Choosing the Right Air Filter for Your HVAC System

Maintaining clean, healthy indoor air is a top priority for many homeowners and using the right HVAC air filter plays a big part in providing it. Follow this guide to help you select the right filter type, size and MERV rating for your home’s indoor air quality needs. 

When Should You Change Your Air Filter? 

The first thing to consider is how often you should replace the filter. The general recommendation for conventional residential filters is to replace them every 90 days for the average home without pets. If you have a furry friend, increase this to every two months. For homes with multiple pets or family members with allergies, your schedule should be as often as every 30 days. 

Choosing the Right Air Filter Size 

Not all home comfort systems are built the same, so major brands make air filters to fit different-sized slots. Buying the correct size provides a snug fit without air leaking past the filter. Here are a few tips to determine the right filter size: 

  • Check the current filter for a label listing the dimensions. 
  • Measure the filter slot. Check the height, width and depth for a snug fit without forcing the filter into the opening. 
  • Consult the HVAC manual, which should specify the filter size and type recommended for your system. 

Types of HVAC Air Filters 

Different filter materials and designs are available, and each is suited for different needs. Here are some common types: 

  • Fiberglass filters are the most basic and cost-effective option. Made from layered fiberglass strands, they trap larger particles that could settle on the equipment. However, they don’t filter small particles that are harmful to breathe, so don’t count on them to deliver industrial-grade indoor air quality. 
  • Pleated filters fabricated with light polyester or cotton folds offer a larger surface area to trap finer particles. 
  • Electrostatic filters employ self-charging fibers to attract and trap airborne particles. They come in both disposable and reuseable forms. 
  • HEPA filters offer impressive filtration. However, because they drastically restrict airflow, they are usually reserved for medical facilities, clean rooms and other commercial properties. If you prefer a HEPA filter in your residential HVAC system, work with a heating and cooling technician to determine compatibility. 

The MERV Rating System for Air Filters 

Minimum efficiency reporting value, or MERV, is the scale used to evaluate air filter efficiency. Ratings range from 1 to 20, with the highest numbers indicating a filter’s ability to capture increasingly finer particles. 

  • MERV 1-4 describe the simplest of filters, helpful for large particles including allergens, pollen, lint and carpet fibers. They offer minimal filtration but are cost-effective for simple applications without pets or allergies. 
  • MERV 5-8 are better suited for homes and commercial buildings where pet dander, mold spores, pollen and dusting aids need control. They balance cost and filtration equally, making them a popular choice among homeowners. 
  • MERV 9-12 apply to filters that can capture legionella, humidifier dust, auto emissions and more. They provide superior air quality to help relieve allergies or mild asthma symptoms. 
  • MERV 13-16 are considered top-of-the-line filters for residential use. They’re found in hospitals and any other industries where pure air is necessary. These designs trap bacteria, tobacco smoke and even certain virus particles. 
  • MERV 17-20 ratings are exclusive to HEPA filters, capable of trapping roughly 99.97% of particles down to 0.3 microns in size, such as lead dust, humidifier dust, asbestos fibers and other incredibly small particles. 

How to Make Your Selection 

When deciding on the right home air filter, focus on these factors: 

  • Household needs: Pet owners, people with allergies or asthma, and homes in dusty or high-pollution environments may do best using a filter with a higher MERV rating. 
  • System compatibility: Before you upgrade to a filter with MERV 12, make sure your HVAC system can handle it without hampering airflow. 
  • Filter thickness: 4- to 5-inch-thick filters usually work longer and offer stronger filtration than standard 1-inch filters. Just make sure your system is compatible. 
  • Cost vs. benefits: High-end filters cost more up front but need to be replaced less often and provide higher air quality. Make a rough estimate of the potential long-term savings and health benefits before you decide. 
  • HVAC professional’s advice: The best way to make an informed decision is to speak with an HVAC technician offering reliable advice based on your home’s system and air quality requirements. 

Breathe Easier with Ӱ Heating, Air Conditioning & Plumbing 

When you’re ready for a better air filter, let Ӱ Heating, Air Conditioning & Plumbing help you make the right selection. Our air filtration system installation service will protect your HVAC equipment and relieve asthma and allergy symptoms. We take pride in making a meaningful difference in your life and comfort with help from our personalized, professional services. For assistance with choosing the right air filter or other HVAC needs, please contact Ӱ Heating, Air Conditioning & Plumbing today. 

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