How to Reset Air Conditioner When It Stopped Working

Premier Systems
August 30, 2023

Do you find yourself in the middle of a sweltering summer day, and your trusty air conditioner grinds to a halt? Before you dial your excellent AC maintenance service in Bozeman, MT, you can try a few easy tricks to reset your AC. 


Keep reading and learn how to reset air conditioner units. You can also call the Premier Systems crew at 406-300-4258 for help from our AC specialists. We make it a breeze to get your AC back in action quickly.


Hit the Reset Button

Almost every modern air conditioner has a reset button to restart the system if it shuts down. It's typically red, and you can find it near the motor housing. Some AC models might have it concealed beneath the plastic cover, so don't panic if you can't spot it right away.


Check your unit's manual for details on the button's location. Once you find it, give it a firm press. This fix often works for air conditioners that have shut down due to power outages or sudden disconnections.


Reset the Isolator Switch

An isolator switch, sometimes called the disconnector, is a safety device that controls the flow of energy between an air conditioner and the main electrical supply. When technicians conduct AC maintenance or repairs on your unit, they use the isolator switch to shut off the power supply, preventing any unintentional shocks or accidents while tinkering with the system.


To reset your air conditioner using the isolator switch, turn the lever, wait for half an hour, and then switch it back on. This period allows the device to discharge accumulated electrostatic charge and return to its default settings, potentially fixing your air conditioner.


Reset the Circuit Breaker

The circuit breaker keeps your electrical system safe from damage due to power surges. When it senses a short circuit or overload, it promptly "trips" or cuts off the power to prevent damage. So if your AC stops working, it's time to find the circuit breaker — you may need to simply reset the AC circuit switch.


Head over to your property's breaker box; it's usually a gray metal box situated in a utility area like the basement or garage. Open it up, and look for the switch dedicated to the air conditioner. If it's flipped to the "off" position or somewhere in the middle, you've found the culprit.


Flip it back to the "one" position and try your AC again.


Check Your Thermostat

When learning how to reset air conditioner systems, don't forget about the humble thermostat! As an integral part of your HVAC system, the thermostat controls the temperature according to your comfort level. However, a glitch in this device could throw your entire air conditioning system out of order.


Set your thermostat at your desired temperature, and make sure it's in cooling mode. If all settings look good, but the AC refuses to kick in, you might need to reset the thermostat.


Most modern designs have a reset button; press that and see if the system starts cooling your home again. For older models, you may need to remove the batteries and reinsert them after a minute — this will typically reset the device.


Do You Need Expert AC Assistance?

Even with all the clever troubleshooting, your air conditioner may remain stubbornly silent, refusing to deliver cool air. That's when you know it's time to call a technician. Here are a few other signs that it's time to call in the professionals:


  • Persistent noises: If your AC unit creates more noise than normal, it's a clear symptom of underlying complications. Rattling, buzzing, or humming noises all indicate issues that require expert attention.
  • Poor airflow: Even when your unit seems active, if the air from your vents wouldn't blow out a candle, you've got a problem. It could stem from ductwork or fan issues.
  • Unpleasant smells: Foul or pungent odors could point towards mold, while a burnt smell might indicate a problem with the wiring.
  • Water leaks: Constant moisture can damage your property and even lead to serious structural issues. Reach out to an HVAC professional as soon as possible.


Call Bozeman's AC Experts: Premier Systems

We hope our guide has helped you learn how to reset air conditioner units without breaking a sweat. Our team at Premier Systems is always at your service, ready to troubleshoot and fix any HVAC concern — from a light flickering in an AC unit to a complete system failure.



Give us a call at 406-300-4258 today to schedule service.

June 1, 2026
5 HVAC Problems Homeowners Notice During Montana's Rainy Days Rainy weather can be a welcome break from the summer heat, but it can also reveal hidden issues with your home's heating and cooling system. Increased humidity, fluctuating temperatures, and excess moisture can all impact your HVAC system's performance. If you've noticed your home feeling less comfortable during rainy weather, your HVAC system may be trying to tell you something. Here are five common HVAC problems homeowners experience during Montana's rainy days and what you can do about them. 1. Excess Indoor Humidity One of the most common complaints during rainy weather is a home that feels damp or sticky, even with the air conditioner running. Your HVAC system does more than cool the air—it also removes moisture. If your system isn't properly dehumidifying your home, indoor humidity levels can rise quickly. Signs of High Indoor Humidity: Sticky or clammy indoor air Condensation on windows Musty odors Increased allergy symptoms If your home consistently feels humid, your air conditioner may need maintenance or your system may be improperly sized for your home. 2. Musty Smells Coming from Vents Rain and humidity create the perfect environment for mold and mildew growth. If you notice a musty odor when your HVAC system turns on, moisture may be collecting somewhere in the system. Common causes include: Dirty evaporator coils Clogged condensate drains Mold growth in ductwork Excess moisture around the air handler Ignoring these odors can lead to reduced indoor air quality and potential health concerns for your family. 3. Reduced Airflow Rainy weather can expose airflow issues that may have gone unnoticed during drier conditions. Dirty air filters, clogged coils, or ductwork problems can restrict airflow and make it harder for your system to maintain comfortable temperatures. Watch for: Weak airflow from vents Rooms that won't cool evenly Longer run times Higher energy bills A professional HVAC inspection can quickly identify and resolve airflow problems before they become major repairs. 4. Water Leaks Around Your HVAC Equipment Many homeowners are surprised to find water pooling near their indoor HVAC unit during rainy periods. While it may seem like rainwater is entering the system, the issue is often related to a clogged condensate drain line. Your air conditioner removes moisture from the air, and that water needs somewhere to go. When drain lines become blocked, water can back up and leak around your equipment. Don't ignore water around your HVAC system. Left untreated, it can damage flooring, walls, and even the unit itself. 5. Thermostat and Electrical Issues Heavy rainstorms can sometimes cause power fluctuations that affect HVAC controls. If your thermostat isn't responding properly or your system cycles on and off unexpectedly after a storm, electrical components may have been affected. Common warning signs include: Blank thermostat screens Inconsistent temperatures System short cycling Failure to start If you notice these symptoms after severe weather, it's best to have a technician inspect the system to prevent further damage. Keep Your HVAC System Ready for Any Weather Montana's weather can change quickly, and your HVAC system needs to be ready for everything from summer rainstorms to humid days and temperature swings. Regular maintenance helps identify small problems before they become expensive repairs. A seasonal HVAC tune-up can: Improve system efficiency Reduce humidity issues Prevent unexpected breakdowns Extend equipment life Improve indoor air quality Schedule Your HVAC Inspection Today If you've noticed musty odors, humidity problems, weak airflow, or water leaks during recent rainy weather, don't wait for the problem to get worse. Our experienced technicians can diagnose the issue and help keep your home comfortable no matter what the forecast brings. Contact us today to schedule your HVAC inspection and ensure your system is ready for Montana's changing weather.
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Wildfire season has become an increasingly common part of life in Southwest Montana, especially for homeowners in Bozeman, Belgrade, and Four Corners. While the smoky haze outside is easy to see, what’s happening inside your home is often less obvious. Many people assume that simply closing windows and doors will keep them safe—but wildfire smoke can still enter your home and impact your indoor air quality (IAQ) in ways that affect both comfort and health. Why Wildfire Smoke Indoors Is a Serious IAQ Concern Wildfire smoke is made up of extremely fine particles called PM2.5, which are small enough to pass through tiny openings and even some standard HVAC filters. Once inside your home, these particles can circulate through your ductwork and linger in the air. For homeowners in our area, poor indoor air quality during wildfire season can lead to: Coughing, sneezing, and throat irritation Headaches and fatigue Aggravated asthma or allergies Increased strain on your HVAC system Without proper filtration and system maintenance, your home’s air may not be as clean as you think. How Smoke Affects Your HVAC System Your HVAC system plays a major role in managing your indoor air quality —especially during wildfire events. When smoke enters your home, your system can either help remove harmful particles or unintentionally spread them throughout your space. If your system isn’t equipped with the right components, you may experience: Reduced filtration of fine smoke particles Dirty ductwork circulating contaminants Increased wear and tear on system components Decreased efficiency and airflow This is why homeowners across Bozeman and Belgrade are upgrading their systems to better handle wildfire smoke conditions. HVAC Solutions to Improve Indoor Air Quality During Wildfire Season The most effective way to protect your home’s air is through professional HVAC solutions designed specifically for indoor air quality in Four Corners, Belgrade, and Bozeman. Upgrade to HEPA or High-Efficiency Filters Standard filters aren’t designed to capture the smallest smoke particles. Upgrading to HEPA filters or high-MERV rated filters allows your system to trap significantly more airborne contaminants, improving your IAQ immediately. Install Whole-Home Air Purification Systems Advanced air purification systems integrate directly into your HVAC system to continuously clean the air as it circulates. These systems are especially effective during wildfire season when outdoor air quality is poor for extended periods. Add an Air Scrubber Air scrubbers go beyond traditional filtration by actively removing pollutants, odors, and particles from the air and surfaces in your home. This added layer of protection can make a noticeable difference in homes affected by wildfire smoke. Schedule Professional Duct Cleaning If smoke has entered your home, particles can settle inside your ductwork. Duct cleaning removes built-up contaminants and prevents them from being recirculated, helping restore cleaner air throughout your home. Keep Up with HVAC Tune-Ups Regular HVAC tune-ups ensure your system is running efficiently and filtering air properly. During wildfire season, a well-maintained system is critical for maintaining healthy indoor air quality. Long-Term Protection for Homes in Bozeman, Belgrade & Four Corners Wildfire smoke isn’t just a temporary inconvenience—it’s an ongoing challenge for homeowners in Southwest Montana. Investing in indoor air quality solutions through your HVAC system provides long-term protection for your home and your family. By combining: High-efficiency filtration Whole-home air purification Air scrubbers Clean ductwork Routine system maintenance …you can significantly reduce the impact of wildfire smoke indoors. Breathe Easier with the Right HVAC Support Your home should be a place where you can escape poor outdoor air—not bring it inside. With the right HVAC upgrades and maintenance, you can take control of your indoor air quality in Bozeman, Belgrade, and Four Corners, even during the peak of wildfire season. If you’re noticing smoke lingering in your home or want to prepare ahead of time, working with a trusted HVAC professional can help you choose the best solutions for cleaner, healthier air. Cleaner indoor air starts with the right system—and the right team behind it.
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