Air Filter Guide
Air filter is an essential part of an air conditioner. They are commonly found in the return air duct or grille of the air handler.
The air filters of an air conditioner are usually placed in specific slot that can be easily accessed, which is typically on any side of the return air part of the unit, depending on the type of system.
The air filters of an air conditioner serve two main functions:
- They protect your unit by screening out dirt particles that affect the efficiency and performance of the system, especially when they begin to clog the internal components, restrict airflow, and force the system to work even harder and use more energy in the process.
- They help keep your indoor surroundings free from airborne pollutants and viruses that affect the quality of air inside your home and might cause some health issues for your family.
In a mini split system, the outdoor unit that is placed outside the house is connected to the indoor unit which is mounted inside your home by a set of piping and wiring systems that are usually passed through a small hole in the wall (usually just a 2 ½-inch hole or a 3-inch hole), linking both units as one single system. The pipes are usually the cooper tubing called line set or refrigerant lines, while the wires are usually the electrical wiring system connects the unit to a power outlet.
Types of Air Conditioner Filters
The demand for better indoor air quality and the widely popular adoption of an array of guidelines and requirements for air filtration technologies have consequently pushed the production of enhanced air filters for air conditioners.
Today, you’ll find that there are many kinds air filters for HVAC systems. Some air filters can be washed and reused while others need to be occasionally replaced.
Basically, air filters vary in so many ways, but more specifically, in terms of type of filtration method, material component, appearance, application, and filtration capability.
For your air filter options, here are some types of commonly used air filters:
Fiberglass air filter
A very common type of air filter, a fiberglass filter is usually made of layered fiberglass and reinforced with some metal mesh or grating for support. This works great in screening out large particles.
Disposable air filters
Considered as economical, disposable air filters can be of any type (pleated, fiberglass, etc.), useful in all kinds of filtration, and applicable for residential or industrial applications. The only drawback is, while these filters are cost-effective, they need to be disposed of immediately when no longer effective. Nonetheless, they certainly work wonders if you’re using it for light duty air filtration.
Washable air filters
Highly effective in blocking air pollutants, washable air filters are obviously cost-effective. You just need to clean them regularly. You can simply wash them with water—no hassles at all and the best thing is, you’ll no longer need to worry about costs related to air filter replacement. As long as you are able to maintain their quality, these filters can last and be useful for many years.
HEPA (high-efficiency particulate air) filters
Considered one of the most effective air filters, HEPA filters are made of fiberglass fiber mats and popularly used in sensitive filtration applications, which are typical of what is needed in medical facilities where containment of airborne particles is very important. In home application, this is very effective in ensuring that you’re protected from airborne viruses, especially if someone in your family suffers from allergies. HEPA filters can effectively trap and screen out at least 99.97% of airborne pollutants.
Electrostatic air filter
This is a washable air filter that is known for having very little impact on airflow. It works through electrostatic attraction or by using static electricity in removing particulate matter in the air. While one of the biggest drawbacks of this filter is their capability to generate ozone, it remains one of the best furnace filters available.
Pleated air filters
Also called extended surface filter, pleated air filters consist of pleated fabric (cotton or polyester) and is deemed one of the most efficient in removing small airborne contaminants. The pleats or the folded fabrics enable the air to effectively and easily pass through, a characteristic that makes pleated air filters highly efficient.
Ionic air filters
By using negatively charged ions to attract airborne particles, ionic air filters are certainly one of the most innovative air filtration technologies. They purify indoor air and remove a high percentage of air pollutants inside your home or any commercial facility.
Carbon air filters
A new air filtration innovation using old technology, carbon air filters are highly effective in removing airborne pollutants and deodorizing air. It works through adsorption or by using oxygen to activate carbon (basically a charcoal), enabling it to absorb the vapors that cause bad odors through its highly absorbent pores.
UV light air filters
By utilizing the reaction generated from the exposure of titanium dioxide to an ultraviolet light, UV light air filters are able to neutralize and eliminate airborne particles.
MERV: Measuring the Efficiency of Air Filters
With so many methods of air filtration, the American Society of Heating, Refrigerating and Air-Conditioning Engineers (ASHRAE) took the initiative of providing a rating system that evaluates, judges, and rates air filters in terms of their capability to filter air. Technically, it means how effective the filter in screening out airborne particles. This measuring tool is called MERV or Minimum Efficiency Reporting Value.
MERV ratings range from 1-20, with one being the lowest and 20 the highest. Each rating says about a particular type of contaminant that can be controlled and a specific application. Carpet fibers, for example, is assigned with the lowest rating 1, and the filter is suggested to be best to use for minimal filtration work in a residential environment. The highest rating 20, on the other hand, pertains to highly harmful compounds from hazardous chemicals.
One thing that you should remember is that the highest the MERV rating, the smaller the size of airborne particles that a filter is capable of removing.
Now, here’s a caveat: When you’re choosing for a good air filter for your AC unit, always remember that the higher MERV is not always the most ideal. High-MERV filter usually means you’re using a filter with very small breathing room, which affects the airflow of the unit.
To effectively choose the right filter with the correct MERV for your system, you need to consider the specific environment that you want to cool. Your HVAC contractor would be a great help in this aspect if you’re not sure what to choose.
AC Air Filter: Everything Boils Down to Safeguarding Your Health
Believe it or not, the air you breathe inside your home is more polluted than the air that you get outside—at least 2 to 5 times greater, says the Environmental Protection Agency.
Airborne viruses that occasionally puts you under the weather is just one of the many pollutants that affect the air quality of your home. You can include on the list your pets’ dander, the exhaust fumes from your kitchen, toxic substances from the cleaning products that you use at home, tobacco smoke, dust mites, pollens from plants, molds, and bacteria among others. The lack of fresh air supply that enters your air conditioned home only aggravates the buildup of these pollutants. Not surprisingly, EPA declared indoor air pollution as one of the top five environmental health risks.