A traditional dry sauna, also known as a Finnish sauna, generates heat by heating up rocks and the air is typically kept dry with low humidity. The heat is then transferred to occupants' bodies through convection and radiation.
On the other hand, a wet sauna, or steam sauna, introduces moisture into the air by pouring water onto the hot rocks or using a steam generator. This sauna bath machine increases the humidity levels, creating a more moist environment.
Many modern wet and dry sauna heaters are designed to provide both wet and dry experiences. They include a water source for generating steam and can be adjusted to control the level of humidity in the sauna. This allows users to choose between a dry heat or a more humid heat depending on their preference.
The dry & steam sauna combined the two types of sauna in one unit which allows you to experience two type of sauna in one sauna room. For the traditional sauna heater, you can only increase the wet by pouring water to the sauna stones which is harmful to the heating elements and shorten the lifespan of the heating elements. While some may enjoy the lower heater and more humidity while this unit can meet their desire.
The sauna room would become very dry by the high temperature of the electric steam sauna heater. Theoratically, it is not allowed to pour water on the sauna stones to increase the humitity. But it seemed it has become a normal phenomenon people using water to increase the humidity using the dry sauna heater. While with the sauna heater's development, the dry sauna heater and steam generator has combine to one unit to make it possible to make the sauna both wet and dry.
It's depends on what you need. Some may enjoy the dry heater while others enjoy the lower heat with high humidity. Both of them have the same function as a sauna.
Both dry & steam sauna heaters need to be vented to make the sauna room work properly.