Wax Melt Vapour
A slight vapor mist is typical, but if you notice an excessive amount rising from the burner, it indicates the wax is too hot, causing rapid burning of the fragrance oil. In such cases, extinguish the tealight, try a smaller one, and observe if the vapor reduces. If successful, stick with smaller tealights. If not, the burner might not be suitable for wax melts, possibly designed for oils.