Why Your Upstairs Feels Hotter in Spring — Even Before Summer Arrives

If you’ve lived in Statesville, NC for long, you know spring weather can be unpredictable. One day might feel like winter, while the next afternoon feels like summer. These rapid temperature changes are common across Iredell County—and they can put extra strain on your HVAC system if it’s not operating efficiently. At Duncan Heating & Air Conditioning, we help homeowners stay comfortable through every season. Understanding how spring’s temperature swings affect your heating and cooling system can help you reduce wear and tear, improve efficiency, and keep energy bills under control. Why Spring Weather Is Tough on HVAC Systems Unlike winter or summer—when your system primarily runs in one mode—spring often requires frequent switching between heating and cooling. Your system may: Turn on and off more frequently Alternate between heat and air conditioning Work harder to maintain a consistent indoor temperature This process, known as short cycling, can increase wear on components like compressors, blower motors, and thermostats. Over time, this can lead to higher energy bills or unexpected repairs. Smart Thermostat Strategies for Spring One of the best ways to protect your HVAC system during seasonal transitions is to adjust how you use your thermostat. Here are a few simple strategies homeowners in Statesville can use: 1. Avoid Large Temperature Changes Setting your thermostat drastically higher or lower forces your system to work harder than necessary. Instead, adjust temperatures gradually. 2. Use a Programmable or Smart Thermostat Smart thermostats allow you to schedule temperature changes based on your daily routine. This prevents unnecessary heating or cooling while you're away. 3. Find a Comfortable “Middle Ground” Temperature In spring, many homes stay comfortable around 68–72°F. Keeping your thermostat in this range can reduce constant system switching. 4. Take Advantage of Mild Days When temperatures are comfortable outside, open windows to give your HVAC system a break. Don’t Forget Indoor Air Quality Spring also brings pollen, dust, and other allergens into the air. Even if your HVAC system is running properly, a dirty filter can circulate allergens throughout your home. To keep your air cleaner: Replace air filters every 1–3 months Keep vents and registers unobstructed Consider indoor air quality upgrades like air purifiers or better filtration These steps can make a noticeable difference for allergy sufferers during the spring months. Signs Your HVAC System May Need Attention Spring is also a time when underlying HVAC issues begin to show up. Keep an eye out for warning signs like: Uneven temperatures between rooms Higher-than-normal energy bills Strange noises when the system starts Weak airflow from vents If you notice any of these issues, it’s best to have your system inspected before the hot North Carolina summer arrives. Trust Duncan Heating & Air Conditioning for Year-Round Comfort  Since 1931, Duncan Heating & Air Conditioning has helped homeowners in Statesville and surrounding communities stay comfortable in every season. Our experienced technicians understand how local weather patterns affect HVAC systems and can help ensure your equipment is ready for whatever North Carolina spring brings. Whether you need a system check, repair, or expert advice on improving efficiency, our team is here to help. Call Duncan Heating & Air Conditioning today at 704-872-2431 or schedule service online to keep your home comfortable through the changing seasons.

As February winds down here in Statesville, North Carolina, we’re in that familiar in-between season. Mornings are still chilly, afternoons can feel like spring, and your HVAC system is working overtime to keep up with temperature swings. This is one of the most important — and often overlooked — times of year to make sure your heating and cooling system is running efficiently. At Duncan Heating & Air, we know this transitional period can put extra strain on your equipment. A little attention now can prevent unexpected breakdowns and help you stay comfortable as we head toward warmer weather. Why Late Winter Is Hard on Your HVAC System By the time February rolls around, your heating system has likely been running steadily for months. Add in fluctuating outdoor temperatures, and your HVAC equipment has to adjust frequently — switching on and off more often than it would during consistently cold weather. This constant cycling can: Increase wear and tear on components Reduce efficiency Drive up energy bills Lead to surprise repairs right before spring If your system hasn’t had a recent inspection or maintenance visit, now is a great time to give it some attention. Check and Replace Your Air Filter One of the easiest ways to protect your HVAC system and improve comfort in your home is changing the air filter regularly. During winter, filters often collect dust, pet dander, and debris from running heat. A dirty filter can: Restrict airflow Make your system work harder Increase utility costs Reduce indoor air quality We recommend checking your filter monthly and replacing it at least every 1–3 months, especially if you have pets or allergies. Prepare for Spring Temperature Swings Statesville weather can shift quickly from cold mornings to warm afternoons this time of year. Your HVAC system may still run heat at night but cooling during the day before long. To prepare: Test your thermostat settings and programming Make sure your system switches smoothly between heating and cooling Listen for unusual noises or short cycling Check vents and registers for proper airflow If something seems off, addressing it now can prevent a breakdown when you need cooling for the first warm stretch of the season. Don’t Forget Indoor Air Quality Late winter is also when many homeowners notice dry air, dust buildup, and allergy symptoms starting to appear. Your HVAC system plays a major role in maintaining healthy indoor air. Consider: Replacing or upgrading filters Cleaning vents and returns Installing a whole-home air purifier or humidifier Scheduling duct inspection or cleaning if needed Improving indoor air quality now can make a noticeable difference in comfort and health heading into spring pollen season. Schedule Preventative Maintenance Before the Rush Once the first warm days hit, HVAC companies get busy quickly with AC repairs and tune-ups. Scheduling maintenance in late winter helps you beat the spring rush and ensures your system is ready when temperatures rise. A professional tune-up can: Improve energy efficiency Extend system lifespan Catch small issues before they become costly repairs Ensure safe, reliable operation Stay Comfortable with Duncan Heating & Air Whether you need a seasonal tune-up, indoor air quality solutions, or a quick repair, Duncan Heating & Air is here to help Statesville homeowners stay comfortable year-round. Our experienced technicians understand the unique weather patterns of North Carolina and how to keep your system running smoothly through every season. If your HVAC system could use a little attention before spring arrives, now is the perfect time to schedule service . Your comfort — and your energy bill — will thank you.

Winter in Statesville usually brings mild daytime temperatures — but anyone who lives here knows the real surprise comes after sunset. Nighttime temperatures frequently drop below freezing this time of year, and that’s when many homeowners notice their heat pump working harder, running longer, or even switching to backup heat. If you’ve wondered whether your system is supposed to behave this way — the answer is yes… to a point. Let’s break down why heat pumps struggle in freezing weather and what you can do to keep your home comfortable and your energy bills under control. How Heat Pumps Actually Heat Your Home Unlike furnaces that create heat, heat pumps move heat from the outdoor air into your home. Even cold air contains heat energy — but the colder it gets outside, the harder your heat pump has to work to extract it. Here in Statesville, winter days often hover in the 40s and 50s — ideal heat-pump weather. But once temperatures fall near or below freezing overnight, efficiency drops and the system may rely on auxiliary (backup) heat to maintain your thermostat setting. Signs Your Heat Pump Is Working Too Hard During cold snaps, some changes are normal — but others signal a problem: System runs constantly without reaching set temperature Sudden jump in electric bill Outdoor unit covered in ice Frequent switching to emergency or auxiliary heat A properly functioning heat pump will occasionally enter a defrost cycle to melt outdoor coil frost. But heavy ice buildup or nonstop auxiliary heat means it’s time for a professional check. Tips to Help Your Heat Pump Perform Better This Winter 1. Don’t Crank the Thermostat Up Suddenly Large temperature jumps force the system into backup heat mode. Instead, raise the thermostat gradually. 2. Keep the Outdoor Unit Clear Leaves, debris, or snow restrict airflow and reduce efficiency. Keep at least two feet of clearance around the unit. 3. Change Your Filter Regularly Restricted airflow indoors makes your system work harder outside — especially during cold nights. 4. Avoid Using “Emergency Heat” Unless Necessary Emergency heat bypasses the heat pump entirely and uses only backup heating — which is much more expensive to run. 5. Schedule a Winter System Check A mid-season inspection ensures refrigerant levels, defrost controls, and airflow are all functioning properly when you need them most. Is It Time to Upgrade? If your heat pump is more than 10–12 years old, newer high-efficiency models perform significantly better in colder temperatures than older systems. Many modern heat pumps now operate effectively even below freezing — perfect for North Carolina’s unpredictable winter nights. Stay Warm Through Every Cold Snap Statesville winters may be moderate overall, but those freezing overnight temperatures can test any heat pump. A little maintenance and professional attention now can prevent comfort issues and high bills later. If your system is struggling this winter, Duncan Heating & Air is ready to help. Our local team knows exactly how North Carolina weather affects home comfort — and we’re here to keep your system running efficiently all season long. Call today or schedule service online — and stay warm, Statesville!

As winter settles in around Statesville and the temperatures drop, many homeowners naturally think about furnace tune-ups, filters, and thermostat settings. What is often less top of mind: indoor humidity — yet it plays a key role in comfort, health and HVAC performance during the colder months. Why humidity matters this time of year When outdoor air gets colder, it holds less moisture. As we bring that air inside and heat it, its relative humidity drops dramatically – often to levels that feel dry and uncomfortable. This has a handful of knock-on effects: Dry skin, scratchy throats and increased static indoors. Wood floors, furniture and window/door frames may shrink or crack from the dry air. Your heating system may run more often to compensate for the “dry-cold” feeling even when thermostat settings haven’t changed. Paradoxically, colder air with higher moisture content can feel warmer than dry air at the same temperature. How low humidity affects your HVAC system At Duncan Heating & Air Conditioning, we see how improper indoor moisture levels can challenge the system’s efficiency: When air is very dry, you might crank up the thermostat setting to feel warm — but your furnace is doing more work and your energy bills go up. Ductwork and vents may accumulate dust more quickly in dry air—clogging filters, reducing airflow, and stressing the system. If your system includes a heat pump or hybrid system, optimum performance often depends on a correct balance between heating load and indoor humidity. What “ideal” indoor humidity looks like For winter months in our region, a good target range is around 35 %–45 % relative humidity (RH). Too high (over ~50 %) worsens condensation risk on windows and in crawlspaces; too low (under ~30 %) leads to the dry-air issues above. Here are some practical steps we recommend to our neighbors at home and at Duncan Heating & Air Conditioning: Use a hygrometer – A small inexpensive device will tell you your current indoor humidity. If you’re below ~30% RH, take action. Introduce moisture – when needed Use a portable humidifier in high-use areas (bedrooms, living room). Place water-filled trays or plants in sunny spots to passively add humidity. Be mindful: Don’t over-humidify. If windows fog up and drip, humidity is too high. Seal the envelope of your home Close gaps in weather-stripping around doors and windows so the heater isn’t battling cold drafts and dry outside air. Ensure your attic and crawl space are properly insulated so the dry outside air isn’t pulling warmth (and moisture) out of the living area. Maintain your HVAC regularly Change filters monthly so airflow isn’t restricted — dry air moves fast but clogged systems still suffer. Have us inspect ducts and vents for dust-build up (which dry air accents). Ask us about integration of a whole-home humidifier system — if you’re finding portable humidifiers annoying or ineffective, this may be worth the investment. Adjust thermostat strategy You may find that you feel comfortable at a slightly lower thermostat setting when indoor humidity is balanced — meaning you’re warmer and using less energy. Consider using lower “away” settings during daytime, and raise it before you return, but keep humidity control active. Why choosing a pro makes the difference At Duncan Heating & Air Conditioning, we’ve been serving Statesville and surrounding areas since 1931 and know how local weather patterns impact homes. With experience, we can help you determine whether your heating system, ductwork, insulation or humidification setup needs an upgrade — not just patchwork fixes. A properly balanced home (heating system + humidity + insulation) means fewer cold spots, lower energy bills, less static and better comfort overall. More importantly: it means you’re not simply warming dry air — you’re creating a warm, healthy home environment. Ready to optimize your winter comfort? If you’ve noticed dry air symptoms, uneven warmth, or higher heating bills this season, let our team take a look. We offer: Humidity mapping and diagnostics Whole-home humidifier installation and integration HVAC tune-up with heating-season focus Duct and vent inspection Energy-efficiency consulting for insulation and sealing upgrades Call us at 704-872-2431 or schedule service through our website. Let’s make sure your home in Statesville stays warm and comfortable — the right way — this winter.

As the crisp mornings begin and leaves start to fall in the Statesville area, it’s the perfect time to shift your home-comfort strategy. The transition from summer cooling to fall heating presents unique opportunities (and a few hidden risks) for your HVAC system. At Duncan Heating & Air Conditioning, we want to help you make this seasonal shift smoothly, comfortably and cost-effectively. 1. Take advantage of moderate weather for airflow cleanup One of the best times to act is right now — when you neither need full-on cooling nor full-on heating. That means your system can be inspected, cleaned, and prepared before it’s under heavy load. For example: Remove leaves, pine straw, and other debris from around the outdoor unit so airflow isn’t restricted. Clear return vents, inspect filter access, and check that nothing is obstructed inside your home. This kind of proactive care helps your system run more efficiently and extends its service life. 2. Switch the thermostat but stay ready for temperature swings In fall, you’ll often toggle between the “A/C” and “heat” mode — sometimes in the same day. This means: If you have a heat pump, check that it switches correctly between cooling and heating modes. If you use a furnace, make sure the thermostat is set correctly and the system is ready to kick in when the chill arrives. By doing this early, you avoid that moment when you turn the heat on for the first time and it fails or performs poorly. 3. Replace or upgrade your air filters & check your indoor air quality Summer tends to fill HVAC filters with dust, pollen, and other pollutants. As the weather cools, you may see an increase in indoor allergens (leaves, mold from damp fall air, etc.). So: Change your air filter now — it’s a small cost for big benefits. Consider a higher-quality filter or an indoor air quality check to handle allergens and the transitional season’s humidity changes. Clean filters and good airflow reduce stress on your system and help maintain comfortable air. 4. Inspect your ductwork & vents for leaks and drafts During the summer your HVAC system’s load is high, so it’s easier to ignore inefficiencies. In fall, when you start using heating, weaknesses show up more clearly. What to do: Walk around your home and check for cold spots, drafty rooms, or vents that are blocked. Inspect exposed ductwork (especially in attics, crawlspaces, basements) for visible gaps or disconnected seams. Seal or insulate where needed so when heating starts, you’re not paying to warm up lost air. This improves comfort and lowers monthly energy costs. 5. Consider booking a fall tune-up to get ahead of winter You likely already know about spring checks for your A/C, but fewer homeowners remember a pre-heating season tune-up. Here's why it makes sense: A technician can spot wear from summer, check heating components, test efficiency, and make adjustments before you rely on the system on cold nights. You’ll reduce the chance of emergency breakdowns when temperatures drop and service queues are longer. It’s an investment in peace of mind and better performance for the season ahead. Why now matters Waiting until your first cold morning to act is risky. HVAC issues often start small but become costly fast — especially when demand ramps up. By prepping in this intermediate season, you: Extend equipment life span Avoid higher energy bills Maintain more even comfort levels Minimizing repair interruptions when you least want them Let Duncan Heating & Air Conditioning help If you’re in the Statesville, NC region and want to get ahead of the fall/hunting-season weather shifts, we’re here for you. Whether it’s clearing your outdoor unit, inspecting vents and ductwork, replacing filters, or scheduling your fall tune-up — we’ve got you covered. Contact us today to ensure your home stays comfortable, efficient, and ready for whatever the coming months bring.

As we head into fall in North Carolina, the days grow shorter and the nights chillier. It’s the perfect time to start thinking about how your HVAC system can work smarter—not harder—to keep you comfortable without sending your energy bills through the roof. At Duncan Heating & Air Conditioning, we’re always looking for ways to help our customers get more from their systems. Here are practical tips you can use right now to reduce your heating (and cooling) costs this season. 1. Leverage Natural Heat: Use the Sun Strategically Take advantage of sunny days: open curtains or blinds on south- and west-facing windows during daylight hours. This passive solar gain can help warm your home without turning on the heat. Then, as evening arrives, close them to retain the warmth. 2. Adjust Your Thermostat a Few Degrees Every degree matters. Lowering your thermostat by just 1–2 °F during cooler days (or raising it slightly when heating is in use) can yield noticeable energy savings. Use setback settings for when you’re asleep or away from home. A programmable or smart thermostat makes this easy. 3. Seal Drafts & Insulate Strategically Even a well-functioning HVAC system struggles if your home leaks air. Walk around your doors, windows, and baseboards looking for drafts. Use weatherstripping or caulk to seal gaps. Also, check attic and crawlspace insulation—adding a bit more insulation where needed is a relatively low-cost upgrade with long-term payoff. 4. Zone Wisely & Close Rooms You Don’t Use If your home has multiple zones or dampers, reduce conditioning in unused areas. Shut vents in guest rooms, basements, or storage spaces to focus heated air where it matters most. Just be careful not to close too many vents at once (which can affect system pressure). 5. Clean & Schedule Maintenance Now, Before Heating Demand Ramps Up Replace your air filters (if you haven’t recently). Clear debris from around your outdoor unit (if you have a heat pump) so airflow isn’t blocked. Make sure vents, registers, and returns are unobstructed by furniture or rugs. Schedule a professional tune-up: checking electrical, gas connections, combustion (if applicable), duct leaks, and system calibration can reveal small issues before they turn into costly repairs. 6. Use Ceiling Fans & Air Circulation to Your Advantage Many people think ceiling fans only help in summer—but they’re useful in fall too. Switch your fan’s direction to clockwise (low speed) to gently push warm air downward. This helps mix the air and can reduce the need to bump up the thermostat. 7. Monitor HVAC Performance & Watch for Inefficiencies Keep an eye on your energy bills, listen for odd noises, notice uneven heating, or detect higher humidity. If something seems off, call a technician to audit your system. Sometimes a minor adjustment or calibration can restore efficiency. Fall is a transition season—not quite cold, but cooler enough that the habits you set now can make a big difference in comfort and cost. With small changes like smarter thermostat use, sealing drafts, and proactive maintenance, your HVAC system can deliver the comfort you need without wasting energy. If you'd like professional help tuning your system or finding tailored energy-saving upgrades, Duncan Heating & Air Conditioning is here to help. Contact us today to schedule a fall performance check or ask about economical ways to make your heating system more efficient.

September may signal the start of fall, but in Statesville and across North Carolina, we all know the summer heat doesn’t just disappear overnight. Many homeowners still find themselves running the air conditioner well into September, which can keep energy bills higher than expected. The good news? A few simple adjustments can help you stay comfortable while keeping costs under control. At Duncan Heating & Air Conditioning, we’ve put together some practical tips to help lower your energy bills as summer lingers on. 1. Adjust Your Thermostat Settings A small change goes a long way. Setting your thermostat just a few degrees higher can make a noticeable difference in your energy use. For example, aiming for 76–78°F when you’re home and 80–82°F when you’re away helps reduce the strain on your system without sacrificing comfort. 2. Use Ceiling Fans to Your Advantage Ceiling fans don’t cool the air, but they circulate it so you feel cooler. This means you can raise your thermostat a degree or two without noticing much difference. Just remember to turn fans off when you leave a room—they only work when you’re there. 3. Keep Up with Filter Changes A dirty air filter makes your HVAC system work harder than it needs to. Replace filters every 30–60 days during heavy use. This not only saves energy but also improves indoor air quality for your family. 4. Seal Air Leaks and Improve Insulation Warm air sneaking in through cracks around windows, doors, or ductwork forces your AC to run longer. A quick weekend project—like adding weatherstripping or sealing duct joints—can make your home more efficient and lower energy bills. 5. Schedule an HVAC Tune-Up Preventative maintenance is one of the smartest ways to save money. A professional tune-up ensures your system is running at peak efficiency, identifies small issues before they become big repairs, and helps extend the life of your unit. 6. Take Advantage of Cooler Nights When evening temperatures drop, consider turning off your AC and opening the windows. Using natural ventilation, even for a few hours, can reduce your cooling costs significantly. Stay Comfortable, Spend Less As summer stretches into September, keeping your energy bills in check doesn’t have to mean giving up comfort. With these small steps—and the help of a trusted HVAC partner—you can stay cool and save money. At Duncan Heating & Air Conditioning, we’re here to help homeowners in Statesville and the surrounding area get the most out of their HVAC systems. Whether you need maintenance, repairs, or advice on improving efficiency, our team is just a phone call away. 👉 Contact us today to schedule your late-summer HVAC service and start saving on energy costs.

Summer in Statesville can bring soaring temperatures—and with them, rising energy bills and overworked air conditioners. At Duncan Heating & Air Conditioning, we believe in smart, energy-efficient solutions that keep your home comfortable without putting unnecessary strain on your HVAC system. Whether you're trying to lower your electric bill or extend the life of your unit, here are some practical tips to help you keep your cool without overworking your AC. 1. Close Blinds and Curtains During the Day Sunlight streaming through your windows may look nice, but it also heats up your home—fast. Keep blinds and curtains closed during the hottest parts of the day, especially on south- and west-facing windows, to block out the sun’s heat and reduce your AC’s workload. 2. Use Ceiling Fans Wisely Ceiling fans don’t cool the air, but they help you feel cooler by moving air across your skin. By running your ceiling fans counterclockwise in the summer, you can raise your thermostat a few degrees without sacrificing comfort. Just remember to turn them off when you leave the room to save energy. 3. Seal Leaks and Insulate Cool air escaping through poorly sealed doors, windows, or attic spaces makes your AC work harder. Sealing cracks and gaps, adding weatherstripping, and improving insulation are easy upgrades that make a big difference in efficiency. 4. Avoid Using Heat-Generating Appliances Midday Try to limit the use of ovens, stoves, dryers, and even dishwashers during the heat of the day. These appliances add unwanted heat to your home and force your AC to work overtime. Consider grilling outside or using smaller appliances like toaster ovens or microwaves in the evening hours. 5. Set a Smart Thermostat Schedule Smart thermostats allow you to control your home’s temperature more efficiently. Setting your thermostat a few degrees higher when you’re away from home can reduce strain on your system and lower your energy usage—without compromising comfort. 6. Keep Your Air Filters Clean A dirty air filter restricts airflow and makes your AC system less efficient. Checking your filters monthly and changing them as needed—usually every 1–3 months—can improve indoor air quality and help your AC run more smoothly. 7. Schedule Regular AC Maintenance Preventative maintenance is key to a long-lasting, efficient HVAC system. At Duncan Heating & Air Conditioning, we recommend scheduling a professional tune-up at least once a year to clean components, check refrigerant levels, and catch small issues before they turn into costly breakdowns. Stay Cool the Smart Way with Duncan Heating & Air Conditioning Keeping your Statesville home cool shouldn’t come at the cost of high energy bills or a worn-out AC. These small changes can go a long way toward making your home more comfortable and efficient. Need help improving your home’s cooling performance? Contact Duncan Heating & Air Conditioning today to schedule a tune-up , explore energy-saving upgrades, or get advice tailored to your home and budget.

At Duncan Heating & Air Conditioning, we know how frustrating it is when your AC system starts blowing warm air—especially during the peak of a North Carolina summer. If you’ve cranked down the thermostat and your home still feels more like a sauna than a sanctuary, there could be several reasons behind the problem. Here’s a look at some of the most common issues that could be causing your air conditioner to blow warm air, and what you can do about it. 1. Thermostat Issues Let’s start with the basics. Sometimes the issue is as simple as an incorrect thermostat setting. Double-check the mode. Make sure your thermostat is set to “cool” and not “heat” or “fan.” Check the set temperature. Someone in the house may have bumped it up higher than you realized. Dead batteries or faulty sensors in your thermostat can also cause communication issues with your AC unit. If everything looks correct but the problem persists, it may be time for a professional inspection. 2. Dirty or Clogged Air Filter A clogged air filter restricts airflow and can cause your system to overheat and blow warm air. Check your filter monthly and replace it at least every 1–3 months during the cooling season. Dirty filters can lead to poor airflow, frozen evaporator coils, and reduced efficiency overall. This is one of the easiest (and most affordable) problems to prevent. 3. Low Refrigerant Levels Refrigerant is the substance your AC system uses to absorb heat from inside your home. If the system is low on refrigerant (usually due to a leak), it won’t be able to cool effectively. Warning signs include: warm air, ice on the refrigerant lines, and hissing or bubbling noises. Solution: A licensed technician from Duncan Heating & Air Conditioning can locate and repair the leak, then recharge the refrigerant to proper levels. Refrigerant issues are not DIY-friendly, so give us a call if you suspect this is the problem. 4. Dirty Outdoor Unit (Condenser) Your AC’s outdoor unit releases the heat removed from inside your home. If it’s dirty or blocked, the system can’t release heat efficiently, and warm air may circulate back inside. Keep the area around your unit clear of leaves, grass clippings, and debris. If the coils are dirty, a professional cleaning may be needed. Regular maintenance helps keep this part of your system working properly. 5. Electrical Problems or Blown Fuses Electrical issues like a tripped circuit breaker or a blown fuse can shut down key components of your AC system, including the compressor. If the fan is running but the air isn’t cold , your outside unit might not be powered on. Don’t repeatedly reset breakers—call a pro to check things out safely. 6. Frozen Evaporator Coils When airflow is restricted—often due to a dirty filter or blocked vents—the evaporator coils can freeze over. Once that happens, your AC can’t properly cool the air. You may notice ice buildup on the coils or refrigerant lines . Turn the system off and allow it to thaw before restarting, then call a technician to prevent it from happening again. Need Help Fast? Call Duncan Heating & Air Conditioning If your AC is blowing warm air, it’s best to act quickly—what starts as a small issue can turn into a major repair. At Duncan Heating & Air Conditioning, we proudly serve Statesville, NC and surrounding communities with prompt, honest, and affordable HVAC service. Whether you need a quick repair, a full system tune-up, or a second opinion, we’re here to keep your home cool and comfortable all summer long. 📞 Call us today at 704-872-2431 🌐 Or schedule service online today!