Are you having trouble locating the air filter for your air conditioning system? You're not alone! It can be difficult to find the air filter in some HVAC systems, but with a few tips and tricks, you can easily locate it. The air cleaner is usually close to your home thermostat, in a return duct. In some systems, filters are located in the return air duct. This is the one that draws air from your space and returns it to the air conditioner's air handling system.
If you have a large system with multiple air handlers and return ducts, finding the filters can be a challenge. If the system has been operating in heating mode, the supply or outlet air ends of the ducts connected to the air controller will be warm to the touch and the inlet or return air ducts will be cooler. The filter is installed so that the arrow (and airflow) shows air moving through the filter TO the duct system (on a central air return grill) or TO THE air handler (for filters installed in the blower unit). In most homes, you'll find the air cleaner housing located right next to the air handler for your heating or cooling system.
The photo at the top of this page shows another conventional air filter located inside a vertical compartment of the air handler blower, in which case the filter was very dirty and blocked with debris. Households that have a lot of occupants and pets will likely notice that their air filters need to be changed more frequently. Start by looking for a source of debris near the central air return; continue to look for leaks that could lead debris to the return air duct system along any part of its length. Vertical air handlers may be an upflow unit having return air entering the bottom of the air handler or blower and air conditioner (cooled or heated) exiting the top of the unit.
They can help you locate air filters and show you how to change them, so that next time is easier. The air cleaner may be in one or more common air returns or in the air handler, or less commonly, in a slot in the return air duct near the air handler. MORE examples of where and how to look for filters in an air conditioning or hot air heating system include: It may be intended to hold an air cleaner against the inside face of that grill return air chamber door-cover at the bottom of the air handler. Knowing where your air filters are located and that you have found them all makes it easy to inspect your air filters and change them regularly during the cooling or heating season. Be sure to find all filters, as some systems have several filters and even several types of filters installed, such as a fiberglass or pleated paper filter, a washable filter, and an electrostatic air filter.
By following these tips, you should be able to easily locate your air conditioner filter. If you're still having trouble finding it, contact a professional HVAC technician for assistance.