Changing Your HVAC Filter: Do's and Don'ts

Your HVAC air filter plays a major role in keeping your home comfortable. Here are some tips for properly maintaining your filter and some common mistakes to avoid.

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Changing an HVAC air filter

Your HVAC systems keeps you comfortable all year long, and the air filter plays a major role. As air flows through the system, the filter collects dust and other airborne particles, keeping the air clean. As time goes by, however, the filter clogs, reducing its performance. Here's what you should do to properly maintain your HVAC filter, and some common filter changing mistakes to avoid.

DO:

✅ Change your filter regularly. A dirty filter reduces HVAC efficiency and can potentially damage the system. It's important to swap out the filter regularly according to the manufacturer's instructions. Factors such as pets or dust from renovation work can clog filters faster. In such cases, check your filter more often and replace if needed.

✅ Consider the MERV rating. The Minimum Efficiency Reporting Value (MERV) measures how effectively an air filter captures and removes airborne particles — the higher the number, the more particles the filter traps. Choose a filter with a MERV rating that balances efficiency and airflow. For most HVAC systems, a MERV rating of 8 to 13 is best.

✅ Point the filter in the right direction. The furnace filter should face so that the airflow arrow printed on the filter points toward the indoor or blower motor, aligning with the direction of the air moving through the system.

DON'T:

❌ Buy cheap, low quality filters. Opting for cheaper filters may save money initially but can lead to higher costs in the long run due to reduced efficiency and potential damage to your HVAC system. Investing in high-quality filters offers better filtration and durability. Quality filters can improve air quality and prolong the life of your HVAC system.

❌ Use the wrong filter size. Installing a filter that doesn't fit significantly reduces its effectiveness. Even a small gap around the frame lets unfiltered air bypass the filter media completely — sending dust, allergens and debris straight into your ductwork and living spaces. Look for the size of the old filter or check the HVAC system manual before purchasing and installing a new filter.

❌ Try to clean and reuse disposable filters. Attempting to clean and reuse disposable filters can diminish their effectiveness and introduce more contaminants into your home. Stick to the manufacturer's instructions — if a filter is labeled as disposable, replace it rather than attempting to clean and reuse it.

❌ Neglect other filters in your home. Many homeowners focus on the main HVAC filter while forgetting about other devices around the home that use air filters, such as an air purifier. Keep a checklist of all devices in your home that use air filters and maintain a regular replacement schedule for each.

Dirty filters are a major cause of system failure. Changing filters regularly is a small investment in time and money that will make your home more comfortable and efficient, and it may save you some big headaches down the road.