Introduction
Do you think your AC compressor has stopped working? Are you even sure what an AC compressor is? If you’re not, that is okay. In this blog post, we’ll discuss what an AC compressor is, common problems with it, how to fix it, what to do if you can’t fix it and more. We hope this blog post answers any of your questions you may have. If not, feel free to leave a comment below, and we’ll do our best to help and point you in the right direction.
What Is an HVAC AC Compressor?
An AC compressor is a vital piece of equipment in your air conditioner that compresses refrigerant and circulates it through your system. It compresses refrigerant by decreasing the volume of what it is in to increase its pressure. By increasing the refrigerant pressure, it compresses it.
What Is Refrigerant and What Does It Have to Do With an AC Compressor?
Refrigerant is a set of chemicals that are vital to the cooling process. If the AC compressor is the heart of your air conditioner (AC), then the refrigerant is the blood. During the cooling cycle, refrigerant transitions from a gas to a liquid and back several times.
Types of Refrigerant
There are several types of refrigerants, depending on the type of air conditioner. The most common refrigerants are Chlorofluorocarbons (CFCs), Hydrochlorofluorocarbons (HCFCs), and Hydrofluorocarbons (HFCs). Chlorofluorocarbons are now strictly regulated due to their negative impact on the environment. Hydrochlorofluorocarbons were created to replace Chlorofluorocarbons, and Hydrofluorocarbons do not contain chlorine, unlike the others.
Some refrigerants produce greenhouse gases that can be harmful to the environment. However, more air conditioner manufacturers are opting for safer alternatives, which are not only better for the environment but also provide better air quality.
While refrigerant is an essential part of an HVAC system, without the AC compressor, the system can’t function. The AC compressor is one of the reasons why the refrigerant can change states as it compresses it.
Types of AC Compressors
Just like refrigerants, there are several types of AC compressors: reciprocating, scroll, screw, rotary, and centrifugal. According to Carrier Enterprise, the most common type of AC compressor is the reciprocating AC compressor. In simple terms, reciprocating AC compressors use pistons and cylinders to transport refrigerant. While an AC compressor may seem complex, it is because it plays such an important role in your HVAC system. Without it, your air conditioner would not be able to work.
Common Problems with HVAC AC Compressors
AC compressors rarely break when properly maintained, but it still happens. When it does, there are a few potential causes:
Too Much or Too Little Refrigerant
When there is too much or too little refrigerant in your air conditioner, your AC compressor is bound to run into trouble. As mentioned earlier, refrigerant is crucial to the cooling process.
Too Much Refrigerant
When there is too much refrigerant in the AC compressor, you may notice an increase in your utility bills, strange sounds coming from the unit, weak airflow, and your AC system randomly shutting off. This happens because excess refrigerant floods the system, causing your air conditioner to shut off.
When excess refrigerant floods the system, the AC compressor can overheat, and in an effort to save itself, shut down. Excess refrigerant only occurs in cases where someone adds too much to the system, either due to inexperience with HVAC systems or negligence on the part of an HVAC technician.
Too Little Refrigerant
On the other hand, an AC compressor with too little refrigerant is a more complex issue. Usually, when an air conditioner has low refrigerant levels, it is because it is leaking. The best thing you can do when you have a refrigerant leak is to turn off your AC unit as soon as possible and call an HVAC technician. If you can, try to locate the leak and see if there is anything you can do about it. The information will be invaluable to the HVAC technician and may save you some money in the long run, as you will stop losing refrigerant because of it.
Issues with the Coils
When there is a buildup of debris in the coils, the AC compressor runs the risk of overheating. The compressor has to work harder to expel the same amount of air due to the blockage in the coils, causing it to run longer. Some ways to fix issues with the coils include cleaning the debris around the outside unit and cleaning the coils themselves.
Once you have cleaned the coils, turn on your AC to see if it has helped. If it has, the problem was likely a buildup of debris in the coils. If it hasn’t, you can rule out dirty coils as the cause of the compressor issues. This process can help narrow down the issue, and bring you one step closer to getting your compressor back in working order. Regular maintenance can help prevent buildup of debris in the coils.
Electrical Issues
Electrical issues can cause problems with AC compressors, often stemming from damaged electrical wires. Wires in your air conditioner system can become damaged when acid builds up in the system. A common sign that an AC compressor is damaged due to electrical problems is if it randomly shuts off. The best way to prevent electrical damage, along with other AC compressor issues, is through routine maintenance.
Clogged Air Filters
A clogged air conditioner filter can cause several problems, including issues with the AC compressor. When a filter is clogged, airflow is restricted, and the efficiency of the air conditioner drastically decreases. As the air conditioner struggles to cool your home, it uses more power, causing your utility bills to go up.
Can You Fix It Yourself?
You don’t need to call an HVAC company to change your air filter; you can save some money and easily do it yourself! Depending on the size of the filter and other external factors, such as if you own pets or live in a dusty environment, you may need to change your filter more frequently. When in doubt, change your air filter to see if it helps your AC compressor problems.
We cover how to change your air filter in the “Change the AC Filter” section down below.
How to Fix an HVAC AC Compressor
There are several ways to fix an AC compressor, some simpler than others. Even the smallest amount of maintenance can help fix an issue. Before getting to work, you should always turn off your AC. Once you have turned it off, you can start troubleshooting. Below are a few easy ways to try and fix your AC compressor:
Flip the Circuit Breaker
Your AC compressor may have turned off due to your circuit breaker. If you have noticed that your AC has turned off or that any lights in your house are not functioning, flip your breaker. Family Handyman offers a useful guide on how to fix a tripped circuit breaker. Before flipping your breaker, turn off the lights and unplug any electrical devices. If you find flipping your circuit breaker fixes your air conditioner, it may indicate an electrical issue. If you suspect you have electrical problems, schedule an appointment with an electrician.
Change the AC Filter
A quick way to troubleshoot your AC compressor is to change the filter as mentioned above. Changing an AC air filter is a fairly simple process. If you have not changed your air filter in three months or more, it is worth doing so before contacting an HVAC technician.
How to change your AC filter:
- Turn off your air conditioner. You can do this by either flipping the circuit breaker in your electrical panel associated with your air conditioner or turning your thermostat off.
- Locate your air filter. It will most likely be in the air handler or air return duct. If you have a ductless air conditioner, then refer to this blog post, where we specifically discuss how to clean ductless system filters.
- Remove your old air filter. Depending on where it is located, you may have to unhook latches to release a drawer, remove clamps to take off the air filter cover, or remove the cover of a vent.
- If you don’t know what size filter you need to replace, look at the sides of the old filter. The size of the filter should be listed, and if it isn’t, make sure to measure it before replacing it.
- Install your new filter. On your new filter, there should be an arrow. The arrow shows which direction you should install the new filter in. Install the filter with the arrow pointing towards the air conditioner and airflow.
Clean Condenser Coils
The condenser coils in your HVAC system are located inside the outdoor unit, known as the condenser. The condenser coils positioned are directly behind the AC fins, which are pieces of metal that help expel hot air and protect the condenser coils.
How to clean your condenser coils:
There are several ways to clean condenser coils. One way to clean condenser coils is to use a dedicated condenser brush. With the dedicated brush, gently clean between the fins and remove debris from the coils.
Another way to clean condenser coils is to use a condenser coil cleaner. Condenser coil cleaners are typically foam sprays that can be rinsed away with a hose. Most are available at large retail stores.
A third way to clean the condenser coils is to use detergent and warm water. When using detergent and warm water to clean your condenser coils, check that the detergent is safe to use on them. Some detergents may not be suitable for the job. You can clean your condenser coils in various ways, but always be careful and follow the directions listed on the equipment you are using.
Call a Reliable HVAC Company
When all else fails, the best way to fix an AC compressor is to call an HVAC company. Choosing a trusted HVAC company to look into your HVAC problems can make a significant difference.
In previous blog posts, we’ve emphasized the importance of doing your research when choosing an HVAC company. Check the reviews to get an idea of the HVAC company’s response time, accessibility, and quality of work. If most reviews suggest that the HVAC company falls short in these areas—or others—consider looking elsewhere. Choosing a reliable HVAC company can help fix your AC compressor and prevent problems down the road.
What to Do When You Can’t Fix an HVAC AC Compressor
Sometimes, AC compressor failure happens no matter how much you try to troubleshoot. AC compressors can reach the end of their lifespan or become damaged beyond repair. Usually, it’s more cost-effective to replace an entire air conditioner than just an AC compressor due to their high price tag.
According to Home Advisor, the average AC compressor costs around $1,200 to replace in 2025. Not only is it expensive to replace an AC compressor, but when an AC compressor fails, it is usually not the only part damaged in the air conditioner. This can be due to the faulty compressor or the age of the unit itself. Sometimes, the most cost-effective solution is replacing the entire air conditioner and starting fresh.
Conclusion
While an AC compressor can be difficult to understand, it is a vital part of your HVAC system. Without it, your HVAC system would not be able to function. In this blog post, we covered what an AC compressor is and why it exists in your HVAC system, common problems with AC compressors and why they happen, ways to fix an AC compressor, what to do if you can’t fix your AC compressor and more. Still confused and want to ask us a question? Leave a comment below. We hope this blog post helped you out.
Do you live in Jefferson County or the surrounding areas and are experiencing AC compressor issues? Give us a call at 636-475-9384. We would be happy to take a look and offer a free estimate.