Installing a 4-inch furnace filter is a great example of why the way a filter is set up matters just as much as the filter itself. In many homes, a 1-inch filter is placed loosely in the ductwork with a small cutout, which often means it never seals properly. When that happens, air can bypass

If you’ve ever stood in front of your furnace and wondered why there are different efficiency ratings, you’re not alone. Most homeowners hear “80%” or “90%+” and assume it’s just a number on a sticker. In reality, that number has a lot to do with how your furnace is built, how much heat you actually