Choose a high-performance model with quad motors, dual speed, quiet operation, small 'in-joist' bay ceiling installation , and less energy to draw more of the air. Flush the hot air out of your house, before you choose to turn on the Air Conditioning (AC)... if you even need it. With 140 watts of power — a light bulb or two worth, they use about 85% less electricity than your central AC.
The ROI Calculation is based on purchasing a 1 - 1.7 Cubic Feet per Minute (CFM) Fan. Each year, save over $100 and also reduce the maintenance needed on your AC. Also, considering the tax credits, this item could be significantly cheaper.
TAX CREDITS: The American Recovery and Reinvestment Act (ARRA) provides you with a 30% Tax Credit for Whole House Fans, also called Advanced Main Air Circulating Fans, that are put into service by the end of 2010. This tax credit item is only for existing homes, not new construction, that is your primary residence and it includes the cost of materials and installation. (3 KEY POINTS - #1: The tax credit cap is $1,500 on collective home improvement elements other than Geo-Thermal 'Ground Source' Heat Pumps, Solar Hot Water Heating, Solar Photovoltaic, and Fuel Cell systems - which each have no cap and are eligible through 2016. #2: The tax credits for exterior 'weatherization' improvements like windows, doors and insulation do not include the cost of installation! #3: If you reach the $1,500 cap in 2009, you are not eligible for additional tax credits in 2010.) Choose a Whole House Fan that meets these criteria to get the Tax Credit; and check products carefully, because in many cases an ENERGY STAR certification does not necessarily meet the tax credit requirements below:
• Must not constitute more than 2% of furnace's total energy use.