People have asked me many times what is the difference between an oil diffuser and an oil burner and which one is better. I use both interchangeable and I enjoy both but have preferences for when I use them. Oil Burner The oil burner consists of a bowl on top that is filled with water and essential oils. The tea light candle is placed underneath it and heats up the water. The steam carries the essential oils into the air. The therapeutic properties of the essential oil are somewhat degraded through the heating process. It changes the molecular structure and this is what reduces the therapeutic benefits. This method is.