The air conditioner in your Garland, TX home has two primary components: its indoor air handling unit and its outdoor condenser/compressor unit. If refrigerant is the lifeblood of your cooling system, the compressor is its heart. AC compressors pressurize and pump refrigerant from end to end to power heat transfer, extract humidity, and keep building interiors cool. To help you give your air conditioner the care it deserves, the following is everything you need to know about its compressor.

What Is an AC Compressor and How Does It Work?

At start-up, the refrigerant in your air conditioner is an ice-cold liquid. It travels into the indoor air handler and enters the evaporator coil. Here, it absorbs the heat from warm indoor air as it passes over. With heat added, liquid refrigerant becomes a hot, high-pressure gas. It’s routed to the outdoor condenser unit where it expels its heat and then, as needed, starts the cooling process over again.

Just as its name implies, the compressor drives this process by compressing or pressurizing refrigerant and then depressurizing or decompressing it as needed. Heat leaves refrigerant in the condenser unit as the compressor’s blower fan subjects it to ambient air.

Outdoor compressors are connected to indoor air handlers via copper refrigerant tubing. Copper refrigerant lines are durable enough to handle AC refrigerant whether it’s piping-hot or ice-cold. They can also withstand the ongoing pressure changes that compressors facilitate. In this respect, copper refrigerant lines are essentially the arteries of residential cooling systems.

Your AC Compressor’s Role In Powering Your Cooling System

Your air conditioner is hardwired into your home’s electrical system. Unfortunately, the electricity demands of air conditioners regularly exceed the available power supply. Your electrical system cannot provide sufficient electricity to start your air conditioner up or keep it running through an entire cooling cycle.

To compensate for this deficiency, AC compressors have start-and-run capacitors installed. These components harness and store energy to give air conditioners the boost they need to run and stay running until homes are cool. Start capacitors harness and hold energy for start-up and run capacitors do the same for cooling cycles. However, many modern ACs have compressors with dual capacitors that do both jobs.

AC Compressors Have Built-In Fail-Safe Measures

AC compressors have built-in fail-safe measures. Highly pressurized and hardwired, these components can cause permanent equipment damage when malfunctioning. Higher-than-normal operating temperatures can lead to blower motor failure as can unchecked refrigerant leaks. To prevent progressive problems from spiraling out of control, these units will turn themselves off before their operating temperatures or pressure levels climb too high.

AC Compressors and Manufacturer Warranties

Your air conditioner’s compressor is easily its most costly component. The value and importance of compressors are apparent in how AC manufacturers structure their product warranties. For instance, air conditioners typically come with five to 10-year limited parts warranties and separate compressor warranties that last 10 to 12 years or longer. Depending upon the age and condition of your AC, if its compressor fails after your manufacturer’s warranty has ended, it’s probably more cost-effective to replace your air conditioner rather than its compressor alone.

Another important thing to note about AC compressors and manufacturer warranties is that do-it-yourself (DIY) repairs and insufficient maintenance can result in the automatic voiding of all relevant warranty protections. Whether you suspect a refrigerant leak or problems with your blower motor, it’s best to have the issue diagnosed and resolved by a licensed HVAC company.

Common Compressor Problems and How They Affect AC Performance

AC condenser/compressor units are highly pressurized. This pressurization makes them both heavy and highly dependent upon the stability of their supporting concrete or composite pads. Whether due to shifting soil and erosion, excess moisture, or climate-related wear, changes in the integrity of this pad can negatively impact both your compressor’s performance and its lifespan. If you notice shifting, tilting, cracking, or other problems at the pad beneath your outdoor unit, you should schedule AC repair service right away.

Among the most common AC compressor problems are overheating, dirty condenser coils, capacitor failure, electrical failure, and refrigerant loss. Given the high cost of replacing compressors, you need to catch and correct these issues early on.


AC condenser/compressor units are typically installed in back or side yards. When choosing installation areas, HVAC technicians target spaces that have fixed sources of shade. This is why side yards are preferred over backyards in most cases as side yards give these units natural shade from building structures. If your condenser is exposed to constant and direct sunlight on hot summer days, this exposure alone could cause your compressor to overheat.

Airflow obstructions are another common cause of overheating. At the compressor unit, overheating might be the result of blocked condenser housing, a dirty condenser coil, insufficient insulation, or low refrigerant. Your outdoor condenser unit should always have at least 24 inches of clearance on all sides to prevent overheating. To maintain this clearance, inspect your condenser once each month. Be sure to remove all overgrown grass, weeds, shrubs, and tree foliage along with all loose, windblown debris.

Dirty Condenser Coils

When AC condenser coils are coated in grime, hot refrigerant has a hard time releasing its heat. Not only does this affect cooling in the building interior, but it also subjects compressors to undue stress. Scheduling regular, pre-season AC tune-up services to have your condenser coils cleaned will prevent overheating and premature compressor failure.

Capacitor Failure

Run, start, and dual capacitors have finite lifespans. These components can last five to 20 years depending on their quality and operating conditions. If your compressor is making loud humming sounds or if your AC is pushing warm air out of your vents, it may be time to have a new capacitor installed.

Electrical Problems

Unprotected power surges can shorten your AC compressor’s life. Power surges occur whenever there are disruptions in your utility company’s power supply. Each time power is restored, higher-than-normal voltage enters your electrical system. These surges in voltage can wear down electrical contacts and connections and leave you with a faulty or non-functioning compressor.

Refrigerant Leaks

Unchecked AC refrigerant leaks cause serious problems for compressors. When compressors pressurize the remaining refrigerant, refrigerant loss increases. Not only can an unchecked leak lead to early compressor failure, but if you continue using your air conditioner, it could also cause your compressor to collapse.

How to Safely Troubleshoot Compressor Issues

The first and most important step in safely and successfully troubleshooting any AC component is understanding the difference between fixing and troubleshooting. Troubleshooting is anything that you do to optimize operating conditions. For compressors, it includes removing airflow obstructions and resetting tripped circuit breakers. Any measures that require you to open equipment housing and tamper with moving parts could void your manufacturer’s warranty and lead to physical harm.

We help homeowners in Garland, TX get the most from their heating and cooling equipment. We offer top-notch heating, cooling, plumbing, and indoor air quality services. If you need AC maintenance, installation, or repairs, give On Time Experts a call now!

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