Which compressor for scuba tank ?
How to fill a scuba tank?
There are several ways to fill a scuba tank. For a mini scuba tank you can fill them in 3 different ways:
- With a high pressure hand pump
- With a filling station, by transferring the air from a larger dive tank
- With a diving compressor
Each of these filling methods has different characteristics and has the capacity to fill larger or smaller cylinders.
For the hand pump, the maximum cylinder size is 0.5 L. For a filling station, the size will be 0.8 L.
For a diving compressor this will depend on the power of the compressor, which we will study in the next paragraph.
What power for my scuba compressor?
The power of the compressor will depend on its power supply and its size. There are three types of compressors:
- The 12 V mini compressors, which are powered by a battery. These have a power of less than 300 W, and are capable of filling cylinders up to 0.8 L
- The 220 V mini compressors, which are powered directly from the mains. They have a nominal power of about 2000 W but require a much higher power to start up (over 10 kW)
- Standard dive compressors which are capable of filling any size of dive tank. They are most often found in scuba diving centers or clubs. It is more rare to find them in private homes because of their size and high price.
The difference between mini compressors and standard compressors lies in their ability to be fixed or mobile. This characteristic will be developed in paragraph 4.
Manual pump to fill my tank, or electric compressor?
The choice between a manual pump or a compressor will naturally depend on the size of the dive tank.
If your tank has a volume of 0.5 L or less, you can fill it with a manual pump in about 15 minutes.
If the cylinder has a volume of more than 0.5 L, you will have to turn to an electric compressor, which will allow you to fill larger cylinders.
You can also choose the electric compressor to fill your 0.5 L bottle in order to save time (3 minutes of filling against 15 minutes for the pump) or to do it without forcing.
Fixed or mobile compressor?
As for the choice between the manual pump and the electric compressor, the choice between fixed and mobile compressor will be made according to the size of the diving cylinder.
If you have or wish to purchase a tank with a volume of 0.8 L or less, you can choose a 12 V compressor, which can be taken anywhere and will fill the tank in about 20 minutes.
If your tank has a volume of 2 L or less, you can have a 220 V compressor, which will guarantee a filling in less than 12 minutes, while giving you the possibility to move it if needed.
If you want to fill a larger scuba tank, you will have to choose a fixed standard scuba compressor.
There is always the option of using a smaller capacity compressor to fill a larger tank, but you will need to allow for breaks in order to let the unit cool down.
These breaks will also allow you to change the filters in order to maintain good air quality in the tank.
How much does a scuba compressor cost?
To buy a scuba compressor, you will have to turn to a manufacturer / reseller of diving equipment.
On MiniDive website, you can order a scuba tank compressor pack for a price ranging from 849€ to 2699€.
The good compromise to go several meters deep to explore the sea bed and be autonomous in terms of filling will be to choose for example the pack including the 0.8 L aluminum bottle and the 220 V compressor. This will allow you to stay underwater for up to 15 minutes and to fill the bottle in less than 4 minutes with the compressor connected to the mains (220 V for Europe and 110 V for the USA).