How-To Guides · DIY & home
How to Change Your Furnace Air Filter (Which Way the Arrow Goes)
It's the easiest furnace job there is, and skipping it costs you. A dirty air filter can raise your energy bill, and even damage your equipment. Here's how to change it, following ENERGY STAR.
1. How Often
Check it once a month. If it's dirty, change it. Either way, change it at least every three months.
2. Step 1: Find The Filter
Your furnace manual shows where the filter goes. It's often in a slot near the furnace, or behind a return air grille. Slide the old one out.
3. Step 2: Get The Right Size
The size is printed right on the frame. Get a new filter that matches it exactly.
4. Step 3: Arrow = Airflow
Look for the arrow on the side of the new filter. Point it the way the air flows, toward the furnace, and away from the return grille.
5. Step 4: Snug Fit
Slide it in so it fits snugly, with no gaps. Air that sneaks around the filter isn't getting cleaned.
6. Leave The Rest To A Pro
That's the do it yourself part. For the rest, like the electrical and gas checks, have a contractor do a check up once a year, before heating season.
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Sources
Checked against the official sources above. Steps can change as apps update - tell us if something looks different: wischavenindustries@gmail.com