Your boiler is having trouble measuring the temperature of your hot water because of a faulty internal sensor or a wiring issue.
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: Domestic hot water (DHW) sensor short circuit – check connections to DHW sensor are in place
What causes this fault?
This fault occurs when the boiler's internal computer receives an incorrect electrical signal from the sensor that monitors your hot water temperature. The most common reason is that the sensor has suffered a physical failure or an electrical short, preventing the boiler from knowing how hot the water is. It can also be caused by loose or damaged wiring 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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