What is the difference between dewar or pressurized tank?


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With Cryomed Pro you have two options for nitrogen feed, from non-pressurized Dewar tanks or from bigger pressurized containers. They are not interchangeable, you cannot have one replaced with the other, and therefore, it is important from the very beginning to choose the one which will be more suitable for your needs.

Here are several factors to be considered

Non-pressurized Dewar tanks are smaller and easier to handle. They are rolled into a cryosauna for the time of the session. There is a pipe in the cryosauna which goes down into the Dewar to pump nitrogen steam into the cabin during a session.

A Dewar weighs 14.5 kgs when empty and comes with a wheeled platform which makes it easy to move. Apparently, it requires less space than a bigger tank and would be easier to refill. 

Cryotherapy cabin with dewar and operator

Cryotherapy cabin with dewar and operator

A pressurized tank stays outside the cryosauna. They are connected with a hose which is provided by your nitrogen supplier. Optionally, you can buy a 2-meter hose from us. Nitrogen flow is regulated by a cryogenic valve which opens at regular intervals when a session starts, with pressure pushing nitrogen through the hose into the cryosauna. The pressure in the tank should be between 1.5 and 2.5 bar. 

Pressurized tanks are heavier and bigger. They are not included in your cryosauna’s price, but can be rented or bought from your nitrogen supplier.  It is better to consult your supplier about any restrictions linked to your location. E.g., if your business is located on the 10th floor in a high-rise building without a service elevator, your options might be limited. 

As nitrogen consumption affects the price of sessions, there are a couple of things to bear in mind. For a cryosauna you will need technical liquid nitrogen, not a medical grade, so usually there is no problem to find a supplier.

Cryosauna Cryomed Pro (pressurized type)

Cryosauna with dewar vessel

Consumption obviously depends on the session time which varies from 1.5 to 3 minutes, the temperature in the cabin (for a beginner the operator can choose -130C, for a veteran user -150C is a more likely option). You can save nitrogen by scheduling sessions one by one with no more than 10 minute gaps in between. In addition, nitrogen consumption and evaporation from tanks depends on the environment, too – humidity, room temperature. That is why the number of sessions you can get from one tank is tentative. 

Non-pressurized Dewar tanks have 40-liter capacity (or 32 kgs, as 1 l of liquid nitrogen weighs 0.8 kgs), which is sufficient to have one cooling and approximately 8 to 10 sessions. You get two tanks together with your cryosauna, and you can order additional ones. This type is good if you plan to have some 10 customers per day or you buy a cryosauna for home use.

Pressurized tanks’ capacity varies from 100 l to 5,000 l. As an example, you can have some 60 sessions out of a 240-liter (192 kgs) tank. This is an economic version which doesn’t require too frequent refills. It is recommended for businesses with higher number of daily sessions, like a gym, a spa, or a clinic.

Pressurized tanks have slightly higher evaporation rate than non-pressurized Dewars, plus some nitrogen gets lost along the hose and on the junctions between the valve and the hose  and between the tank and the hose. But with a large flow of customers this loss is negligible. 

Both feed options have their pros and cons, so if you are not sure please contact us, and we will help you to choose. 

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