BoilerFaultCodesYour boiler has detected that the water levels inside the system are incorrect, or the sensor that monitors the water level is faulty.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Float switch fault detected by diagnostic feature.
What causes this fault?
This fault occurs when the internal water level sensor fails to signal that the boiler has sufficient water to operate safely. The most common reasons are a physical blockage or debris interfering with the float's movement, or an electrical failure within the sensor itself that prevents it from communicating with the main control board.
Engineer required
This fault requires a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
Find a Gas Safe engineer
Search the official register for a qualified engineer in your area.
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