Your boiler's fan is not spinning fast enough to clear the pipes, which prevents the system from safely lighting the gas to provide heating or hot water.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Insufficient fan speed for ignition
What causes this fault?
This fault occurs when the boiler's management system detects that the fan is rotating too slowly to safely expel exhaust gases. The most common reasons are a buildup of debris or dust hindering the motor, a failing electronic component on the fan itself, or the main control board failing to send the correct voltage to the motor.
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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