BoilerFaultCodesTechnical description
Main burner fails to light, pilot burning - Blocked main burner injector.
What causes this fault?
This fault occurs when debris or soot builds up inside the tiny hole of the main burner injector, physically blocking the gas from reaching the burner. While the pilot light stays lit to prove there is a flame, the blockage prevents the main fire from starting, meaning the boiler cannot produce heat for your radiators or water. The most common reason is a buildup of carbon or microscopic dust particles over several years of operation.
This issue often comes to light during the first cold spell of autumn, as the burner is required to run for longer periods and at higher capacities after being mostly dormant over the summer.
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.