BTU stands for "British Thermal Unit" and measures the heating or cooling capacity of a furnace or air conditioning unit. Enter your homes square footage to see how many BTU's are required to adequately heat or cool it.
Enter the square footage of your home (or room) and press Go.
This calculator is for estimating capacity only, and does not give exact equipment capacities for your home.
These replacement filters will fit into a Honeywell air cleaner requiring a 20" x 20" x 4" filter.
In 2002 Alpine Home Air Products became the first company to sell heating, air conditioning and indoor air-quality products online. We have proudly served hundreds of thousands of customers, helping them save time and money by buying their products direct.