Everything You Need to Know About Air Filters

We all know we’re supposed to replace the air filter in our home’s central HVAC unit from time to time. But air filter maintenance is actually one of the most commonly overlooked home maintenance tasks. Unfortunately, overlooking this important task can cause your system to work harder than it should or even interfere with the comfort levels in your home.

In this post from our heating and cooling experts at General Heating & Air Conditioning in Shakopee, MN, we’ll break down some of the most common air filter questions. Check out this guide and then give us a call to schedule your regular HVAC maintenance.

The Purpose of an Air Filter

The air filter in your HVAC unit performs a key role in your home’s indoor air quality and can directly impact the performance of your heating and cooling system. Particulate matter or indoor air particulates are constantly swirling around your home. They come in all shapes and sizes and can interfere with human health and restrict the flow of air through your home’s heating and cooling system.

The following are examples of particulates found in most homes:

• Microbial particles including fungi, viruses, and bacteria.
• Allergens like pollen, dust mites, dust, mold, and human and pet dander.
• Other types of dangerous particles like asbestos, smoke, and lead.

When your HVAC system is working correctly, it cycles air through your home’s ducts and circulates every particle that’s lingering in the air inside your home. Air filters catch and trap those particulates as the HVAC system moves air around your house.

How Your Air Filter Works

An air filter works much like the lint filter in a dryer. Just as lint filters collect lint, air filters trap and collect particulates as they pass through your HVAC system, leaving the air inside your home healthier. As the layer of particles builds up in your filter, the filter becomes less effective, making it harder for air to blow through your system.

If you don’t change your air filter regularly, your home won’t heat or cool effectively. This can add up to increased monthly heating and cooling bills. It also means your system has to work much harder, which can wear out the components on your heater and AC, leading to the need for furnace repair or an HVAC upgrade earlier than expected.

Choosing the Right Air Filter

The main difference between types of air filters is the materials used to purify your air from various pollutants. Individuals with pulmonary diseases, like asthma or allergies, should consider getting an air filter with a higher MERV rating. MERV refers to Minimum Efficiency Reporting Value, a term that describes the efficiency level of an air filter. Higher MERV ratings are more efficient.

Moreover, if you are a smoker, own a pet, or leave your door/window open often, a higher-rated filter will also be suitable for you.  Conversely, if you just need to remove pollutants or dust from the air, a lower-rated MERV filter can also work well. To choose the best-suited HVAC filter for your home, it is essential to learn about different filters and their unique features.

Fiberglass or Spun Glass Air Filters

As the name shows, these filters use spun glass or fiberglass. Also referred to as flat-paneled, they are one of the most common types of HVAC air filters due to their affordable price. However, these filters may not efficiently purify indoor air quality. They can usually remove only 20 percent of the particles of 3.0 to 10.0 microns in size. Generally, the particles in this size range are pollen, carpet fibers, and dust.

Pleated Filters

Pleated filters consist of fabric-based mediums made of cotton or polyester that are arranged in the form of folds and are responsible for increasing the filter's surface area. Air filters with more pleats are generally more effective as they can capture smaller particles, like pollen, mold spores, pet dander, etc. Pleated filters are slightly more expensive than spun glass air filters.

HEPA Filters

HEPA is the acronym for the term High-efficiency Particulate Air, and these filters can remove over 99.97 percent of pollutants and allergens present in the air, including pet dander, mold, dust, bacteria, viruses, and smoke particles. HEPA filters are more expensive than the others mentioned on the list, but their efficiency is remarkable.

UV Light Filters

This type of filter uses short-wave UV light to kill viruses and bacteria and eliminate strong odors in your home by disinfecting the air when it passes through the filter. However, UV filters have some disadvantages as well in that they might not be very effective for dust or allergen removal and are more suitable for advanced filtration mechanisms.

Electrostatic Filters

Perfect for folks with allergies, electrostatic filters use a mix of cotton and paper fibers to create static electricity that acts as a magnet to trap impurities. They are capable of efficiently removing allergens and purifying air dust.

Air Filter Maintenance and Health

Air filter maintenance is important for your family’s health, as well. When you change your air filter regularly, it can be effective at trapping pollutants and germs.

An air filter can help to reduce all of the following health concerns:

• Allergies
• Asthma
• Bacterial and viral infections

When to Change Your Air Filter

When it comes to the right time to change your air filter, there is no magic time that works for every home. Certain factors may influence the frequency of the need for changing your filter. For example, pet owners will need to change their air filters more regularly due to the presence of pet dander and fur. The amount of dust your home generates will also influence the need for an air filter change. If you live in a particularly dusty region, you may require air filter changes more frequently.

A good rule of thumb is to change your air filter at least every three months. However, if your air filter is particularly dirty when you change it, you may need to schedule your air filter changes more frequently. It’s also a good idea to check your filter more frequently when your system is in high use like during the hot summer months. To determine if your filter is dirty, simply hold it up in the light. If there is no light passing through the filter, it’s time to change it.

Here are a few reasons to check your air filter regularly:

• Most respiratory problems are due to contaminants.
• Dust is filled with dust mites, a common allergen. 
• Children inhale more particles than adults based on size.
• Energy costs go down when air filters are changed regularly.
• You can avoid untimely fan blower motor and compressor damage.

Contact Your Shakopee Heating and Air Conditioning Repair Experts

When choosing an air filter for your home, the best route is to ask your heating and air conditioning repair pros. At General Heating & Air Conditioning, we recommend using cheap air filters from anywhere they’re sold so you can change them more often. In our experience, the more costly filters are too dense and can plug up much faster. Changing your air filters regularly is your best bet for preventing untimely HVAC problems.

We believe in giving homeowners practical solutions that save them money. When you’re ready for HVAC maintenance or repair, give us a call. Contact us online or call us at 952-445-2820 to connect with a residential air conditioning expert to schedule your HVAC maintenance.