Remove the Cartridges

• 1). Turn on the HP 3915 printer and flip open the cover on the front.
  
  
• 2). Release the paper tray down from in front of the cartridges. The cartridges will slide out into the open.
  
  
• 3). Press down on the edge of the right cartridge and pull it out of the printer. Do the same for the cartridge on the left.
  
  

Refill the Cartridges

• 1). Place the black and color cartridges upright on top of several layers of paper towels.
  
  
• 2). Remove the manufacture's label from the top of both of the cartridges.
  
  
• 3). Fill a plastic syringe with 5 ml. of black printer ink and insert it into the refill hole on the top of the HP21 black printer cartridge. Slowly release all of the ink into the cartridge.
  
  
• 4). Fill a plastic syringe with 5 ml. of magenta printer ink and insert it into the refill hole on the top center of the HP22 color cartridge. Slowly release all of the ink.
  
  
• 5). Fill a plastic syringe with 5 ml. of yellow printer ink and insert it into the refill hole to the bottom left of the magenta refill hole. Slowly release the ink.
  
  
• 6). Fill a plastic syringe with 5 ml. of cyan printer ink and insert it into the refill hole to the bottom right of the magenta refill hole. Slowly release the ink.
  
  
• 7). Replace the labels to the top of both cartridges and allow them to rest for eight hours before returning them to the printer.