Refilling a vaporizer differs per type. This is the biggest difference between a convection vaporizer and a conduction vaporizer.
With a convection vaporizer, also known as a hot air vaporizer, you fill a capsule or separate chamber with crumbled herbs. You can then start using the cannabis vaporizer.
With a conduction vaporizer, also known as a hot plate vaporizer, you place crumbled herbs on a plate in the weed vaporizer. The weed vaporizer can then be put into use.
With both models, when the herbs are brown to black, the herbs have been used up and new herbs are needed to continue evaporating.