Refolution in the cryotherapy


For our customer COOLINN we developed in 2019 a revolutionary cold sauna with air-cycle refrigeration technology from Mirai Intex. It is able to reach stabe temperatures of down to -130 ° C room temperature and is characterized by many special features:


  • Environmentally friendly and safe with the refrigerant air with GWP 0 and maximum pressures of 0.9 barg - so there are no environmental regulations

  • No risk of suffocation and no risk of explosion

  • Real temperatures with optimal temperature distribution for the best user experience and impact

  • Low-maintenance and long-lasting technology - oil-free turbo machine

  • Industrial design with durable and stable components

  • Energy efficient

  • Easy to clean


In fall 2020, we installed a heat recovery system for COOLINN. The air cycle refrigeration machine heats air from the outside to up to 70°C to cool itself down. This warm exhaust air is blown into the lounge next to the cold sauna. In addition, clients have the possibility to get blown at before using the cold sauna for drying them off.

Air duct with three-way flap in the engine room

Outlet into the lounge with thermostat and boost switch

The COOLINN in Karlsruhe-Durlach is the first full-body cold sauna operated with an air-cycle refrigerationn machine which also uses its exhaust air to heat the ambience and has an additional, innovative drying function for its customers.

Project Partner



At COOLINN in Karlsruhe, the technology can be experienced live and our whole-body cryo therapy chamber can be purchased.



Mirai Intex's air cycle refrigeration systems can be purchased from Secon GmbH in Germany.


Mirai Intex

Mirai Intex is the manufacturer of air cycle refrigeration systems with the air-mounted turbo compressor expander.



Technical article

The refrigeration + air conditioning

Technical article

Health industry BW specialist article

Fire one

Technical article


Heat recovery