BoilerFaultCodesYour boiler is struggling to accurately measure the temperature of your hot water, which usually means your taps will only run cold.
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 NTC sensor defective.
What causes this fault?
This fault occurs when the temperature sensor responsible for your hot water fails to send a reliable signal to the boiler's internal computer. It is usually caused by the sensor's internal electrical resistance failing over time or mineral deposits building up on the part, preventing it from reading the water temperature correctly. As a safety precaution, the boiler stops heating the water because it can no longer monitor how hot it is getting.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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