How to Determine the Air Flow Direction for a Furnace Filter
Here as you can see we have got your basic furnace filter. It seems real simple but if you don't install it properly it may not work so efficiently the way it should or was intended to work. As you can see on the front side of this filter it has got a reinforced mesh. The purpose of this mesh is if this filter ever tends to break down as your air is circulating through your furnace, coming from your house through your furnace this is intended so this don't break down and suck inside your internal parts of your furnace. The mesh stops this from happening. As you can see the opposite side of it is nice and clean since this is where your air comes through of course. Now one thing that people don't always recognize is there is an air flow pattern on these filters. If you don't install these properly it may not work the way it was intended to work so as you can see on this furnace filter air flow in, air flow out so as your air comes in to your furnace this is your cold air intake and this is where it brings air in from your furnace through your house and it reheats it so you'll always want to bring your filter so it is coming in and then it goes back into your furnace and then flows back out.