Fill A Compressed Air Tank

An air gauge is used to measure pressure when filling compressed air tanks.

Compressed air is used for many purposes, ranging from inflating tires on automobiles and motorcycles to operating pneumatic tools and equipment. Portable air tanks fill a demand for compressed air when an air compressor is not available for use or not practical for logistical reasons. Filling a compressed air tank is a task the tank owner can accomplish with the use of an air compressor. A personally owned air compressor or air available at service stations and an air pressure gauge are all that is required.


1. Check the maximum pressure rating of the air tank. The rated pressure is indicated in pounds per square inch (psi). If there is no indication of limit on the tank, do not use it.

2. Drain any accumulated moisture from the compressed air tank before filling. If the tank has no drain valve, you may skip this step.

3. Remove the cap from the fill valve. The valve is the same size and type as used on automobile tires. The location of the valve differs depending on manufacturer.

4. Attach the fitting of the air supply hose to the valve stem of the air tank and depress the fitting firmly. If the air tank has its own pressure gauge installed, keep a close watch to avoid over-pressurizing. Wear safety glasses when filling the air tank.

5. Stop filling the air tank periodically and check the tank pressure using an air pressure gauge if the tank does not have one installed. As the air pressure in the tank increases, check more frequently until the maximum amount is reached.

6. Remove the air supply fitting and replace cap.