Solar window heaters by Solar Window Chimney, LLC are the most attractive, economical solar air heaters on the market today. The unit sits in a standard 36W x 54 double hung window and turns it into a Smart Window. Our products use the power of the sun to heat your home, office, garage or any other space. Not only does the unit provide free clean heat from south facing windows during the winter months, it is also a multi-purpose communication device on the inside of a room. Our passive solar window heating units will reduce your heating bills while increasing the life of your primary heating system. Depending on the design of your home, orientation of windows to the sun, and number of units you are using, your heating system may not operate at all on a sunny winter day. The solar window heating units sit behind the exist window glass and cover the lower sash (bottom section) of a double hung window. It uses solar chimney technology to pull cooler room temperature air vertically from the bottom of the unit over a corrugated metal plate which creates little chimneys. The chimneys ultimately increase the air flow over the solar heated metal plate thereby improving the heat output of the unit. Temperatures exceeding 130 degrees have been recorded at the top of the unit. Since the solar window heater sits inside an existing window, there are no objections from Homeowner Associations (HOA) Boards. The units are simple, lightweight, have no moving parts, and have an infinite return on investment. The bottom of the unit sits on the window sill and is held to the window frame by adhesive/nylon fasteners. Installation/removal is easy and takes about 15 seconds. The room side of the solar window heater is finished in a semi-gloss white paint. The basic unit has a high-gloss white finish on the main interior panel that can be used as a dry-erase marker board. A push pin mounting board covering half of the main interior panel can be purchased as an accessory. ....read more