BoilerFaultCodesYour boiler has stopped working because one of its internal temperature sensors has broken or become disconnected.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: NTC1 open
What causes this fault?
This fault occurs when the boiler's control system can no longer read the temperature from the flow sensor, which acts like a thermometer for the water leaving the unit. The most common reason is that the sensor's internal electrical circuit has failed or a connecting wire has come loose, meaning the boiler shuts down for safety because it cannot monitor if it is overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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