The chill in the air means it’s that time of year again—so fire up the ol’ furnace and let the indoor heating season begin. But before you start cranking up the heat, you’ll need to clean or replace your furnace’s filters. After all, maintaining your heating system properly is one of the best ways to put a lid on sky high fuel bills.

If your filters are permanent, simply remove them and hose ‘em off outside. Let them dry completely before sliding them back into the furnace. But if your filters are disposable, don’t clean and reuse them—toss ‘em out! Then, head to the nearest hardware store to purchase a few new ones.

Just keep in mind that “bargain” filters are less efficient and need to be replaced more often, so don’t automatically reach for the cheapest one on the shelf. And if allergies are a problem in your family, then spend the extra money and buy filters that have the highest MERV (Minimum Efficiency Reporting Value) you can find. You’ll breathe a whole lot easier because these hardworking helpers will trap lots of sneezy, wheezy pollen and dander.

For more solutions that’ll cool down the high price of heating, check out my Insider Secrets book—FREE for 21 days. It’s filled with terrific tips for just about any problem that crops up around your home.