BoilerFaultCodesTechnical description
Fan and pump running
What causes this fault?
This status occurs when the boiler's internal computer is waiting for the flame sensors to confirm the burner has successfully lit. It usually signals a breakdown in communication between the ignition components and the control board, often caused by worn-out spark electrodes or a faulty gas valve failing to release fuel. If the boiler cannot confirm a safe flame after several attempts, it will eventually stop trying and display a full fault code.
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.
Find a Gas Safe engineer
Search the official register →