The Dynasys Auxillary Power unit is designed for sleeper cabin bunk airconditioning. The Dynasys APU is powered by a 2 cylinder, water cooled Caterpillar engine and provides 24,000 BTU’s of cooling (6 kw) more than an Icepack unit. The unit also provides heating, and comes with 1000hr service intervals same as the Icepack-ES.