BoilerFaultCodesTechnical description
Check main burner injector, supply on terminals of main gas valve, or PCB connections
What causes this fault?
This fault occurs when the boiler's control system attempts to start the heating cycle but fails to establish a sustained flame at the main burner. The most common reasons include a blockage in the pilot assembly preventing the gas from reaching the burner or an electrical failure where the gas valve is not being told to open by the control board.
This issue is more frequent during the first cold spell of autumn when dust or debris accumulated over the summer can clog the burner injectors or pilot light.
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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