrical connections between the sensor and the main control board.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
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