BoilerFaultCodesTechnical description
Final fault, e.g.: primary NTC, water pressure, fan/flue problem, ignition/lockout problem
What causes this fault?
This fault occurs when the boiler's internal safety sensors detect a critical issue that prevents safe operation, such as the system losing water pressure or the burner failing to light correctly. It acts as a final safety barrier, often triggered by a failing temperature sensor or a hardware component like the fan or ignition system reaching the end of its life.
Engineer required
This is a high severity fault. Stop using the boiler and call a Gas Safe registered engineer. Do not attempt gas-related repairs yourself.
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