Compressor Types: Single, Two-Stage, Variable-Speed

July 17, 2024

Variable-speed compressors are one of the most recent products in residential air conditioning. It’s a huge leap forward for getting the perfect indoor temperature most efficiently. And if you’re wondering “What’s the difference between single-stage, two-stage, and variable-speed compressors,” here’s the simple answer: Variable-speed compressors are the better choice. 


But you weren’t looking for the simple answer, were you? Let’s talk about why it’s the better choice. 


Understanding Traditional Air Conditioning 

Single-stage compressors are the most basic type, offering only one level of operation: high. This means they run at full capacity whenever they are on, cycling on and off throughout the day. 


Single-stage compressors blast your home with cold air and turn themselves off when they reach the temperature setting on your thermostat. For example, if you set the thermostat to 75 degrees, the air conditioner will run anytime indoor temperatures hit 76 degrees. After the AC cools the house back to 75 degrees, it will turn off again. 

 

There’s also a two-stage or dual-stage compressor that provides two distinct levels of operation: high and low. This allows for more efficient and flexible cooling compared to single-stage systems. A two-stage unit runs at full capacity when you need it to and at a lower level when you don’t. Two-stage units don’t run as continuously as a variable-speed AC, but they do cycle on and off less frequently than single-stage systems. 


Basics of Variable-Speed Air Conditioning

Variable-speed compressors work differently. To maintain an indoor temperature that matches the setting on your thermostat, they operate continuously at less than 100% capacity – often as low as 25% or 30% capacity. As a result, they run for much longer cycles than single-stage AC units. In the summertime, they might run for all or most of the day! 


At this point, you’re probably thinking, “It’s hot out there! Why would I want an air conditioner that runs longer and cools my home slower?” 


Well, a variable-speed compressor’s longer run times dehumidify your home more effectively than the short cycles of a single-stage unit. One of the biggest problems with single-stage compressors is that they’re not running continuously. Relative humidity increases whenever the AC isn’t on, making you feel hotter and more uncomfortable. 


Most people deal with this problem by lowering the temperature on their thermostat, which brings us to the other benefit of variable-speed compressors: cost. 


The Cost of Comfort

A single-stage compressor blasts your home with cold air before it turns itself off. Then it turns on again when the indoor temperature increases. Most of your air conditioner’s electricity draw occurs when it turns on, not while it’s running. In the summer, a single-stage compressor turns on and off a lot, known as “short cycling.”  Short cycling can become an issue when it is above 95 degrees outside and you’re gaining heat about as fast as your A/C can remove it. 


Since single-stage compressors have short cycles, they draw a lot more electricity than a variable-speed unit that turns on and stays on (at a low speed) for hours. They also don’t dehumidify indoor air very well, forcing you to lower the temperature setting on your thermostat. As a result, the single-stage AC is much more expensive to operate! 


Two-stage compressors don’t turn on and off nearly as much. They’re more efficient than single-stage units, but not as efficient as variable-speed compressors. Variable-speed air conditioners run continuously, dehumidifying the air inside your home.  As a result, you feel comfortable at higher temperatures and don’t have to set your thermostat so low. And since they don’t turn on as often, variable-speed AC units lower your energy bill. 


 

Are There Other Benefits? 

Believe it or not, more effective cooling and greater efficiency aren’t the only benefits of a variable-speed compressor. 


If you’re concerned about indoor air quality, opting for a two-stage or variable speed unit can help purify the air circulating your home, resulting in healthier conditions for you and your family. Since they dehumidify indoor air more effectively than a single-stage unit, a more efficient system helps you eliminate mold growth in bathrooms and kitchens, prevent dust mites, and create conditions that aren’t suitable for insect intruders. 

And since variable speed units run more frequently, they also filter your indoor air more effectively. More air is cycled through your return ducts – and your air filters – resulting in a lower volume of air contaminants.  According to the American Lung Association, the average American spends 90% of their time inside, and 62% of that time inside their own home.  Having cleaner air inside your home for yourself and your family is essential. 


Nowadays, you can look beyond “keeping cool” and improve many aspects of home comfort, all through your choice of air conditioning equipment. Variable speed technology is a big reason why. 


Looking for guidance on the best air conditioner for your Lincoln area home? Whether single-stage, two-stage, or variable speed, our team can help you choose the right system. Contact Custom Cooling and Heating today to find the right fit for you. 

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Signs Your HVAC System May Be Costing You More Than You Think

September 4, 2026
When utility bills begin to rise, it is natural to blame extreme temperatures or changing energy rates. However, part of the increase may be coming from an HVAC system that uses more energy than necessary. Many homeowners searching for heating and cooling in Lincoln, NE, do not realize how much efficiency has been lost until comfort problems or unusually high bills become difficult to ignore. Aging equipment, restricted airflow, leaking ducts, and missed maintenance can all make a system work harder to heat or cool the same space.  Custom Cooling & Heating has served Lincoln and the surrounding area since 1982. Our team can help identify the less obvious problems that affect your home’s comfort and energy use. Signs Your HVAC System May Be Wasting Energy An inefficient system does not always stop working completely. It may continue running while gradually using more energy and delivering less consistent comfort. Watch for signs such as: Utility bills rising without a clear change in household use Some rooms feeling warmer or colder than others Heating or cooling cycles that seem unusually long Frequent starts and stops Weak airflow from vents New noises, odors, or excess dust A system that struggles to reach the thermostat setting These warning signs can have several possible causes, which is why a professional evaluation is often the best way to find the source. Aging Equipment May Be Losing Efficiency Heating and cooling equipment experiences wear over time. Motors, electrical components, coils, and other parts may no longer operate as efficiently as they once did. Age alone does not automatically mean a system must be replaced. A well-maintained unit may continue providing dependable service, while a newer system with unresolved problems may still waste energy. However, rising bills, frequent repairs, uneven temperatures, and declining performance can indicate that it is time to compare HVAC repair and replacement . A technician can assess the system’s condition and help determine whether a repair could restore performance or a more efficient replacement may provide better long-term value. Airflow Problems Make the System Work Harder Your HVAC system relies on steady airflow to distribute conditioned air throughout the home. When that airflow is restricted, the equipment may need to run longer to reach the temperature set on the thermostat. A dirty filter is one of the most common causes of restricted airflow. Closed or blocked vents, buildup inside the system, blower motor problems, and poorly designed ductwork may also contribute. Check filters regularly and replace them based on the filter manufacturer’s directions and your home’s needs. If airflow remains weak after these basic checks, schedule professional service rather than continuing to lower or raise the thermostat. Leaky Ductwork Can Waste Conditioned Air The furnace or air conditioner may be operating correctly while the duct system loses heated or cooled air before it reaches your living spaces. Loose connections, gaps, holes, and missing insulation can allow conditioned air to escape into an attic, crawl space, basement, or garage. According to ENERGY STAR , a typical home can lose approximately 20% to 30% of the air moving through its duct system because of leaks, holes, and poorly connected ducts. Possible signs include uneven room temperatures, excessive dust, unusually high bills, or ducts located in unconditioned spaces that become very hot or cold. Proper sealing and insulation can improve comfort and reduce unnecessary system demand. Neglected Maintenance Allows Small Problems to Grow HVAC maintenance is designed to find developing issues before they cause a breakdown or a noticeable increase in operating costs. A system may continue running with dirty coils, worn parts, drainage problems, or incorrect settings, but it may use more energy in the process. During a maintenance visit, a technician can inspect the equipment, check electrical components, clean appropriate parts, evaluate airflow, and look for signs of wear. Custom Cooling & Heating offers maintenance memberships to help homeowners stay ahead of seasonal service needs and unexpected repairs. Find the Source of Rising Energy Bills A higher bill does not always mean you need a new furnace or air conditioner. Sometimes, replacing a filter, correcting an airflow issue, repairing a component, or sealing ductwork can make a meaningful difference. In other cases, aging or unreliable equipment may make replacement the more practical option. If you need help with heating and cooling in Lincoln, NE, Custom Cooling & Heating can evaluate your system and explain the available options. Contact our team or call 402-489-9227 to schedule a service. Frequently Asked Questions Why is my HVAC bill suddenly higher? Your HVAC bill may be higher because the system is using extra energy from weather, rate changes, airflow problems, duct leaks, equipment issues, or lost efficiency. How often should HVAC maintenance be scheduled? HVAC maintenance should usually be scheduled seasonally to keep the system efficient and catch small problems early. Does an old HVAC system always need to be replaced? No, an old HVAC system does not always need replacement. Its efficiency, repair history, condition, and comfort performance should guide the decision.

How Nebraska Weather Impacts Your HVAC System Year-Round

July 2, 2026
Nebraska weather can be hard on any heating and cooling system. In Lincoln, homeowners deal with freezing winter temperatures, windy spring weather, hot summer days, and seasonal temperature swings that can put extra strain on HVAC equipment. For anyone looking for reliable HVAC in Lincoln, NE, understanding how weather affects your system can help you prevent breakdowns, improve efficiency, and keep your home comfortable all year.  At Custom Cooling and Heating , we know how quickly Nebraska conditions can affect furnaces, air conditioners, filters, and airflow. Each season creates different challenges, and staying ahead of them can help you avoid costly repairs. Winter Can Push Your Furnace to Its Limit Cold Nebraska winters often mean your furnace runs for long stretches without much of a break. When temperatures stay low, your heating system must work harder to maintain indoor comfort. That added demand can expose problems like dirty filters, worn components, ignition issues, or poor airflow. Homeowners may notice uneven heating, cold spots in certain rooms, or higher energy bills during the winter. If your furnace is older or has not been maintained, winter is often when those hidden problems show up. Scheduling heating service before peak cold weather can help your HVAC in Lincoln, NE run more efficiently and reduce the chance of an unexpected breakdown. Spring Weather Can Affect Air Quality and Airflow Spring in Nebraska often brings wind, dust, and pollen. Those conditions can affect both indoor air quality and HVAC performance. A clogged air filter or dirty ductwork can make it harder for your system to circulate clean air, especially during seasonal transitions when temperatures change quickly. If your home feels dustier than usual or allergy symptoms seem worse indoors, your HVAC system may be contributing to the problem. Replacing filters and checking airflow in the spring can help improve comfort before summer heat arrives. Summer Heat Makes Your AC Work Harder Hot summer weather in Lincoln puts major demand on air conditioning systems . During periods of high heat, your AC may run longer and more often to keep up. If your system already has issues such as dirty coils, low refrigerant, or weak airflow, summer is when they are most likely to affect performance. Some of the most common warning signs include rising utility bills, longer cooling cycles, uneven room temperatures, or an AC unit that struggles to keep the house comfortable. Preventive maintenance before summer can help identify small issues early and keep your system ready for the hottest part of the year. Fall Is the Best Time to Prepare for Heating Season Fall is one of the best times to schedule HVAC maintenance in Lincoln. After months of summer cooling and before winter heating demand begins, this is a smart time to inspect your system, replace filters, and make sure everything is working properly. A fall tune-up can help catch worn parts, thermostat problems, or airflow issues before colder temperatures arrive. It can also improve efficiency and help your furnace operate more reliably when you need it most. Nebraska Weather Affects HVAC Efficiency Year-Round Seasonal extremes are not the only issue. Nebraska’s constant shifts in temperature, humidity, and airflow can gradually wear down HVAC components over time. Motors, electrical parts, filters, and duct systems all work harder when your system is constantly adjusting to changing weather. According to the U.S. Department of Energy , routine HVAC maintenance, including changing air filters and scheduling regular inspections, helps systems operate more efficiently, improves airflow, and can extend the life of your equipment. Staying on top of maintenance is one of the best ways to prepare your heating and cooling system for Nebraska's changing seasons. That is why routine maintenance matters throughout the year. A well-maintained system is more likely to handle seasonal stress, perform efficiently, and avoid unnecessary wear. For homeowners who want to stay ahead of seasonal maintenance, Custom Cooling & Heating offers Maintenance Memberships designed to keep your system running at its best year-round. Memberships include scheduled tune-ups, system cleanings, performance and safety checks, priority service, and discounts on repairs, making it easier to prevent unexpected breakdowns before Nebraska's weather puts your HVAC system to the test. Trust Custom Cooling and Heating for HVAC in Lincoln, NE Keeping your home comfortable through Nebraska’s changing seasons starts with the right HVAC care. Custom Cooling and Heating , provides dependable HVAC in Lincoln, NE, helping homeowners stay ahead of weather-related strain on their systems. Whether you need seasonal maintenance , repairs , or a replacement , working with an experienced local team can help protect your comfort, lower energy costs, and keep your heating and cooling system running strong year-round. Contact us today and get an instant quote !