Do central air conditioners have filters? The answer is yes! Most central air conditioning units have two or more filters, which are designed to clean the air and ensure good air quality as the unit circulates between indoor and outdoor air. The air filter is usually located close to your home thermostat, in a return duct or right next to the air controller in your air conditioning system. Central air conditioner filters are typically made of spun fibreglass or pleated paper or cloth, enclosed in a rectangular cardboard frame. Fiberglass filters, which are the cheapest option, are usually about one inch thick and are common in older systems.
Newer models of central air conditioning use thicker pleated filters. Larger homes usually have more than one climate control system, so you should check every possible location to make sure you've found all of your air filters. For example, the Ruud Achiever, super-quiet, 80-foot air controller has a molded permanent air filter that slides down to the back of the unit when you look at it from the burner side. Additionally, someone may have added an air intake (yellow arrows) to improve the total air flow through the system, but extracting the return air that is located near the oil or gas burner of a furnace may do so.
Replacing your home's air conditioner filter will allow the unit to continue to blow cold air without interruption. The air controller draws air from the house through the return duct system and then blows it through the heating or cooling system and returns to the house through the duct system. Factors such as type of filter, size of house, quality of air, number of pets in household, how often you use your unit, and whether anyone in your family has allergies or certain medical conditions can all affect how often you need to replace your filter. Once you have located all of your home's air filters, document their locations for future building owners, occupants, or repairers.
Additionally, if you have a standard filter, you may not be able to replace it with a true HEPA filter because the ducts aren't designed to do so. Regularly replacing your home's air filters is one of the most important things you can do to keep your central air conditioner running efficiently. Heating, ventilation and air conditioning (HVAC) systems must work harder to move air through a filter, so not all systems are equipped to do so. The photograph shows a vertical or upward flow heating and air conditioning unit whose cooling section was mounted as a complement to a hot air oven.