possible that the logs/coals have left dust on the burner tray. try removing them carefully onto some newspaper(remember the order they go back as some need to be in a certain order)Hoover out the tray underneath if it is a metal tray. replace logs and try again.
If that don't work it may be your burner pressure needs altering or your injector is blocked
don't take risks though get it serviced as your fire is potentially a killer
roger
February 2007
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