When it comes to your home’s comfort, you’ve probably heard plenty of “tips” about how to save energy, lower your bills, or get the most from your heating and cooling system. Unfortunately, not everything you read—or hear from a neighbor—is true.
In fact, some of the most common HVAC myths can actually cost you money, reduce efficiency, and shorten the lifespan of your system.
At Harbin Heating & Air Conditioning, we’ve spent decades helping families across Tennessee and Mississippi stay comfortable year-round. We’ve seen firsthand how misinformation can lead to unnecessary repairs and higher utility bills. So today, we’re setting the record straight on some of the biggest HVAC myths still floating around.
Myth #1: You Need to Refill Your Refrigerant Every Year
This one is probably the most widespread myth we hear. Many homeowners believe that refrigerant (also known as Freon or coolant) needs to be “topped off” each year like you would add oil to a car.
Here’s the truth: Your HVAC system is a closed system. That means the refrigerant is sealed inside and should never escape—unless there’s a leak.
If your system is low on refrigerant, it’s not because it’s “used it up.” It’s because there’s a leak somewhere in the line or coil. Simply adding more refrigerant isn’t fixing the problem—it’s just a temporary patch.
The fix:
If you suspect your refrigerant is low, call a professional. At Harbin Heating & Air Conditioning, we locate and repair the leak before refilling the refrigerant, ensuring your system runs properly and efficiently long-term.
Myth #2: Setting the Thermostat to an Extreme Temperature Will Heat or Cool Faster
We get it—you come home from work on a 95-degree summer day, and your house feels like an oven. Your first instinct might be to crank the thermostat way down to 60°F, hoping it’ll cool off faster.
Unfortunately, that’s not how HVAC systems work.
Your heating and cooling system moves air at a steady rate. Setting the thermostat to an extreme temperature won’t speed things up; it’ll just keep the system running longer than necessary, wasting energy and driving up your bill.
The fix:
Set your thermostat to your desired comfort temperature and let your system do its job. Better yet, consider installing a Daikin One Touch Thermostat to automate temperature control and reduce energy waste.
Myth #3: Closing Vents in Unused Rooms Saves Energy
It might seem logical—if you’re not using a room, why heat or cool it? Many homeowners close vents in spare bedrooms or basements thinking it’ll save money. But here’s the problem: HVAC systems are designed to distribute air evenly throughout the home.
Closing vents disrupts that balance, creating pressure buildup in your ducts. That added strain can cause leaks, reduce efficiency, and even damage your blower motor or compressor.
The fix:
Keep vents open and unobstructed. If you want to control temperatures room by room, consider a zoned HVAC system or ductless mini-splits for targeted comfort and efficiency.
Myth #4: Bigger Systems Are Always Better
When shopping for a new HVAC system, it’s tempting to think a bigger unit will cool or heat your home faster. But “bigger” doesn’t mean “better.”
An oversized system will cool your home too quickly and then shut off, leading to short cycling. That not only wastes energy but also creates uneven temperatures and humidity problems.
On the other hand, an undersized system will struggle to keep up, running constantly and wearing out faster.
The fix:
The key is choosing a system that’s properly sized for your home. Our team at Harbin Heating & Air Conditioning performs detailed load calculations to ensure your unit is the perfect fit—not too big, not too small, but just right.
Myth #5: HVAC Maintenance Isn’t Necessary Until Something Breaks
Would you wait for your car’s engine to seize up before changing the oil? Of course not. The same principle applies to your HVAC system.
Regular maintenance keeps your equipment running efficiently, helps prevent breakdowns, and can even extend its lifespan.
Skipping tune-ups can lead to clogged filters, dirty coils, and airflow restrictions—all of which make your system work harder (and cost more to run).
The fix:
Schedule preventive maintenance at least twice a year—once in the spring for cooling and once in the fall for heating. Harbin Heating & Air Conditioning offers convenient maintenance plans to keep your system in top shape all year long.
Myth #6: Air Filters Only Need to Be Changed Once a Year
Another myth that can quietly cost you money. In reality, your air filter should be replaced every 1–3 months, depending on your home’s conditions.
Dirty filters restrict airflow, forcing your HVAC system to work harder. That means higher energy use and more wear on your blower motor.
The fix:
Check your filter regularly. If you have pets, allergies, or a dusty environment, you may need to replace it more often.
Myth #7: It’s Cheaper to Leave the Thermostat at the Same Setting All Day
Some homeowners believe it’s more efficient to keep the thermostat at one temperature all day long—even when nobody’s home—to “avoid system strain.”
The truth? That constant operation wastes energy. Modern systems are designed to handle temperature changes efficiently, so allowing them to rest during the day actually saves money.
The fix:
Use a programmable thermostat or smart system like Daikin’s One Touch Thermostat to automatically adjust temperatures when you’re away, then return to your comfort setting before you get home.
Myth #8: Duct Tape Works for Sealing Air Ducts
Despite its name, duct tape is not the right material for sealing air ducts. It dries out quickly, loses adhesion, and can even make leaks worse over time.
Leaky ducts can waste up to 30% of the air moving through your system—air you’re paying to heat or cool!
The fix:
Professional-grade mastic sealant or foil-backed tape is the correct choice for duct sealing. Or better yet, call the pros at Harbin Heating & Air Conditioning to inspect and seal your ducts properly.
Myth #9: Ceiling Fans Cool the Room
Ceiling fans circulate air—they don’t actually lower the temperature. However, they can make you feel cooler by creating a wind-chill effect on your skin.
That means you can raise your thermostat a few degrees while still feeling comfortable, which helps reduce your energy usage.
The fix:
Use ceiling fans to supplement your air conditioning, not replace it. In summer, run them counterclockwise to push air down. In winter, reverse direction to circulate warm air.
Myth #10: You Don’t Need a Professional for Installation
DIY HVAC installation videos might make it look simple—but it’s one of the most common (and costly) mistakes homeowners make.
HVAC systems require precise sizing, refrigerant handling, electrical connections, and airflow calibration. A small installation error can reduce efficiency, void warranties, or even pose safety risks.
The fix:
Always work with a licensed, experienced professional. As a Daikin Comfort Pro, Harbin Heating & Air Conditioning ensures your installation meets factory standards and performs flawlessly from day one.
Bonus Myth: All HVAC Companies Are the Same
This one hits close to home. We know homeowners have plenty of choices when it comes to HVAC service. But not all companies are equal.
Some focus on speed over quality. Others push unnecessary upgrades or skip crucial details during installation.
At Harbin Heating & Air Conditioning, our approach is different. We’re a local, family-owned company that treats every home like our own. We take pride in doing things right the first time—no shortcuts, no gimmicks, just reliable comfort backed by honest service.
How HVAC Myths Add Up
Each of these misconceptions might seem small on its own, but together they can lead to:
Higher utility bills
Frequent breakdowns
Shorter system lifespan
Reduced comfort in your home
The good news? A little knowledge goes a long way. Understanding how your HVAC system truly works can save you hundreds—or even thousands—of dollars over time.
The Harbin Difference
For decades, Harbin Heating & Air Conditioning has been helping homeowners across Tennessee and Mississippi make smart decisions about their comfort systems. We provide expert installation, repairs, and maintenance for:
Daikin heat pumps and air conditioners
Furnaces and ductless mini-split systems
Indoor air quality solutions
Duct repair and sealing
Smart thermostat upgrades
We’re proud to be a Daikin Comfort Pro, offering trusted products, professional installation, and customer-first service backed by years of local experience.
Final Thoughts
Don’t let HVAC myths drain your wallet. The truth is, your system works best when it’s properly maintained, correctly sized, and professionally serviced.
If you’ve been falling for one of these myths—or just aren’t sure if your HVAC system is running efficiently—it’s time to call in the experts.
At Harbin Heating & Air Conditioning, we’ll give you honest answers, reliable service, and lasting comfort you can count on season after season.
📞 Call Harbin Heating & Air Conditioning today at (731) 689-3651
📍 5910 Hwy 57, Counce, Tennessee 38326
Proudly serving homes across Tennessee and Mississippi, including Savannah, Pickwick, Corinth, Iuka, and Florence.
We’re here to help you stay comfortable, save money, and make smart choices for your home’s HVAC system—all year long.
