BoilerFaultCodesYour boiler's safety sensor has detected a problem with its electrical circuit, meaning it cannot confirm if there is enough water in the system to operate safely.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Dry fire sensor: Sensor failed open or closed circuit
What causes this fault?
This fault occurs when the boiler's dry fire sensor, which prevents the unit from overheating without water, fails to send a clear electrical signal to the control board. The most common reason is an internal electrical failure within the sensor itself or loose connection pins in the wiring harness. In some cases, a fault on the main control board prevents it from reading the sensor correctly, leading the boiler to shut down for safety.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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