BoilerFaultCodesYour boiler has detected an issue with the electrical components responsible for venting waste gases safely from the system, preventing it from firing up.
Book a Gas Safe engineer within 24–48 hours. Your boiler may be unsafe or could break down completely if left.
Technical description: Air pressure switch fault, Fan fault, or Faulty PCB
What causes this fault?
This fault occurs when the boiler's safety system cannot confirm that the fan is successfully pushing waste gases out of the flue. The most common reason is that the fan motor has seized or the internal air pressure sensor has failed to register the necessary vacuum to allow the burner to ignite safely.
This fault often appears during the first cold spell of autumn when a fan that has sat idle all summer struggles to spin up or becomes stuck due to a buildup of debris.
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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