Types Of Air Compressors
The type of air compressor that you choose to use in your compressed air system can heavily influence overall efficiency. It is important to understand the differences between the main types of air compressors before choosing one for your compressed air system.
The five main types of air compressor types are reciprocating, rotary, centrifugal, screw, and scroll. All of these different air compressor types will perform best under certain circumstances. These circumstances mainly revolve around the way you utilize your compressed air system.
This guide will provide you with all of the information that you need to better understand the differences between these five air compressor types and the specific applications where they will be best utilized.
The five main types of air compressor types are reciprocating, rotary, centrifugal, screw, and scroll. All of these compressor types have their own unique characteristics and different applications for which they would be best suited.
These characteristics will be detailed in the section below. You can use this information to better understand the different types of air compressors and the different ways that they function.
Air Compressor Types
Reciprocating Compressors
A reciprocating compressor operates by a reciprocating function involving the piston within the cylinder. The piston works to compress the refrigerant as the piston works its way down to create a vacuum. This will cause the pressure to rise above the intake valve which will force it to open and suck the refrigerant into the cylinder.
Once the piston reaches the bottom, it will begin to move upward again, causing the intake valve to close. This will trap refrigerant inside the cylinder and cause it to compress. The pressure will then begin to rise and then be expelled through the exhaust valve of the cylinder.
Reciprocating air compressors are a positive displacement type of compressor, which provides a constant flow independent of outlet pressure. They are commonly used in a home or small business setting as they are generally more compact than other types of compressors.
Reciprocating air compressors are less powerful than rotary types but can function at a lower energy consumption level. Reciprocating air compressors have been known to produce more heat and a higher noise level than other compressors, making them not an ideal choice for extended periods of use.
Rotary Compressors
A rotary compressor uses a roller to compress the refrigerant by rotating within the cylinder. As the roller rotates around the shaft, it will remain in contact with the wall of the cylinder. This process will cause the refrigerant to become compressed as the space inside the cylinder is reduced.
Once the exhaust valve becomes exposed after coming into contact with the roller, the high pressure will be released through the exhaust valve. Rotary compressors are extremely efficient as the process of taking in refrigerant and compression happen simultaneously.
Rotary air compressors are also positive displacement compressors. One of the biggest advantages of a rotary air compressor over other types is the fact that it can operate continuously with no issues. They are also the most durable of all the compressor types, with well-maintained machines lasting up to 15 years.
Rotary air compressors are the most expensive of the positive displacement types of compressors. They also generally require more routine maintenance and repairs to function properly. This can lead to a high cost of maintenance over time.
Centrifugal
A centrifugal compressor uses an impeller wheel that rotates to create centrifugal force to apply to the refrigerant. The refrigerant is sucked into the impeller wheel by a wide circular intake flowing between the impellers.
This will cause the refrigerant to become more pressurized as it is forced against the sides of the chamber. This is one of the most common ways to utilize compressed gas as there are few moving components and little room for error in the internals of the compressor.
Centrifugal air compressors are dynamic, unlike the rotary and reciprocating types. This means instead of using a closed reserve of air, they draw air in from outside of the compressor to function. They have a high horsepower threshold making them ideal for heavy-duty and demanding equipment.
They are among the more affordable air compressor types. You can however expect to incur more repair and maintenance costs if using a centrifugal air compressor in your setup.
Screw Compressors
A screw compressor uses two offset spiral disks to compress refrigerants. The disks that are located in the uppermost position will remain stationary while the bottom disk circles around continuously. This motion will cause sealed spaces to appear in the chamber.
The refrigerant will be forced into these sealed spaces and compressed until finally it is discharged through the center of the disks.
Scroll Compressors
Scroll compressors use an orbiting scroll to compress gas and refrigerants. The orbiting scroll is powered by an electric motor that rotates a shaft within the chamber. This will cause the gas to be captured between the fixed and orbiting scroll. Scroll compressors are considered the quietest and smoothest operating machines out of the five main types of compressors.
Scroll air compressors are another positive displacement type. They are known for leaving the smallest carbon footprint of all of the air compressor types. This makes them a great option for industries that hold themselves to high environmental standards.
The Cost Of Different Air Compressors
You can purchase a 5HP air compressor for anywhere between $1200 to $4200, depending on the type of compressor you purchase. You can expect to pay much more for a compressor with more HP.
With the proper maintenance, your purchase could last you up to 15 years. You should shop around different dealers to ensure that you get the best price for your air compressor.
The table below contains the average prices for each type of air compressor for the 5HP model. You can expect the price to scale appropriately when purchasing compressors with higher HP. This information can help ensure that you are paying the average price for your air compressor.
| Semi-Hermetic Compressor Type | Avg. Cost (5HP) |
| Reciprocating | $1400 |
| Rotary | $2100 |
| Centrifugal | $4200 |
| Screw | $2700 |
| Scroll | $1800 |
Air Compressor Types By Application
The uses and efficiency of the different air compressor types vary based on the job that you are undertaking. It is important to consider the different strengths of the air compressor types before you commit to adding one to your compressed air setup.
The list below will contain information regarding the common uses for the different air compressor types. This will help you decide what air compressor type is appropriate for your situation.
Reciprocating Air Compressor Uses
Reciprocating air compressors are best suited for short, flexible jobs involving hand tools that utilize compressed air. Because of the low energy consumption of reciprocating air compressor and their portability, they are ideal for these types of jobs.
You should not use a reciprocating air compressor for jobs that require extended use or for powering heavy-duty machinery.
Rotary Air Compressor Uses
A rotary air compressor is best suited for heavy-duty, prolonged use. They are typically used in construction situations to power jackhammers or sand-blasting machines. These are a much more industrialized compressor type and will often be more powerful than you need for home use.
Centrifugal Air Compressor Uses
Centrifugal air compressors are best used with heavy equipment. Centrifugal air compressors are the most powerful of all the air compressor types. This means that you can use it to power even the most heavy-duty and demanding equipment.
Screw Air Compressor Uses
Screw air compressors are also best utilized with heavy and demanding equipment. Screw air compressors are able to generate a large amount of pressure. This allows them to properly power even the most demanding machinery and tools.
Scroll Air Compressor Uses
Scroll air compressors are best utilized in environmentally conscious work areas and businesses. Because the scroll air compressor runs the cleanest of all of the air compressor types, they have become popular with companies that aim to leave a low carbon footprint.
Scroll air compressors are typically not powerful enough to power heavy-duty equipment. They are best utilized in smaller construction or home settings.
How To Choose The Right Air Compressor Type
To choose the right air compressor, you will need to consider the air quality, energy efficiency, portability factors, and your needs for the future in regard to your compressed air system. This is an important step in choosing the air compressor that is right for you.
The list below will discuss these factors in detail. You can use this information to help influence your decision when choosing an air compressor type.
Air Quality
If you aim to have clean and low emission manufacturing or working environment, then using a compressor that is oil-powered could be in opposition to those goals. There are oil-free options for all of the compressor types discussed in this guide.
An oil-free compressor will typically be more expensive than its oil-powered counterpart but will have a smaller operation cost over time. If you need to rely on an oil-powered compressor, you should consider purchasing the scroll compressor, as it has the lowest emission rating of all the compressor types.
Energy Efficiency
You should also consider the energy efficiency of the air compressor type that you are purchasing. You should consider purchasing a variable speed-driven model of the compressor type you are interested in.
Variable speed-driven compressors are known to save energy and money. This is because you can increase and decrease the output of a variable speed-driven compressor whenever you wish. This eliminates the need for a cool-down period that typical fixed-speed compressors need.
You should also consider natural gas-powered versions of the compressor type you are interested in. Since these compressors run on natural gas rather than diesel or electricity, they can operate more efficiently and are less prone to overheating.
Portability Factors
You should also consider how often you are having to move your air compressor between worksites. If you are frequently having to transport your air compressor, you will be better suited with one that is more portable.
The more portable an air compressor is, the less power it will be capable of producing. That being said, most air compressors that are small enough to be considered portable will be more than enough for smaller construction projects.
Needs For The Future
You should make sure that the air compressor type that you choose will be compatible with any additional features or components that you wish to add in the future. You should plan for any coupler or air hose splitters that you may wish to add to your compressed air system.
This means ensuring that the air compressor type you choose is compatible with the type of add-ons that you are planning for the future. There are many different components that you can add to your compressed air system to improve efficiency.
Because of this, it is important that you plan ahead when purchasing an air compressor. This will ensure that you do not wind up with incompatible parts when you begin to upgrade your system in the future.
Air Compressor Types Comparison Table
The table below contains information regarding the different air compressor types. You can use this side-by-side comparison to help make an informed purchase decision when choosing an air compressor type.
| Air Compressor Type | Cost (5HP) | Lifespan (Years) | Uses |
| Reciprocating | $1400 | 10 | Small Construction Jobs, Power Tools |
| Rotary | $2100 | 10 | Heavy-Duty Machinery, Tools |
| Centrifugal | $4200 | 15 | Heavy Machinery, Heavy-Duty Tools |
| Screw | $2700 | 10 | Heavy Duty Power Tools |
| Scroll | $1800 | 12 | Small Construction jobs, Home Use |
Final Thoughts
This guide has provided you with all of the information that you need to better understand the differences between the five main air compressor types. As this guide indicates, all of the air compressor types have specific circumstances where they will be best utilized.
This guide can help you identify the different applications where the air compressor types would be appropriate. It is important to carefully consider the different factors when making a purchase decision. This can help you avoid purchasing the wrong type of air compressor for your situation.
