How to Choose the Right Air Compressor in 5 Simple Steps
Air compressors are versatile machines that perform a variety of tasks, which can serve as a headache for buyers as they navigate an unfamiliar marketplace for the first time.
Our team has compiled a quick, easy-to-follow list to help buyers clearly understand the products they are looking at before making any decisions. We have narrowed our process down to six key factors, but recommend you contact our expert team by calling 866-778-6572 or sending an email to firstname.lastname@example.org if you have additional questions.
1. Air compressor grades
Compressors come in three main grades based on capacity and applications — consumer, contractor, and commercial — though buyers should be aware of definitions for each to determine which best fits their needs.
Consumer grades are the lowest in terms of pressure, typically designed for a garage or small workshop that uses a single tool at a time. The next step up is contractor grade, which are portable and will enable use of work site tools like nail guns and roadside repair tools. The top tier of tools is commercial grade, which are known for powering several tools at once with a steady supply of compressed air.
2. Type of compressor: Single or two-stage?
Single-stage air copmressors are smaller models with a lower capacity, and can typically be moved manually. These are ideal for applications like air brushing for small shops and homes.
Two-stage compressors are best suited for garages and manufacturing facilities, able to provide enough power to simultaneously run several air tools. These models typically come with a higher price tag because they compress the air twice and have storage tanks that can reach a capacity of up to 200 gallons.
3. Capacity and delivery
The capacity of your compressor and delivery will depend on four main factors, all of which should be considered carefully to ensure they meet the requirements of a given application.
- Pound-force per square inch (PSI): The higher the PSI value, the more compressed air for a given tank size
- Cubic feet per minute (CFM): A measurement of possible air delivery, with higher values being more practical when attached to multiple tools
- Horsepower (HP): The amount of power produced. A higher horsepower produces a greater PSI value
- Tank size: A larger tank size will hold a higher PSI value over long durations
4. Rotary screw or piston compressors?
Piston air compressors are most common in the automotive service industry, and will generally supply a lower air output delivery and lower air quality. They also generate more noise and operate at higher temperatures.
Rotary screw compressors are regarded as having better reliability and air quality, in addition to fewer maintenance needs. Despite a larger upfront cost, these units will compensate for additional costs in the long run.
5. Power source of the air compressor
There are three main types of power to consider for your compressor — electric, petrol engine-driven, and diesel. Each has its own advantages based on a buyer's preferred application.
Electric air compressors are quieter and can be used in places where proper ventilation is a consideration. That said, they tend to offer less power than their fossil fuel-driven counterparts and have serious constraints in outdoor uses. Larger models need a supply transformer, meaning they are not suitable for portable applications.
A petrol engine-driven compressor is typiclaly lighter, quieter, and cheaper than a diesel model, while also providing more contorl over its engine. The caveat here is that these models cannot provide an comparable torque output to an equally-rated diesel model and come with higher running costs.
Diesel air compressors are portable, work in adverse weather conditions, and are more powerful than any other model. Their robust nature and lower fuel cost compensate for a higher upfront cost on the unit. The disadvantages typically include excess noise and toxic exhaust fumes that may make them unsuitable for certain applications.