The LG Energy Star LW1812ER 18,000 BTU Window-Mounted Air Conditioner with Remote Control is perfect for large size rooms up to 1000 square feet. You will cool a lot and save even more with this unit's energy saver function, 24-hour on/off timer and a 10. 7 Energy Efficiency Ratio. With its stylish, full-function remote, you can even get your cool on from across the room. Plus, LG's patented Gold Fin anti-corrosion coating provides a protective shield so the unit lasts longer.