Does a Dirty Air Filter Really Filter Better?

Particulate capture efficiency increases as the filter becomes dirtier; buildup in the fibers reduces the openings through which air passes and allows the filter to capture more particles. This is beneficial only to a certain extent. Engine misfires, rough idling, and hard starts can all be attributed to a clogged engine air filter. The dirty air filter restricts air supply to the engine, causing unburned fuel to form a soot residue that accumulates in the spark plug.

This fouls the spark plug (s) and decreases its ability to produce the spark needed for the combustion process. Replacing the affected air filter and spark plugs will restore your engine's performance. A clean air filter maintains airflow and keeps fuel economy right where it needs to be. A new air filter is white or off-white, while a dirty air filter will appear darker with visible dirt and debris.

Replacing the air filter before it becomes clogged ensures that you don't have to change the spark plugs. Advanced filters can last a little longer between cleanings and replacements, so check with the manufacturer for a recommended program. Over time, the engine air filter can become dirty and lose its ability to filter air entering the engine. If you start to hear coughing or clicking noises coming from the engine compartment, or if your vehicle vibrates excessively, it can be a symptom of a dirty air filter damaging a spark plug.

If your air conditioner has a reusable filter, you'll need to handle it with care to ensure it keeps your air conditioner running at peak efficiency. A dirty filter can cause allergens to build up in the duct system and will stay there for months. Most residential homes can accommodate air cleaners up to MERV 13, but you may want to consult with a professional HVAC technician before using any product other than MERV 9.A good air filter helps prevent dust and dirt from accumulating on all internal components of the unit; a bad one will cause additional wear and tear that can lead to serious maintenance problems in the future. From sizes to types, grades and more, here's everything you need to know about air filters. Sliding a wet filter back into the air conditioner only requires icing and other problems, and trying to dry the filter is likely to damage its delicate surface.

Dust and debris in the filter slow down airflow, forcing the heating or cooling system to work harder to maintain a comfortable temperature in your home. While manufacturers vary in their recommendations for how often the air filter should be changed, if you notice any of these signs that the air filter is dirty, it's time for them to inspect it. Regardless of why it happens, you might wonder if forgetting to regularly change your air filter is really that important. Air filters have a nominal cost compared to the cost of repairing or replacing your home's heating and cooling system.