BoilerFaultCodesYour boiler is struggling to accurately measure the temperature of your hot water, which usually prevents it from heating the water correctly.
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: Hot water NTC sensor defective.
What causes this fault?
This fault occurs when the sensor responsible for monitoring your hot water temperature fails to send a clear signal back to the main control board. The most common reason is that the sensor has developed a physical breakdown or electrical short after years of constant temperature changes, though loose or corroded wiring can also mimic this failure. Because the boiler no longer knows how hot the water is, it stops heating it as a safety precaution to prevent scalding.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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