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Types Of Air Filters

People sometimes expect their home’s indoor air to be cleaner than the air outdoors, but the opposite is often true. It’s common for households in Rockville, MD and the surrounding communities to have poor indoor air quality due to traces of allergens and pollutants and, in some cases, higher concentrations of airborne contaminants than outside air. Poor indoor air quality is why it is important to install a quality air filter in Rockville.

An air filter is a vital component within your home’s HVAC system. In this blog, we share what you should know about your air conditioning or furnace filter and how to choose the best one for your residence.

Why Is Your Home’s Indoor Air Quality Important?

It’s possible for your home’s air to have more pollution than outdoors because of the contaminants circulating through the property. People engage in many daily, unassuming activities that contribute to poor indoor air quality, including:

  • Smoking
  • Cooking
  • Cleaning with chemical cleaners
  • Lighting scented candles
  • Painting

Indoor air can also contain particles from furniture and construction materials. Viruses, bacteria, and mold are also in indoor air at various concentration levels.

Exposure to these particles can trigger a broad range of health issues. Depending on the allergens and pollutants you inhale, you could develop allergy-like symptoms, like a runny nose, itchy eyes, cough, or headaches. However, prolonged exposure to harmful airborne particles can lead to respiratory illnesses, heart conditions, and asthma attacks. You can enjoy clean, fresh air and minimize your risk of getting sick or uncomfortable inside your home by using a quality air filter.

What Are the Benefits of Air Filters In Rockville, MD?

As your HVAC system circulates the air throughout your home, it pushes air through an air filter on the unit’s intake vent. As air goes through, the screen traps airborne particles to reduce the amount of allergens circulating around your house. Some of the particles filters can catch include:

  • Pet dander
  • Dust
  • Mold
  • Lint
  • Smoke and smog
  • Pollen
  • Dirt

While air filters improve air quality, they also boost your household’s energy efficiency and comfort.

A dirty air filter won’t trap much debris, because the particles on the screen will restrict airflow from the HVAC system. As a result, the air conditioner or furnace will overwork itself to force air through the dirty pores. The overworked unit will then use extra energy to maintain the temperature on the thermostat despite the airflow restriction, leading to higher energy costs and reduced indoor comfort.

One of the primary maintenance tasks for heating and cooling units is air filter replacement. The longer you run the HVAC system with a dirty filter, the more likely it is to develop premature wear and tear. Many air conditioning and furnace problems are preventable if you change the filter regularly.

Homeowners should change their air filters at least once every three months. If you or someone in the household has asthma or another respiratory issue, like allergies, it may be best to replace the filter once a month for a cleaner environment.

What Are The Different Types Of Air Filters?

At Glenmont Heating and Air, we proudly offer various quality air filters in Potomac, MD and surrounding areas. Filters are available in several forms, with varying particle trapping abilities. Pleated and fiberglass filters are among the most common for Rockville residents, but they aren’t the only options.

Pleated Filters

Pleated air filters have folded polyester or cotton sheets within a cardboard frame. The material inside the frame has small pores to catch tiny particles to improve indoor air quality.

Since they can trap small particles, pleated air filters tend to be costly. Their small pores also create a higher airflow resistance, making it more difficult for HVAC units to push air through them.

Fiberglass Filters

A more affordable air filter option is the fiberglass variety. The screen has several fiberglass layers inside a metal grate and frame.

Unlike pleated filters, fiberglass air filters aren’t suitable for catching small particles. The screens can catch a little more than 15% of particles between 3.0 and 10.00 microns, like pollen and dust. They can improve your home’s indoor air quality, but not as efficiently as other screens.

HEPA Filters

High-efficiency particulate air filters are one of the best on the market. They remove over 99.95% of airborne contaminants, including smoke, dust, and bacteria.

HEPA filters are costly and unsuitable for some HVAC systems. Still, if you have an allergy or serious respiratory problem, it may be worth investing in an air purifier that takes HEPA filters for a healthy living environment.

Reusable Filters

A reusable or washable filter often looks like a fiberglass or pleated screen, but you can clean and reuse it. Though it costs more upfront to purchase a reusable air filter, it will save you money long-term because you won’t have to buy filters every 90 days.

Cleaning a washable filter is simple. Use a vacuum to remove dirt and rinse it to eliminate lingering impurities. You must let the screen dry fully before reinstalling it to prevent mold and bacteria from accumulating on the damp surface, which can reduce your home’s indoor air quality.

What Is the Importance Of A MERV Rating?

As you research different air filter types and brands, you’ll see they all carry a MERV rating. The minimum efficiency reporting value (MERV) rating is how the industry measures a filter’s ability to do its job.

The MERV rating scale goes from 1 to 20, with 20 being the most efficient. The higher the rating, the better the air filter will trap pollutants and allergens. For example, most fiberglass filters have a MERV of one to four. Pleated and HEPA filters have ratings of five to 13 and 17 or higher.

However, most homes should utilize air filters with 8-10 MERV. This rating will effectively catch particles and maintain good indoor air quality, while also keeping an efficient air conditioning and furnace system. Much like a clogged filter, high MERV filters have small filter pores and some HVAC units use more energy to push air through. We recommend leaving high MERV filters to necessary sterile buildings, such as hospitals.

Improve Your Home’s Indoor Air Quality With Glenmont Air Conditioning & Heating.

Besides installing air filters in Rockville, MD, our top-rated and well-trained technicians offer superior indoor air quality solutions to all customers, like air purifiers, electronic air cleaners, and humidifiers.

Our skilled crew has over 35 years of experience providing the best heating, cooling, and ventilation services to the community, including 24/7 emergency HVAC repairs. Your satisfaction is our guarantee and top priority. Call (301) 468-2665 to request an appointment with Glenmont Air Conditioning & Heating today.

Ways To Improve Indoor Air Quality

As we wave goodbye to the snow and cold weather, many Rockville residents ecstatically welcome the spring temperatures. However, the spring season is often paired with the arrival of allergy season. If you struggle with seasonal allergies, you are familiar with the tree pollen floating through the air and triggering allergy symptoms. The pollen outdoors and allergens inside your home can make for a very uncomfortable spring season for some, but the Glenmont Air Conditioning & Heating team can help! In this blog, we discuss ways to lower allergy symptoms and improve indoor air quality in Rockville, MD and surrounding areas.

What Allergens Are In Your Home?

Do you know what you are breathing inside your home? Harmful pollutants may be floating through the air and causing a variety of negative health impacts and symptoms. More often than not, indoor air is more polluted than outdoor air due to the lack of ventilation. Allergens can build up inside your home and cause your seasonal allergies to worsen. It is important to know which pollutants are in your home, because it helps a Glenmont technician find a helpful home solution. Below we have listed common indoor air pollutants in Rockville, MD homes according to the Montgomery County, MD Department of Environmental Protection.

  • Mold & Mildew
  • Volatile Organic Compounds (VOCs)
  • Dust
  • Pet Dander
  • Smoke
  • Radon
  • Asbestos

How Does Poor Indoor Air Quality Affect Your Health?

Most homeowners spend a large amount of their time at home, which means breathing in possible pollutants floating through the air. If your home has poor air quality, it could be affecting your health and causing uncomfortable allergy symptoms year-round. Many factors contribute to air quality beyond indoor pollutants, such as humidity. Low and high humidity can enhance negative health symptoms and increase potential air pollutants. Below are ways poor indoor air quality in Rockville, MD can affect your health.

  • Dry/Cracked Skin
  • Increased Susceptibility To Illnesses
  • Irritated Eyes
  • Runny Nose
  • Headaches
  • Dizziness

If you or someone in your home struggles with respiratory problems, such as asthma, poor air quality can heighten symptoms and lead to long-term health effects. We strongly encourage homeowners to maintain positive indoor air quality year-round, especially in the spring when allergy symptoms are present due to pollen!

How To Improve Air Quality In Your Home

While we can’t get rid of the pollen outside your home, we can help lower indoor air pollutants floating around your home. At Glenmont Air Conditioning and Heating, we offer a variety of indoor air quality services in Rockville, MD and surrounding areas. Below are services we can provide for your home to help you breathe easy each season.

  • Quality Air Filters
  • Humidifiers
  • Dehumidifiers
  • Electronic Air Cleaners
  • UV Light Systems

Quality Air Filters

The air filters in your home are responsible for filtering harmful pollutants before they enter the air you breathe. The two main types of air filters are fiberglass and pleated, and both have different ranges of minimum efficiency reporting values. (MERV) MERV measures the filter’s effectiveness to catch pollutants that pass through. The higher the MERV rating, the more allergens, small and large, the filter can catch and the cleaner your air will be. At Glenmont Air Conditioning and Heating, we offer a variety of quality air filters to help improve indoor air quality in your home. We can help identify the best air filter and MERV rating that suits your needs and remains in your budget.


Contrary to popular belief, humidity isn’t always a bad feeling! Good indoor air quality relies on 30-50% humidity in your home each season. During the winter and early spring months, humidity can be low in Montgomery County, MD and negatively impact you and your home. Humidifying systems can add extra moisture back into the air and contribute to overall air quality. Give us a call to learn more about installing a humidifier in Rockville, MD and surrounding areas!


While Maryland can have low humidity, Rockville can also see high humidity throughout the summer and early fall season. High humidity can encourage mold and mildew growth, which can cause uncomfortable health symptoms to you and other residents. Dehumidifying systems remove excess moisture in the air and can help control humidity levels throughout your home. Let a Glenmont technician install a quality dehumidifier in Rockville, MD to help improve indoor air quality!

Electronic Air Cleaners

Electronic air cleaners, also known as electronic air purifiers, work to remove a variety of airborne contaminants traveling through your air. The device traps large pollutants in a prefilter, while electrically charged filters catch smaller particles before they can circulate through your home. Electronic air cleaners in your Rockville home combined with traditional air filters can dramatically improve air quality and keep your air clean year-round!

UV Light Systems

UV light systems work to kill harmful pollutants such as mold, bacteria, and mildew. The system emits ultraviolet rays to destroy the allergens and keep them from negatively impacting your health and air quality. Pollutants such as mold can cause severe allergic reactions and risk long-term health effects. A Glenmont technician is happy to install a UV light system in Rockville, MD to keep you breathing easy in your home!

While we offer many indoor air quality services, there are other simple ways for you to improve indoor air quality, such as:

  • Maintaining Clean Air Filters
  • Grooming Pets Outdoors
  • Improving Ventilation In Your Home
  • Regularly Dusting
  • Use Natural Cleaning Chemicals

Your health is one of our top priorities at Glenmont Air Conditioning and Heating. We encourage homeowners to take action to improve indoor air quality, whether by simple maintenance tasks or installing a beneficial air quality device. Additionally, scheduling AC maintenance can further improve indoor air quality by allowing a trained technician to clean the inside and outside of your air conditioning unit. To schedule AC maintenance in Rockville, MD or learn about Glenmont’s indoor air quality services, give us a call!