Air-to-air heat exchangers recirculate the air inside the enclosure, cooling it using the cooler ambient air which is passed over a cross-flow heat exchanger. The two air flows are kept entirely separate, thus ensuring any dust, dirt or other contaminants are kept away from the electrical or electronic equipment.
The greater the difference between the internal and external air temperatures, the more heat may be removed from the cabinet. Rittal air-to-air heat exchangers need less maintenance than fan-and-filter units, due to indivudual controls for the internal and external fans, as well as easy-to-remove cassettes. The internal temperature within the enclosure is also constantly displayed so users can tell at a glance that the unit is operating optimally.
If temperatures within an enclosure get too high then a floating fault signal will sound to alert the user immediately about an impending problem.
