Advanced Inverter Technology developed by Amcor constantly adjusts output to maximize comfort and minimize energy costs. A NEW, High SEER, practical alternative to the expense of central air conditioning, as well as an aesthetically pleasing alternative to window or through-the-wall air conditioners. Please note: AmcorAire Ductless Mini-Split units are Heat Pumps and will operate in ambient conditions down to about 17?F (other conditions i.e. humidity and wind may increase or decrease working temperature and efficiency). For climates that routinely drop below 17?F, Amcor recommends a backup source of heat. Units that utilize Amcor's Advanced Inverter Technology can operate at temperatures down to -4?F, but still may require a backup source of heat depending upon the application. Consult... Less