Atmospheric steam generators
The atmospheric steam generators are in a class by themselves. They don’t use pressure to create steam. They get hot but don’t create super high temperature that create steam traps. The temperatures are more uniform. Since they are a slow burn, you won’t have scorching ceilings and these types use minimal water and produce the least condensate. For those that are considering full body steam therapy, it is very easy to control the steam when fewer grams of steam are being released at once instead of the generator dumping the entire load at once.
Atmospheric generators are dual tank models that have an inlet tank and a boiler tank. The boiler tank is much smaller than the pressurized tanks. The atmospheric tanks have a low watt density and more heating element area is touching minimal water to create a very dry steam and low condensate. Also, atmospheric generators are super quiet since they don’t work even at 10 psi that the lowest pressurized generators work at.
These non pressurized generators are very expensive to make. They cost around 500 to 600 dollars per killowatt on average. So, if you needed at 6KW generator, it would retail around 3000 to 3600 dollars. As a reference, a 20 psi generator usually costs around 175 to 200 per killowatt. The really cheap 10psi models cost about 100 dollars a killowatt. These are the types you find on eBay and amazon mostly imported 100% from China. They put out so much condensate you will probably have drippings from the ceiling the entire time once the ceiling temperature meets the room temperature. Water hammer is another problem.
I urge people who want this type of dry steam to inquire about returned models. It is almost an every day thing that someone returns a wrong size and needs to trade back their generator for the correct killowatt size. I personally only take returns if no water has been used in the generator by the end user or I have them sent back to the manufacture to certify them.
Update: so many are still confused on what atmospheric steam generators are compared to the pressurized generators and why someone would want to use atmospheric over pressurized.
So, atmospheric is not better it is for people that want that type of steam. For those that want to stay at a constant temperature and especially those who want to stay within 110 to 114 degrees which is the comfort zone that most people try to stay in. When the steam comes out slowly, a slow burn, it's much more controllable than having it come out in a quick burst. A fast burn pressurized steam might take 18 seconds to release the load of steam to have the room reach the temperature you set it at. A continuous atmospheric slow burn might take 1 minute and 18 seconds to release the same grams of steam. If using a marine grade fan to bring the steam that has risen to the ceiling down to the lower body, it is much easier to control the room temperature when it comes out at a slow burn.
The problem with most fast burn generators is that when it releases the load and you are using a fan to keep the whole room at near the same temperature (mixing ceiling trap air with cooler floor air), the room becomes nearly the same temperature and the body can go into full body vasodilation. Full body steam therapy is what many people have not experienced. Only half body steam therapy.
So, when if you get a pressurized generator, when there is a long duty cycle with no steam, even if you are in the 110 114 degree comfort zone, you might only be in it for a minute or so then you are out of it and the body can be in a 90 98 degree zone, for example, and many people don't want to take a 45 minute to an hour steam bath to heat their core up and feel they want to get out (see cardiac drift page). If you can stay in the 110 114 degree range and at 100% humidity for the entire session, that is something only very few people ever experience. I get in and get out in about 20 minutes (especially if I use my heat co-efficient fan) or about 25 minutes if I don't use it.
This is the fan I use. If the steam is dry and low condensate, it feels amazing to put this behind my back or have it blowing on my legs. It is battery powered so I can move it around where I want it. When it blows on your body it makes the steam feel way more intense.
Notice: if you have a pressurized steam generator and when there is a duty cycle of no steam, the lower room becomes cooler and it is not pleasant to blow cool air at the seat level on your body. Using this with the Kona wall fan is what makes this really effective. The steam must be constant and continuous and have low condensate to make this really comfortable.