*In October 2017, the Department of Energy implemented a new testing procedure which takes different factors into account and generates a lower BTU rating of portable air conditioners to indicate capacity. However, the actual capacity has not changed – the difference is simply due to the different testing procedure. There have been no internal changes to these units, and the functionality remains the same. Please refer to room size guidelines to find the portable air conditioner that best meets your needs. Please also refer to the AHAM website.