How Often Should You Change Your Furnace Filter?
February 2, 2026
How Often Should You Change Your Furnace Filter? (And Why It Matters)
One of the most common questions we hear from homeowners is about furnace filters: Which filter should I use? and How often should I change it?
While the answer can vary slightly from home to home, there are some general guidelines that can help keep your furnace running efficiently and reliably.
Which furnace filter should I use?
For our Lennox furnaces, we typically recommend using a MERV 8 or lower-rated filter. While higher-rated filters may sound better, they can actually restrict airflow. A more breathable filter allows your furnace to operate at full capacity without putting unnecessary strain on the blower fan or system components.
How often should furnace filters be replaced?
Under normal conditions, furnace filters should be replaced every 4–6 months.
However, several factors can shorten that timeframe.
- Pets in the home
- Pet hair and dander are quickly pulled into your return air registers. That buildup collects on your filter faster than you might expect, blocking airflow and forcing your furnace to work harder than it should.
- Candle burning
- Candles release soot into the air, and that soot is surprisingly dense. It can clog furnace filters much faster than normal household dust, reducing efficiency and air quality.
- Other factors
- Homes with poor ventilation or higher dust levels may also need more frequent filter changes.
Keeping up with filter changes is one of the simplest and most affordable ways to extend the life of your furnace, improve indoor air quality, and avoid unnecessary repairs. If you’re unsure which filter is right for your system or how often yours should be changed, the team at Wensink Heating & Cooling is always happy to help.
If you’d like help scheduling a clean and check or have questions about your furnace, give us a call. We always answer the phone.
Choosing a heating and cooling company isn’t just about equipment—it’s about trust. At Wensink Heating & Cooling Services, we believe in doing business the right way: with honesty, responsiveness, and personal service you can count on. As a locally owned and operated company, we take pride in serving our community and treating every customer like a neighbor, not a number. You Talk Directly to the Owners When you call Wensink Heating & Cooling Services, you won’t be routed through a call center, automated system, or answering service. Your call is answered by a real person—and often by one of the owners themselves. That direct connection means your questions are heard, your concerns are understood, and decisions are made quickly. There’s no middleman and no runaround—just clear communication with people who know the business inside and out. We Always Answer the Phone We answer all calls during business hours and do our best to answer most calls after hours as well. When you need help, you won’t be met with voicemail or a robot. You’ll speak with someone who’s ready to listen and help right away. Prompt, personal attention is a cornerstone of how we do business, because we know HVAC issues don’t always happen at convenient times. Same-Day Service When Possible When your heating or cooling system isn’t working, comfort can’t wait. That’s why we offer same-day service whenever possible. Our team works efficiently to diagnose the issue and get your system back up and running as quickly as we can. Your comfort—and your peace of mind—are always our top priorities. Honest Reviews, Real Feedback We don’t filter, pay for, or “clean up” our reviews. What you see online is genuine feedback from real customers who have experienced our work firsthand. We believe trust is earned through consistent, quality service—not polished testimonials or marketing fluff. Our reputation is built on showing up, doing the job right, and standing behind our work. At Wensink Heating & Cooling Services, we’re committed to being responsive, honest, and easy to work with—from the first phone call to the final result. If you’re looking for a heating and cooling company that values personal service and accountability, we’d be honored to earn your trust.
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