How to refill the CO2 Tank With an Air Compressor?

Fill up tires, run pneumatic tools or refill CO2 tanks. Air compressors are capable of doing it all. Using compressed air, air compressors can make various tasks much easier for you. The question at hand is: How to refill a C02 tank with an air compressor? Well, this is not a difficult task at all. In this article, we will guide you about this process to help make things easier for you. Let’s go!

Refilling the CO2 Tank With an Air Compressor

A C02 tank is a very useful thing to own but when it comes to carrying it to the shop in order to refill it, things can get very annoying. Not only is it very difficult to carry around, but this task can also be a little heavy on your pocket. That is where an air compressor comes in. If you own an air compressor, it can help make things so much easier.

Investing in an air compressor will not only cut down on the cost and effort required to refill your CO2 tank but will also help make the whole process much more efficient. Now you don’t have to worry about running out of gas while you are completing your job.

Steps for refilling your CO2 tank using an Air Compressor

Let us know explain the whole process in simple steps so that you can understand it better.

1. Check the integrity of the CO2 tank

Checking the integrity of a tank means checking when it was last hydro-tested. You need to get your tank hydro-tested every 5 years if you’re living in the US. After each hydro-test, the date is printed onto the cylinder so you can keep track of it.

This date is printed in the format MMCYY where the first two digits represent the month and the last two digits represent the year of the hydro-testing. Make sure that the CO2 tank you are using has been hydro-tested within the last 5 years. If not, make sure you get it hydro-tested before using it again.

2. Check tank PSI rating

All CO2 tanks come with a pre-define PSI rating that determines how much pressure is required for filling them completely. This rating is printed on the tank. The initials of the regulatory authority that has defined this rating are also printed on the tank.

Make sure that you do not fill the tank over its capacity. Be careful and try to fill the tank to around 90% of its capacity in order to prevent any accident. You can only fill it up completely if you are sure that the air that you are using is completely oil-free and dry.

3. Fill adaptor

Compressed air tanks and CO2 tanks have varying fittings that help prevent the mixing of the two. If you want to fill a CO2 tank using an air compressor, you will have to use an adaptor. Find the right adaptor because the threading on the C02 tank can be unique.

This threading can be either CGA 347 or CGA 320. Check which kind of threading your CO2 tank has and get an adaptor accordingly.

4. Empty the tank

Before you begin filling up the tank, make sure you completely empty it first. To do this, you have to connect the adaptor to the C02 tank and then attach it with the air compressor’s hose fitting without attaching the air compressor. Open the valve on the tank to let any remaining air escape. Once all the air has escaped, close the valve.

5. Fill up the CO2 tank

Multiply the tank size by two in order to calculate how much time it will take to fill it up completely. For example, if you’re using an 8-ounce CO2 tank, it will take 16 seconds to fill it using an air compressor.

Switch on the air compressor and your stopwatch at the same time. Make sure you keep an eye on your stopwatch and fill the tank very accurately. It can be very dangerous to overfill the tank so for an 8-ounce tank, it is better to switch off the air compressor at around 14 seconds.

6. Shut down the air compressor

As soon as the required time has passed, switch off the air compressor immediately. Open the bleed valve for just a few seconds in order to clear out the pipes and prevent any build-up inside. Unscrew the tank from the air compressor and you are all done.

7. Safety precautions

Following are some of the precautions that you must take in order to ensure your own safety and the safety of your tank and compressor.

  • Make sure there are no flammable objects within the vicinity of the tank or compressor.
  • Check for any punctures on the tank and compressor.
  • Make sure you properly handle the C02 tank and do not drop it because it can be very dangerous.
  • Do not use an air compressor or C02 tank while you are under the influence of drugs or medication.
  • Make sure you are wearing safety goggles.


If you own a C02 tank, it is very important to invest in a high-quality air compressor to fill up the tank. Make sure you carefully follow all the steps in this article to refill your CO2 tank using an air compressor. Let us know if you have any other queries.


1. Should You Fill Your Co2 Tank with A Compressor?

Answer: Using an air compressor to fill up a C02 tank is completely safe and very easy to do. Yes, you can even do this on your own.

2. What is Hydro-Testing?

Answer: Hydro-testing is a process that helps you check for any damage to your CO2 tank. In this, the tank is filled up with more pressure than its capacity to check if it can bear the pressure.