Window and Wall Unit 15000 BTU Air Conditioner Only 115v Friedrich Chill Premier Inverter 15,000 BTU 115v Cooling Only Window & Wall Unit The Chill Premier Inverter has State-of-the-art Precision Inverter Technology which provides efficient, precise temperature control and Library-Quiet sound levels. The units come with a simplified installation process and include an adaptable design that allows windows to be opened after the unit has been installed. The Chill Premier Inverter units are Energy Star certified and are up to 35% more efficient than other window air conditioners on the market.