The Difference Between Oil-less and Oil-free Compressors

Businesses looking to upgrade or purchase a new industrial compressor generally find themselves asking this question: what is the real difference between oil-less and oil-free compressors? If you scour the web, you will actually find very little information that talks about the real differences between the compressors. The reason is that these compressors are often used for similar applications.

That doesn’t mean that they should be used interchangeably. Often, one compressor will work better for your particular application. To help you distinguish which compressor is right for you, let’s talk about the differences between these two compressor types.

Oil-free Compressors at a Glance

Oil-free compressors house no oil located within the compression chamber of the system. This is how the likelihood of air purity contamination is reduced.

Oil-free compressors tend to have a lower maintenance requirement as they do not need regular oil changes, but you should consider having an expert maintain the compressor system on a regular basis to ensure a full lifespan. Speaking of lifespan, due to their lack of oil, parts within an oil-free compressor tend to go through more wear and tear, so the overall compressor tends to last less time than their oiled counterparts. 

NFPA99 Medical Air Compressors

Medical Air Packages are air compressors specifically used to provide breathing air for patients and mixing air for anesthesia. These units are often oil-free systems and meet the required standards set forth by the NFPA99, National Fire Protection Association. These compressors are designed so that in the event of failure to any part of the system, there are components that can automatically take over to keep the system operating smoothly.

These medical-grade compressors are integral in helping healthcare facilities meet patient needs.

Oil-less Compressors at a Glance

Oil-less compressors have no oil present in the compressor package.

Oil-less compressors still greatly decrease the risk of contamination which is why they are often confused with oil-free compressors. Oil-less compressors work by first expelling air, filtering the air to eliminate contamination, pressurizing air, and finally cooling air for use.

Oil-less compressors are often used for similar applications to what oil-free compressors are used for, such as food and beverage production. However, oil-less compressors and oil-free compressors do offer slightly different benefits.

Which Type of Compressor is Better for Me?

Oil-less compressors and oil-free compressors are used when certain air quality is required by the ISO (International Organization for Standardization).

We’ve broken down what makes each compressor type different, but as we mentioned it really comes down to the overall use-case. If you’re looking for an opinion on which is truly better, you’ll also have to look at multiple other factors like industry codes and standards, the application needs you have, job requirements, and more.

When it comes to lifespan, the machine will always give back the amount of maintenance you put in. We recommend that you consistently service both types to ensure they are operating at peak performance. Our in-house team can provide on-demand repairs and regularly scheduled maintenance on both compressor types to ensure you do not have any unforeseen equipment issues.

If you are unsure of which compressor fits your application use best, we advise that you seek out a specialist. If you wish to speak to our specialists, you can contact us by email or phone.


JHFOSTER sells and services oil-free and oil-less air compressors from renowned manufacturers including Gardner Denver, Kobelco, Powerex, Quincy, Thomas, and more. 

If you’re looking to purchase a compressor, service your existing compressor fleet, or need some expert advice on applications and benefits, look no further, contact one of our specialists at JHFOSTER.