The valve balloon system pulls air into the unit with the air pump. While using the tube inhalation technique, you attract air throughout the vape using your lungs, so no pump is required. Either way, the air flows up through the heater, and heats up in history time (see https://sativa-strain-body-high26787.glifeblog.com/10879533/volcano-hybrid-vs-classic-things-to-know-before-you-buy