Check Your Tank Before Filling

• Both HPA and CO2 tanks have a maximum capacity. To avoid overfilling the tank, check the tank's maximum capacity first. CO2 tanks fill by volume, and this measurement will be printed or stamped somewhere on the tank. Manufacturers fill HPA tanks to a specific pressure, commonly 3,000 pounds per square inch (psi) or 4,500 psi, also printed on the tank.
  
  All tanks also have a stamp or imprint with a hydrotest expiration date. For new tanks the expiration date is usually three to five years from when the tank is manufactured. Check that your tank has not expired.
  
  Always visually inspect tanks for damage before filling. Never fill a tank that shows any signs of physical damage. Also make sure the regulator is properly fitted and undamaged before filling.
  
  

Using a CO2 Fill Station

• To refill a CO2 tank, you'll need a CO2 fill station attached to a bulk tank and a scale. Attach the empty CO2 tank to be filled to the fill station. Empty the CO2 tank by slowly opening the purge valve. Do not allow the tank to drain too quickly.
  
  Weigh the empty CO2 tank and zero the scale by putting the empty tank on it and setting it to zero. Chill your tank, then open the on/off valve of the bulk tank to allow 1 to 2 ounces of CO2 into the empty tank. Open the purge valve and allow the 1 to 2 ounces to quickly flow from the tank, thereby chilling it.
  
  Open the on/off valve and, using the scale, fill your tank to 1 to 2 ounces below it's capacity. Close the bulk tank on/off. Remove your tank from the fill station and open the purge valve to allow excess CO2 in the line to escape.
  
  

Using an HPA Fill Station

• Before you use an HPA fill station, make sure your hydrotest date is current. Make sure all fittings and hoses are securely fastened and there is no visible damage. Close any bleed valves between the bulk tanks and the fill station.
  
  Slowly open the valves of the bulk tanks to charge the system. Attach the fill station to your tank's fill nipple. Most fill stations have a valve, button, or lever to open the air flow to an HPA tank. Some systems use a booster pump to fill to maximum pressure. Open the valve to allow air to flow into the HPA tank.
  
  Close the valve as the tank approaches it's maximum pressure. Do not overfill the HPA tank. Allow excess air to bleed from the line running from the fill station to the tank fill nipple. Disconnect the tank fill nipple from the fill station.