Check your air filters! When was the last time you replaced yours? Home Depot has you covered and is offering up to 40% off select Honeywell Air Filters! They have tons of different sizes so check your furnace and see which one you need. Then make your purchase and opt to have it shipped FOR FREE!
Home Depot is also offering subscribe and save options (just like Amazon). So you can opt to purchase it through the subscribe and save option and save an additional 5% off your purchase.