Posted: October 14, 2025
Maintaining a clean and efficient HVAC system starts with one of the simplest yet most important tasks: changing your air filter. A fresh air filter ensures that your heating and cooling equipment can run efficiently, keeps your indoor air cleaner, and helps prevent costly breakdowns.
The good news is that changing your HVAC filter is a straightforward job you should be able to do yourself. Here’s a step-by-step guide, along with some insights on why routine HVAC maintenance is so important.
Most air filters are found either behind a return air grille (often in a hallway or ceiling) or inside the air handler/furnace unit itself. Check your HVAC system’s manual if you’re unsure.
Once you’ve located the filter compartment, carefully slide out the old filter. Pay attention to the direction of the airflow arrows marked on the frame. This will help you install the new one correctly.
Look at the frame of your old filter to find the dimensions, such as 16x25x1. Filters come in a variety of sizes and ratings, so make sure you purchase one that matches your system’s requirements.
Insert the new filter into the slot, making sure the airflow arrows are pointing in the same direction as before, i.e., toward the blower motor. A snug fit ensures maximum efficiency.
For most homes, filters should be changed every one to three months. If you have pets, allergies, or live in an area with high dust or pollen, monthly changes may be best.
Changing your filter regularly is only the first step in keeping your HVAC system running smoothly. Professional maintenance ensures that all parts of your equipment are inspected, cleaned, and fine-tuned for optimal performance. Without routine care, dirt and wear can cause your system to work harder, leading to higher energy bills and unexpected breakdowns.
That’s where Harned Durham Energy can make a big difference. Our expert technicians provide comprehensive HVAC maintenance services that go beyond what a DIY homeowner can do. If you sign up for a service plan with us, you’ll enjoy peace of mind knowing your system is in good hands year-round. From seasonal tune-ups to emergency repairs, Harned Durham Energy helps you maximize the lifespan of your equipment and avoid costly surprises.
In addition to routing maintenance visits, if you enroll in a service plan with Harned Durham Energy, you’ll also gain benefits like priority scheduling and discounts on parts and labor—making it easier and more affordable to keep your home comfortable no matter the season.
Changing your HVAC air filter is a quick and simple way to protect your system, improve indoor air quality, and reduce energy costs. But don’t stop there—pair this easy DIY task with professional maintenance from Harned Durham Energy to ensure your system is always running at peak efficiency. With expert care and a customized service plan, you’ll enjoy reliable comfort all year long.
If you live in the Greater Lehigh Valley, contact Harned Durham Energy today to learn more or to schedule a maintenance visit. And ask about our service plans.
