Now that winter is here one of the things that you should look to replace is your air conditioner filters because of all the dirt and and allergens that have built up over the summer months. Since you are inside more and not opening the door as much having a clean air filter is essential in keeping your indoor clean and helping to prevent any air quality issues. Plus it could even help in your overall heating costs because your air is flowing better through the home and allowing your house to stay at a more constant temperature.