Consider a Whole-House Air Cleaner When a Filter Can’t Do the Job

Don’t assume that the standard air filter in your forced-air heating or cooling system will guarantee clean and healthy indoor air. Unless the air filter is rated as high efficiency, utilizing densely effective air filtration media, the filter likely won’t catch anything but the largest dust particles. While this will fulfill one main goal of air filtration, protecting sensitive components of your HVAC equipment, it won’t do much to clean the indoor air.

This is something to think about if you have one or more family members who are susceptible to allergies and other respiratory issues. More and more households have been considering a two-pronged strategy for ensuring indoor air quality – air filtration and air cleaning.

The Limitations of Air Filtration

In a typical forced-air central heating or cooling system, whether a combustion furnace, air-source heat pump or air conditioner, a standard flat-panel filter slots into a frame located between the ductwork and the furnace, AC or heat pump. Before air is drawn into the equipment to be heated or cooled, it flows through the filter. Depending on its type and grade, the filter will remove some amount of particulates from the air. While some air filters are designed to remove the vast majority of airborne particulates, this often has a negative result.

The same attribute that renders the highest-efficiency air filters so effective at cleaning the air also restricts the flow of air in your forced-air system. Dense filtration media – the ingredients that add up to effective filtration – slow the movement of air through the filter. That resistance forces your central heating or cooling equipment to work harder to draw air through the filter. This wastes energy, stresses parts (such as in the blower), and may lead to breakdowns. An overworked AC or furnace won’t last as long as one that’s operating as intended. Impeded airflow also can lead to poor air circulation in the home.

The good news is that most HVAC systems can be retrofitted to work with a high-efficiency air filter. The bad news is that this can be expensive. You could be better off – both financially and health-wise – with a whole-house air-cleaning system that works with your central heating and cooling system to clean the indoor air.

Consider an Air Cleaner

Multiple and varied technologies can be utilized in modern air-cleaning systems, with the most effective models combining methods to purify indoor air. The best systems can remove as much as 99 percent of airborne particulates from indoor air. While most whole-house air-cleaning systems work with the home’s central HVAC system to treat all of the air that circulates through the home, others work independently of the central cooling and heating equipment.

Electrostatic air cleaners are one cost-effective whole-house option for residential use. These systems resemble register vents, and are typically hidden in a return air box, installed non-obtrusively in a wall or ceiling. They don’t work directly with your forced-air HVAC equipment, so installation is relatively easy. As household air is drawn through the return vent, the system employs a polarizing process and activated carbon filter to trap gases and airborne particulates. Maintenance is simple, only requiring simple cleaning and replacement of the air filter every month or two.

Other Air-Cleaning Options

Other air-cleaning strategies that use electrostatic attraction to purify indoor air can be connected directly to the HVAC equipment. Similar to a standard air filter, this system is installed between the return ductwork and the air handler or blower. During installation, the technician should take care to seal connections tightly, to prevent air leaks. Many of these systems combine electrostatic technology with a high-efficiency particulate air/arresting (HEPA) filter.

Stand-alone air purifiers that employ HEPA filtration also can be effective, though they’re usually not effective for whole-house air cleaning in medium to large houses.

Many other air filtering options also are available employing various technologies and boasting different levels of effectiveness. They include gas-phase filtration, hybrid filters and ozone generators.

Research Your Options

As should be obvious from reading this article, which only presents a general overview of the topic, it’s important to perform deeper research, using authoritative sources, before deciding on the right air-cleaning strategy for your home. Plus it’s important to note that in many homes, a standard air filter really is the only thing you’ll need to provide sufficiently clean air. Your trusted Cincinnati HVAC contractor should be able to provide valuable advice on these issues.

Note on the Coronavirus

At this writing, research was mixed on how effectively various air-cleaning strategies can filter out the virus that causes COVID-19. No matter what sort of air cleaner or purifier you select, it’s still important to exercise safe sanitary and social distancing practices in the household, as recommended by the CDC and other authoritative sources, if there’s a concern about infection from guests or members of the household.