You may or may not already be aware that not all air compressors are used for all jobs! They vary in both size and of course their power level. The best way to estimate what you will need is to take a careful look at the power requirements of any of the air tools you plan on using. Then its a simple matter of choosing one that is slightly more powerful than youll need so that you have the ability to purchase an air tool that needs a bit higher power level.

An air tool you often see in a contractor’s toolkit is the rotary screw compressor. There are many options when it comes to purchasing a rotary screw compressor. If you want one that is powerful, don’t skimp on cost. A cheap air compressor is only useful for putting air in your tires.

One way compressors are rated is by horsepower (HP). Unfortunately the HP listing isn’t always the best way to estimate how much power the air compressor is going to draw. Often values of HP are inflated.

A better value to look at is the PSI. This means pounds per square inch. Most air tools need 90 PSI to function. But if the compressor has a listing of 125 to 135 PSI, it will not be able to properly run the 90 PSI air tool. This is because what the PSI is really measuring is shut off pressure, and that value does not account when there is a loss of pressure in the line. If you want to get the best efficiency from your 90 PSI tool, think about a compressor that has two-stage pressure shut off. The first stage will shut off at 90 PSI, and the second stage will wait until 175 PSI to shut off.

Next you will take into account the “cubic feet per minute” or CFM. The majority of air tools manufactured today will require 4 to 6 CFM. Not a big deal here, since at 90 PSI you will be getting 3 to 4 exact horsepower. CFM merely tells you how much air is being moved.

Another thing of import, depending on how you plan to use the compressor, it’s tank size. A regular pump and motor with the normal 30 gallon tank is just fine if what you are doing only needs you to use short bursts. But for heavy use, you’ll be much better off using a smaller tank with a significantly stronger motor and pump, of course with attentive consideration to the stored air in the tank.

This is why you’ll often see contracting professionals using multiple air tools simultaneously; they know that a 150 PSI rated compressor is a superior choice when using the compressor on a long-term, continuous basis.

Unlike portable compressors, truck mounted ones use the truck to power the compressor. The problem is that you have to keep the truck running in order for the compressor to work. For the contractor who needs to have the compressor running for a long period of time, the better choice is an affordable compressor or possibly one that is mounted on a deck. Just like truck mounted compressors, deck mounted ones are set on a truck’s bed that is removable, which makes it possible to leave the compressor on-site as opposed to having to drag it back and forth for each day of consecutive work.

Also there are both electrical and gas powered compressors. If you are likely to be on a site that lacks electricity, then the gas powered compressor is your best choice.