Changing My Furnace Filter: The Definitive Guide
Your home furnace is designed to circulate and distribute warm air throughout your home. As an added bonus, the air is also filtered along the way to reduce dust and improve your indoor air quality. However, many people don’t know how often to change a furnace filter, how to do it or which variety to choose. Check out this convenient guide that tackles these questions.
How Often Should I Change My Furnace Filter?When it comes to changing furnace filters, there are several factors to take into consideration. Here are some things to think about before it’s time for your next swap.
Filter VarietyDisposable fiberglass panel or electrostatic panel filters need to be changed every one to three months. Higher-quality pleated filters last anywhere from three to six months, while high-efficiency particulate air (HEPA) filters, which meet certain efficiency standards set by the United States Department of Energy, last many months.
Allergy StatusA cleaner filter helps alleviate allergy symptoms through the removal of more dust, pollen, bacteria and mold than an older, dirtier filter. If you or your family members struggle with allergies, change your filter every 20 to 45 days.
Number of PetsPet dander is also more efficiently removed from the air when your furnace filter is cleaner. The more pets you have, the more frequently you need to prioritize changing your furnace filter. A clean filter improves the air quality flowing through your home. If you have a single pet, your filter needs to be replaced at least once every 60 days. However, if you have multiple pets, plan to replace your filter at least once a month.
Home UseVacation homes that aren’t rented out on a nightly basis receive far less use, so the furnace filter probably only needs to be changed once every 6 to 12 months. If you live alone and don’t have any pets, changing a furnace filter is probably not needed as often as in full households. Let the filter be the guide, and always change the filter when it appears dirty.
Presence of a Filter GaugeThe indicator needle on the gauge tells you when it’s time to change a furnace filter. It senses the air pressure between the filter and the blower. If your HVAC system is equipped with this component, watch it carefully and know when to replace the filter.
Different Types of Furnace FiltersIt is important to choose the right furnace filter for your HVAC system. Filters are rated by their Minimum Efficiency Reporting Value (MERV), which indicates how fine of particulates are filtered from the air and how efficiently. The higher the MERV, the smaller the particles the filter is capable of catching and the more of them they catch. Here are the different varieties of furnace filters to be on the lookout for.
- Fiberglass – Thick-spun fiberglass filters are perhaps the most common type available. With an average MERV rating of 1 to 4, these filters are effective at keeping only large amounts of dust, dirt, large fibers and other obvious debris out of your furnace.
- Pleated – With a MERV rating between 5 and 16, these filters offer better filtration performance and, due to their pleated shape, more surface area for capturing airborne particles. Unfortunately, these filters are slightly more expensive to replace and need constant replacement to prevent clogging and degraded furnace performance.
- Electrostatic – Available in both disposable and washable forms, electrostatic filters rely on a built-in static charge to capture a variety of airborne pollutants, including mold spores, pollen and pet dander. Most electrostatic filters cost more than their pleated counterparts, however. Unfortunately, electrostatic filters carry an average MERV rating of between 1 to 4.
- HEPA – High-efficiency particulate (HEPA) filters are capable of removing up to 99.97 percent of airborne particles as small as 0.3 microns. However, these filters are more expensive and often require a custom enclosure and a blower fan capable of overcoming the filter’s added airflow resistance. If you have severe respiratory problems, this could be the right filter for your furnace. HEPA filters have MERV ratings of between 9 and 20, which is why they are used in hospitals, laboratories and other places that can’t tolerate dust and grime.
Steps for Changing a Furnace FilterHere is a step-by-step guide for replacing your furnace filter.
- Step 1: Cut the Power. Before you begin, cut off the power to your filter by shutting off the breaker. This step protects you from sustaining electrical shocks.
- Step 2: Find the Filter Compartment. Filters are typically located in the blower compartment of your furnace. There may be a section with a flip-open panel or a sliding door held in place with a removable finger screw.
- Step 3: Check your Filter. Pull the filter out of your furnace, and hold it up to the light. If you can’t see through it, replace it. If you are using a washable furnace air filter, follow the manufacturer’s recommendations for removing dust and grime before replacing it.
- Step 4: Install the New Filter. All air filters come with a convenient arrow on the side that indicates how air flow should move. Place your filter into your blower compartment in a way that the arrow points to the direction of the airflow. This important step allows your furnace to operate properly.