Bismarck, ND- With overnight lows dipping into the 20s, by now, just about everyone, even the most diehard homeowners have flipped on their heat for the season.

That’s also a time when many people replace their furnace air filter.
One and two inch filters are recommended to be changed about two months.
If you buy a five or six inch filter, that will likely be good for a year.
People who don’t change out the filter cause their furnaces to overheat when it starts up, which is called short-cycling.
“The air conditioner’s been running all summer and running the air through,” Jeff Hinz with Kirkwood Ace Hardware said. “So, people start the furnace and think, ‘hey, I just started, the filter should be fine.’ No. the air has been cycling through that filter all summer.”

Hinz also says a good habit is to take a sharpie and write the date on the side of the filter when you replace it to help you remember how long it’s been since it was changed out.