How does an air compressor work? A compressor builds up the air inside its chamber (storage tank), and, when full, it shuts down and stores the air inside ready for use.
During use, the air inside the tank reduces, and the compressor then re-pressurizes itself to ensure a constant supply of compressed air.
Air compressors have a wide range of applications, and they are used in different places. From gas stations to large industrial plants, they work by converting power into compressed air.
Air compressors differ from a pump because they work pressurizing gas or air while pumps work exclusively with liquids.
General Air Compressor Info
To further answer the question of how does an air compressor work, let’s discuss two important factors:
- The method of air compression and
- The pressure they deliver
Most Popular Types of Air Compressors: Compression Methods
When looking methods of compression, we have 2 main types of air compressors: positive displacement compressors and dynamic displacement air compressors.
Each of these types of air compressors can be divided into 3 different level of pressure. Make sure to check your air tools or paint sprayer for the amount of PSI you will need to work continuously.
Most paint sprayers don’t require a ton of air to operate, usually less than 50 PSI, but brad nailers require considerably more air to work without delays. It’s a bummer to have to wait for your compressor to catch up to your air tools so make sure you grab the right size for your tools.
- Low-pressure types (150 psi or less)
- Medium-pressure models (150-1,000 psi) and
- High-pressure types (over 1,000 psi)
Positive Displacement Compressors
These are your most common types of compressors. They force air inside their chambers until maximum pressure is achieved inside the tank. From there, the air is then discharged through outlet valves based on the settings you’ve put in place.
There are three main types of positive displacement compressors, and they include:
- Rotary screw compressors that use helical screws for guiding air into the tanks where the volume is lowered as the air builds up inside
- Piston compressors, which use pistons and one-way valves to push air into the chambers and compress it
- Vane compressors that utilize a slotted rotor to channel the air into the chamber and compress it
Dynamic Displacement Compressors
These feature centrifugal and axial compressors. A rotating device within the compressor imparts kinetic energy onto the air being sucked in, and this energy is what’s usually converted into the expended pressure energy.
These spinning impellers can accelerate or decelerate the air in the compressor to increase its pressure or lower it.
How Do Portable Air Compressors Work?
How does a portable air compressor work? The best way to learn this is to read your user manual carefully before you start operating the device. However, for portable air compressors, I find it's easy and straightforward to operate them.
- Start by checking that everything is in peak condition. By everything, I mean the oil and fuel levels, battery level, hoses are in good shape, attachments are on tight etc.
- Close all the air outlet valves and turn on your compressor by pressing the start button.
- Give your device some time to warm up, and, once it does, proceed with your work
- When shutting it down, start by closing all the outlets and give it time to run for several minutes, as it reduces its engine speed and cools down. Once it cools, you can press the stop button.
Most portable air compressors have a single-stage piston design. This makes them lighter in weight and easier to carry. The piston forces air through the inlet valves, compresses it, and then discharges it through the outlet valve.
They also require less maintenance because they are made with less moving parts. Perfect for DIYers to use at home.
How Does an air Compressor Regulator Work?
A regulator is a valve that ensures there is constant pressure being supplied to any type of fluid. Every air compressor has a regulator within its system.
This component works by stabilizing the air supply being delivered through the outlet no matter what the air pressure may be on the inlet side. It restricts the flow of air based on the settings you put in place.
Regulators use springs that move up or down, this, controlling the area left for air to pass through — a sensor, known as a diaphragm, shifts as the pressure changes.
It is important to ensure a smooth transition between the air pressure changes. Switching instantly to very high or very low pressure can damage your regulator and compressor.
When you turn on an air compressor, it runs until your pre-set air pressure setting is reached. From there, the regulator ensures this pressure is maintained during use by providing the right amount of air pressure that is needed for your job.
How an Air Compressor Works: See it on YouTube
Below is an example of a well-documented video that will help you have a better understanding of how these machines perform their tasks.
How Does a Small Air Compressor Work?
Small air compressors basically use the same principles outlined in the processes above. The only difference between them and bigger compressors is that they use fewer pistons. Most of them operate on 1-stage piston pumps, and because of this the power and PSI output is not as much as the bigger compressors.
How do Air Compressor Pressure Switches Work?
For you to fully understand how an air compressor works, let’s look at the mechanics of air compressor pressure switches.
When you are using your compressor, the pressure inside it is bound to reduce because of the decreasing air level, and this could affect the performance of your work. However, that doesn’t happen, does it? All that is thanks to the pressure switch.
Let me explain how.
The switch reacts to the changes in pressure within the device. It is connected to both the power supply and the motor. As the pressure reduces, it gets to what is called the cut-in pressure setting of the switch.
Once that point is reached, the switch lets power through it, which is transferred to the motor. The motor gets turned on, and a fresh supply of compressed air is driven into the storage tank. This brings the pressure level back up inside your tank, ensuring you have a steady supply of air at a steady PSI output for your job.
I hope I have answered all your questions about how does an air compressor work. The overall concept is that they take in air, compress it, and then control how it’s let out.
Of course, there are other processes involved, such as pressure control using regulators and pressure switches, but, all in all, the above processes are the basics of how an air compressor works.