Hot exhaust air or gas from industrial processes are a source of energy and in many cases they are just blown out into the environment without using its thermal energy. Higher energy cost and increasing Co2 emissions are major concerns today and to overcome that, companies are required to make their processes more efficient. First step is always to realize an internal waste heat recovery system – in this case meaning preheating fresh air by the exhaust air. Air to Air Heat Exchangers is the answer and they are most suitable for moving heat from inside an enclosure to ambient air or from one enclosed air system to another. Two phase systems like heat pipes or thermosiphons are used to transport heat from one side of the heat exchanger to the other. Warm air from the process flows around thinwalled plain tubes, cools down and condenses if necessary. Cold fresh air flows inside the tubes, is preheated by the exhaust air und then brought into the process – realizing an efficient heat recovery. Conductive Air to Air Heat Exchanger, Heat Pipe Air to Air Heat Exchanger, Thermosiphon Heat Exchangers are solutions that we offer.