BoilerFaultCodesYour boiler has stopped working because it cannot accurately measure the temperature of the water entering the system.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Open circuit on inlet sensor
What causes this fault?
This fault occurs when the internal control board loses connection with the sensor that monitors the temperature of the water entering the boiler. The most common cause is a failure within the sensor's internal electrical components or a loose connection in the wiring that prevents the boiler from receiving a signal. Because the boiler no longer knows the temperature of the incoming water, it shuts down as a safety precaution to prevent overheating.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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