Furnace Myths: What’s True and What’s Not

NisAir Air Conditioning • October 24, 2025

Furnace Myths: What’s True and What’s Not

Furnaces have come a long way from those behemoths full of roaring fires that needed to be fed shovelfuls of coal. Now, they are almost sleek, quiet and amazingly energy efficient. Still, some myths about furnaces persist. Which ones are true, and which ones are not?

Some Things That Are Not True

There’s a surprising number of beliefs about home furnaces that just aren’t true. Here are some.

The Furnace Doesn’t Need Regular Checkups

Every appliance in your home needs a regular checkup by a professional, and that certainly includes your furnace. Ideally, your furnace should be checked at the start of every heating season. In between those checkups, it’s up to you to change its filter every month or every quarter and keep your senses alert for funny sounds, smells and diminished performance. Neglecting a furnace results in either expensive repair costs or an appliance that simply dies when you need it most.

You Should Hold on to Your Old Furnace

Holding on to your old furnace until the bitter end is tempting. However, a furnace that’s very much past its prime becomes less efficient. This will cost you money in the long run because you’ll be constantly calling your HVAC professional for repairs. It’s simply better to get a new furnace.

Closing the Vents Makes the Furnace More Efficient

Closing the vents in your rooms doesn’t make the furnace more efficient. It only makes it work that much harder and unbalances the air pressure in the ducts. This can cause your ducts to leak, which makes your HVAC system even more inefficient.

Things That Are True

As there are myths about your furnace that need to be debunked, there are other beliefs that are actually true. Here are a couple of them.

Modern Furnaces Don’t Explode

You’ve probably heard horror stories about furnaces that get so hot that they explode. The good news is that modern furnaces have all kinds of safety protocols to keep this from happening. Indeed, if it gets too hot, your furnace will just switch itself off.

A Furnace Can Have a 99% AFUE

Modern furnaces are so efficient that they can attain a 99% annual fuel utilization efficiency, or AFUE. However, your house has to be very energy-efficient. This means keeping registers and vents clean and sealing up leaks in your ductwork and drafts in your windows and doors.



Your furnace keeps your home comfortable during the winter months, and it can make up a good percentage of your energy bill. Because of this, it’s important to maintain it or replace it if it’s on its last legs. If you need heating replacement services, give our HVAC professionals of NisAir of Fort Pierce, FL a call.

Recent Posts

By Nis Air November 20, 2025
AC maintenance services in Port St. Lucie, FL keep your cooling system running efficiently through Florida's heat and humidity year-round.
By Corey Creekmore November 18, 2025
Along the Treasure Coast of Florida—where coastal humidity, salty air, and year-round warmth create unique demands on indoor comfort—working with HVAC experts is not just helpful, it’s essential. From historic Fort Pierce to vibrant Port St. Lucie and the thriving communities across Martin and St. Lucie counties, understanding the value of trusted HVAC professionals can mean the difference between consistent, healthy comfort and costly, stressful repairs. Why Local HVAC Experts Matter Florida’s subtropical climate presents constant challenges for air conditioning and indoor air quality. Homes and businesses face: Persistent humidity, leading to mold risks and unpleasant indoor stuffiness. Salty, coastal air that accelerates equipment wear and corrosion. Sudden heat waves, requiring fast and reliable cooling response. Seasonal changes, when efficient heating systems matter on cooler nights. Only experienced HVAC experts with deep regional knowledge can match solutions to these distinctive challenges—ensuring each system is installed, maintained, or repaired with Florida’s coastal realities in mind. What Sets HVAC Experts Apart Relying on HVAC experts—like the certified team at NisAir Air Conditioning—brings several critical advantages: In-depth diagnostics and problem solving, which catch minor issues before they escalate into expensive breakdowns. Tailored recommendations for system sizing, installation, and upgrades based on home size, layout, and local weather patterns. Advice on energy-saving strategies that work in the Treasure Coast climate, from strategic insulation to smart thermostat settings. Transparent communication on costs, service timelines, and expected outcomes—minimizing surprises. Their commitment to ongoing training and up-to-date licensing means that every repair or installation reflects both best practices and the latest industry standards. Signs You Need the Help of HVAC Experts Homeowners and businesses along Florida’s Treasure Coast often wait too long before consulting experts. Warning signs that signal the need for professional evaluation include: AC struggles to maintain comfortable temperatures, despite running constantly. Humidity remains high indoors, even with a new or powerful unit. Equipment makes odd noises, emits unusual odors, or trips electrical breakers. Energy bills climb unexpectedly without any lifestyle changes. Indoor air feels musty, indicating filtration or ductwork problems. If you experience any of these in Fort Pierce, Port St. Lucie, or Jupiter Island, calling HVAC experts fast can save money and prevent property damage. The Process: How HVAC Experts Restore and Protect Your Comfort From the moment you reach out, professional HVAC experts handle every step with skill and respect for your time: Comprehensive System Inspection: They review the entire HVAC setup, from the outdoor condenser to the indoor air handler and ductwork. Accurate Diagnostics: Specialized tools and years of experience enable a quick, precise identification of issues—no guesswork or unnecessary replacements. Clear Recommendations: You receive honest advice on whether repairs, upgrades, or full replacements will deliver the best long-term results, along with a transparent estimate. Expert Repairs and Installations: Only high-quality components and proven techniques are used, restoring cooling, heating, and air quality efficiently. Testing and Walkthrough: Every solution is double-checked, and you’re given practical tips on getting the most from your system. No matter if it’s a routine service call in Jensen Beach or an AC emergency in Stuart, the HVAC expert’s goal is always lasting comfort. The Importance of Preventive Maintenance The Treasure Coast’s climate requires proactive care to keep HVAC systems healthy and efficient. Maintenance by true HVAC experts includes: Seasonal tune-ups that ensure optimal operation before summer or winter peaks. Filter changes, coil cleanings, and checks for corrosion or refrigerant leaks. Adjustments to improve airflow, humidity control, and temperature consistency. Early detection of wear-and-tear or hidden system inefficiencies. Regular maintenance is especially important for homes near the coast, where salty air can corrode unprotected components quickly. Advancements Only HVAC Experts Understand Modern HVAC technology is rapidly evolving. Local experts are your source for: High-efficiency, environmentally friendly cooling and heating systems. Smart thermostats and connected devices for customized comfort and energy management. Zoned systems and variable-speed innovations that adapt to Florida’s shifting temperatures and humidity. Advanced air purification and dehumidification systems for healthier indoor air. Their up-to-date expertise ensures you benefit from the technology that makes sense for both your budget and your Treasure Coast lifestyle. Emergency HVAC Service: Rapid Help When Comfort Can’t Wait HVAC failures often strike at the worst times—during a weekend heatwave or suddenly on a humid holiday evening. Trusted experts in Fort Pierce and Port St. Lucie offer: Prompt, dependable emergency repair with 24/7 availability. Fully stocked service vehicles, minimizing wait time for replacement parts. Courteous technicians who treat your home like their own and explain every step they take. Peace of mind comes from knowing HVAC experts will be there when you need them most. Indoor Air Quality: A Specialty for Local Experts Florida’s humidity means comfort is about more than temperature. Odors, allergens, and excess moisture challenge families and businesses throughout the region. HVAC experts provide: Whole-home filtration systems to reduce allergens and airborne contaminants. Ductwork cleaning and sealing for more effective cooling and better air quality. Advice on balancing humidity and ventilation, especially in waterfront and historic properties. Protecting your family’s health begins with air handled by those who understand the Treasure Coast environment. Why a Local, Family-Owned Expert Makes All the Difference NisAir Air Conditioning’s long-standing presence across Martin and St. Lucie counties has built its reputation on: Decades of hands-on problem solving for every kind of Florida home and business. Personalized solutions, matching equipment and strategies to real-world local needs. A family business approach—transparent, supportive, and committed to total satisfaction. Whether you're upgrading your air conditioner, fixing a furnace, or looking for better air quality, local HVAC experts turn complicated decisions into simple, reliable comfort. Conclusion: Experience, Integrity, and Community Trust For anyone living or working on Florida’s Treasure Coast, the difference between just another HVAC contractor and true HVAC experts is clear. It shows in the quality of the installation, the trust in the advice you receive, and the comfort you feel year-round. With specialized knowledge, hands-on skill, and true care for the community, HVAC experts like NisAir Air Conditioning give homeowners and businesses everything needed for healthy, efficient, and enjoyable indoor living—today, tomorrow, and for generations to come.
By NisAir Air Conditioning October 24, 2025
5 Bad Habits That Impact Your Indoor Air Quality
By NisAir Air Conditioning October 24, 2025
Cool Comfort Anywhere: Zoned HVAC Solutions for Multi-Use Spaces
By NisAir Air Conditioning October 24, 2025
Tips New Homeowners Can Use to Maintain Their Home’s Heating System
By NisAir Air Conditioning October 24, 2025
How to Know If Your Heating System Is Near the End
By NisAir Air Conditioning October 24, 2025
With Regular Service, You Can Keep Your Cool
By NisAir Air October 24, 2025
When Cool Turns Hot: Why Your Air Conditioner Is Blowing Hot Air
By NisAir Air Conditioning October 24, 2025
How to Balance Temperatures in the Fall
By NisAir Air Conditioning October 24, 2025
Don’t Ignore It: Why Weak AC Airflow Signals Big Problems
Show More