Written by Industrial Stores Staff 04/24/23
For more information, please visit our website.
A few years ago, you would only find scroll compressors in special applications, including hospitals, vacuum pumps, and car superchargers. Scroll compressors are much more common today, so the big question is how to choose the perfect scroll compressor for your needs.
Although they’re now more common, scroll compressors still have niche applications. Before buying one, you need to have a clear picture of what you expect it to do and what features it needs to have.
The easiest way to do this is to answer these questions:
Whether you’re a technician, contractor, or building manager, this guide on choosing the best scroll compressor is for you.
Scroll or spiral compressors are a type of positive-displacement compressor, which means they trap fluid in a fixed volume and force it to move through mechanical means.
They use two spiral elements that trap fluid between them and compress it. One of these elements is fixed, while the second one orbits within the vanes of the fixed element.
You can see this scroll-like element in the Copeland Digital Scroll Compressor below.
The only moving parts in the compressor are the rotary scroll and motor. Emerson, the manufacturer of Copeland scroll compressors, estimates that it has 70% fewer moving parts compared to conventional models.
With so few moving parts, scroll compressors are much more reliable and quiet compared to reciprocating models. Scroll compressors can also run without lubrication, which reduces the chances of contaminating air or refrigerant with water or oil.
These benefits, paired with their small size, make scroll compressors perfect for sensitive applications. Common uses of scroll compressors include air conditioning, automobile superchargers, food and fruit refrigeration, vacuum pumps, and marine containers.
Scroll compressors use an orbital motion to compress crescent-shaped pockets of fluid caught between the vanes of the two scrolls.
Watch this outstanding video by Thomas Schwenke to see how this happens.
Due to the way they operate, scroll compressors don’t need a suction valve (although they usually have a special one-way discharge valve). Their design is simple but powerful, giving them a highly efficient compression process.
You will get smooth, reliable, and efficient compression with a scroll compressor. Learn more and explore various brands as you check out the latest prices.
CHECK LATEST PRICE
The most important factor when choosing a scroll compressor is the type of work for which you need it. There are several reasons why this is necessary:
Scroll compressors are usually single-speed. That means they only operate at full capacity, but you can also buy units with variable capacity such as this Copeland Scroll Tandem Compressor.
If you’re replacing an air conditioner compressor, consider installing a model with variable capacity. These allow exceptional temperature and humidity, typically within +/- 0.5 °F. This ensures more comfort in homes and minimal food spoilage in refrigeration systems.
When replacing an existing unit, look for a unit with the same technical specifications.
The second most important factor is your air consumption. You need to determine the total airflow you need to power all your tools and equipment.
Check manufacturer specifications and pressure requirements for all your pneumatic tools/machinery. Your scroll compressor should be able to handle the highest PSI required for your equipment during peak operation.
For the airflow in cubic feet per minute (CFM), add up all the CFM requirements for all equipment that you will be running simultaneously. Add a 30% safety margin, and you will have a minimum CFM value for your scroll compressor.
If you’re buying a compressor for air conditioning, look for manufacturer guidelines on what compressor capacity to buy.
Scroll compressors come with a motor already mounted, so you don’t need to calculate horsepower figures. For example, the Danfoss H-Series Scroll Compressor below comes as a complete package with an internal motor and terminal box.
However, you need to figure out power supply requirements including voltage, current, circuit safety, and control features. Check manufacturer guidelines for these details and be careful to follow them to the letter, as scroll compressors can be sensitive to bad connections.
In fact, some of the most common causes of compressor failure include poor electrical connections and motor problems caused by electrical problems.
Scroll compressors have a big advantage because they can operate for extended periods without excessive wear. The best models only require a few minutes of downtime for an hour of continuous operation.
If you need a continuous supply of compressed air/refrigerant, make sure that the scroll compressor you choose has the right duty cycle. For example, the Danfoss 121L Scroll Compressor below can handle 12 start/stop cycles and requires a 3-minute time-out per hour.
Turning a compressor on requires a large current draw from the mains and can cause increased equipment wear. If you have too many start/stop cycles, at some point it becomes more economical to run the unit continuously and eliminate the start/stop operations.
The rule of thumb is that you have to start and stop a compressor more than eight times an hour, consider installing a receiver tank or run it continuously.
Expert Tip: The compressor you choose must always be oversized for your particular applications. Better still, install a tank for your compressor so it doesn’t have to run all the time.
Scroll compressors are so quiet that you can install them close to the point of use. However, there are other installation considerations to think about.
The most obvious one is the electricity supply. Larger units often require three-phase power, while small ones operate off single-phase mains. Heat is also a major factor because scroll compressors generate a lot of heat and require some form of cooling.
Therefore, it’s worth taking the time to pick a scroll compressor that will run off the electrical supply you have. Also, check the space where you will be installing the unit. It needs to have good air circulation for cooling, and some manufacturers even recommend placing it near a fan or window for better cooling.
You should also think about what control system you need. For example, an automatic start/stop system based on air pressure levels will be necessary if you have a receiver tank.
Expert Tip: If you have to start and stop the compressor more than eight times an hour, it’s more economical to run the unit continuously to reduce the high current drawn at starting.
You can get a good single-speed scroll compressor for just under $800, while premium variable-speed models with sophisticated controls can reach $5,000 or more.
If you are looking for more details, kindly visit Leling.
Apart from this, the prices of scroll compressors vary only slightly from brand to brand depending on performance factors such as flow and pressure.
The table below shows the average prices of four scroll compressor models we have at Industrial Stores.
Swipe left to see moreCHECK LATEST PRICES
Our happy customers love our friendly service, fast shipping, and comprehensive inventory.
Some of the compliments and positive reviews that come up most include:
"Thank you so much for your hard work and concern, really appreciated."
— Luis S. Valverde, Thermo Air Inc., Hollywood, Florida
"I couldn't be happier to have saved hundreds of dollars."
— Ruben Marquez, Madison, WI
"I have the part, it was here early AM - THANKS SO MUCH."
— Teresa Browder, Oak Farms Dairy, Houston, Texas
The size of air compressor you need will depend on your airflow needs in cubic feet per minute (CFM), as well as the pressure ratings of your equipment. This information will be available for each piece of pneumatic equipment you are using in their user guide.
Sum up all the CFM flow requirements for all the equipment you will be operating simultaneously and add a 20 – 30% margin. Remember to use the higher CFM and PSI values for your equipment to make sure you can meet peak demand.
Scroll compressors are quieter, more efficient, and provide more consistent airflow than other types of compressors. However, this doesn’t mean they are the best since they also have a few shortcomings.
Each type of compressor has applications to which it is best suited depending on its features. The table below shows some important features of the four main types of compressors.
Swipe left to see moreDue to their design and working principle, scroll compressors are usually small in size. They tend to have leakages between the vanes of their scrolls, and larger units leak more and lose efficiency.
Also, large displacement scroll compressors require massive scroll elements, making them impractical.
Scroll compressors can be lubricated or oilless. They come in different designs, with somewhere the scrolls do not actually touch. This eliminates the need for flooding the compressor with oil or lubricant, providing clean air.
However, there are also lubricated and even oil-flooded scroll compressors, especially those that require a high compression ratio.
The way scroll compressors work is simply genius. The interlocking vanes can compress fluid with almost 100% efficiency and very little noise. Plus, they have very few moving parts and are extremely reliable and long-lasting.
That being said, scroll compressors have limited flow and pressure output. They are great for niche applications where clean air or refrigerant is required such as air conditioning, food processing, and medical laboratories, among others.
If you’re looking to buy a scroll compressor, you need to make sure that the one you choose will supply enough airflow at the right pressure for all your equipment. It also needs to meet your installation and performance needs.
Here at Industrial Stores, our expert staff are well-equipped to help you find the best scroll compressor for your needs. We will also source the right unit for you, get you reduced prices, and deliver the unit to you quickly and safely.
Shop for scroll compressors at Industrial Stores today to discover the best prices.
CHECK LATEST PRICE
Share on Facebook:
Although the idea for a scroll compressor has been around for over 100 years, the technology is only about 50 years old. As the industry continues to advance, so does the need for reliable, clean, and oil-free compressed air. Scroll compressors are ideal in commercial applications that include: medical, pharmaceutical, food, laboratory, textile, electronics, and production facilities.
Anywhere quiet, clean air is required, a heavy-duty scroll compressor is the only way to go. They come in a wide variety of sizes, up to 40 HP, and can produce as much as 116 CFM! Scroll compressors utilize a very innovative (spiral) design that compresses air quietly with fewer moving parts and less required maintenance.
Scroll air compressors use two spiral-shaped scroll pieces to compress air. One scroll is stationary, meaning it's fixed in place and doesn't move, and the other fits inside the stationary scroll and is moved in a tight circular motion without rotating. The moving scroll presses against the inside of the stationary scroll in such a way that, as it moves in a circular motion, it pushes and traps air into small pockets between the two.
The pockets of air continue being moved through the spiral toward the center. As the air moves further toward the center of the spirals, the air pockets become smaller, and the air in those pockets gets compressed.
Once the compressed air pockets reach the center, they're released into a discharge pipe to be used, or they're released into an air treatment system. An air treatment system is not included with the scroll compressor, as it's typically custom-created with the necessary components to serve the user's desired purpose.
The air treatment system utilizes air delivery piping to deliver the compressed air from the compressor, through a series of filters and dryers, into a receiver tank where the air can be held until it's used. However, some applications that make constant use of the compressed air to run assembly-line machinery may not require a tank.
A major key benefit of scroll compressors is that they're 100% oil-free. For tasks or work environments that require 100% oil-free compressed air, scroll compressors can offer that. The two spirals found in scroll compressors that compress the air don't touch, meaning there's no need to use any oil for lubrication. But this doesn't just mean oil-free air, it also means there are no oil changes.
That leads to the next major benefit of scroll compressors—they're very low maintenance. Because there's no oil to change, and there are no spark plugs to worry about, the only real maintenance these machines require is a filter change. This not only saves you time, but it also saves you money. You don't have to worry about changing out oil filters, and you won't experience the costly pressure drop across oil filters.
And speaking of saving money, scroll air compressors are incredibly energy efficient. In addition to the innovative scroll technology and lack of oil filters previously mentioned, these machines are also available with an optional built-in dryer that significantly reduces downstream pressure drop.
And if you're using your scroll air compressor for heavy-duty applications, there's an optional air-cooled IP55 class F motor designed specifically for the tough jobs. Furthermore, they're typically designed for easy serviceability, saving your more time and labor costs. So even if you weren't in need of an oil-free air compressor, the efficiency alone may be worth opting for a scroll compressor.
Last, but not least, it's important to point out that these machines are extremely quiet during operation. The fact that there's no friction between the parts reduces noise significantly, as does the fact that there are no reciprocating pistons - keeping motion more smooth and balanced to reduce vibration.
When choosing a scroll compressor, first determine which type of electrical service you have, either single or 3-phase power. Single-phase is the standard type of service, while 3-phase power is a special commercial power service. If you have access to 3-phase power, you can benefit greatly from the high-efficiency premium motors that are available in those models.
Next, consider the varying specs. How much pressure do you need? Scroll compressors generally come in 116 PSI or 145 PSI, and both single-phase models and three-phase models come available in either one. Cubic feet per minute (CFM) is another spec you should consider when selecting a scroll compressor.
CFM is the amount of high-pressure air being released per minute. This is how much work your compressor can do per minute given a set PSI. So, a 116 PSI unit that puts out 55.1 CFM will be capable of completing tasks faster than a 116 PSI unit that puts out 8.9 CFM. Don't forget the optional built-in dryer for reducing pressure drop.
If you'll be using your new scroll air compressor for heavy-duty operation, you can also consider the optional air-cooled IP55 class F motor, which is totally enclosed and highly efficient.
For more scroll compressor suppliersinformation, please contact us. We will provide professional answers.