If you have a central AC unit and you suddenly start to notice dust and debris coming out of your cooling vents, then this is a sure sign that you need to change your air filter. If you have already changed the filter within the last month or two, then a simple filter change may not be enough to cut down on the amount of dust that filters through your vents. There are several things you can do to help the dirty situation.
Invest In A Duct Cleaning
Dust, dirt, and allergens can get into your ducts in a variety of ways. Some debris will work its way right through your air filter. This is normal. Air filters attached to your AC system only remove some of the dust and debris from the air. It cannot remove all or most of the dust and allergens like a HEPA filter would, because this would require a filter with dense fibers that are closely woven together. This greatly reduces the amount of air that flows through the AC system and efficiency drops considerably.
When dust and debris move into the vents of your cooling system, they will often collect on the sides of the ductwork. Dust can fall into the vents from inside your home as well. Also, mold spores make up a portion of the debris that works its way into your ducts. The spores will multiply and come up through the vents as cold air moves by. This is a common problem if your AC only runs occasionally, because mold spores have the opportunity to multiply completely undisturbed.
A good way to cut down on the amount of dust that comes up through the vents is to invest in a duct cleaning. Cleanings should be performed every two to five years. Vacuum equipment is used during the process to force dust out of the vents. When the cleaning is performed, ask the professional to use a biocide in the vents. Biocides will kill microorganisms that run through the ductwork and cause mold and mildew to accumulate.
Add An Air Intake Filter
Fresh air must move through the AC system to cool your home, and this air is funneled through the indoor evaporator unit. Air is pulled from the exterior of your home or from the attic so it can be cooled. Air pulled from both of these areas can be incredibly dirty, and this can increase the amount of debris that enters your cooling ducts. To help cut down on some of this debris, install an air intake filter.
You will need to locate the air intake duct and follow it to find the intake vent. Once your locate the vent, either in your attic or outside the home, place your hand up against it when your air conditioning unit turns on. You should feel air sucking into the vent instead of moving out of it. The vent will likely be covered by a grate. Remove the grate and measure the inside opening. Purchase a narrow filter to fit just behind the grate.
If you notice a circular duct opening behind the grate, then a rectangular filter may not fit the duct properly. Invest in a ceiling plenum with a duct collar attachment. The plenum is a large rectangular opening where a filter can be secured. The rectangular space tapers to a circular opening, called the collar that connects to the end of the intake vent. The collar typically attaches easily with a few screws and the intake filter can be slipped into the plenum space when you are done. If the plenum sits outside your home, then make sure to invest in a cover to fit over the filter so it does not become wet.
