Instruction for refillable cartridges alternative for Brother LC-421 inkjet cartridges

The original Brother LC-421 inkjet cartridges can be replaced by refillable Fill In cartridges. These alternative single tank cartridges have a built in port for filling in the printer ink and they have a holder for the alternative ink chips. The ink chip identifies the cartridge towards the printer and delivers the necessary information for the displayed ink level plus the ink level related warning messages. The set of refillables is suitable for the Brother® printers:
DCP-J 1050 DW, DCP-J 1140 DW, DCP-J 1800 DW, MFC-J 1010 DW.

The refillable single tank cartridges are made from see-through plastic material and provide You with the opportunity to check on the physical ink level inside the cartridges very easily. The supply of ink towards the Brother® printer is provided by the cartridge´s ink port which is equipped with a valve. This self-closing valve ensures that the cartridge is not leaking any ink when it is taken out of the printer.
The advantage of the easiest ink refill is achieved through the filler opening (colored plug) located on the front of the cartridge. Directly below is the vent (transparent plug) – this ensures that the ink volume used during printing is compensated for by air and that no negative pressure builds up inside the LC-421 fill-in cartridges. The ink filler opening must be closed and the vent open during printing.

For filling up the refillable cartridge for Bother® LC-421, LC-421 XL remove the plug outof the fill port. Please keep that plug to be able to close the port again after filling the cartridge.
The following quantities if ink are suitable for the refillable cartridges:
BLACK - 12,5 ml
CYAN / MAGENTA / YELLOW - 7 ml to 10 ml
We recommend that the ink level inside the cartridge does not exceed the fill port when the refillable cartridge is positioned as it is going to sit in the printer. This ensures that no ink is leaking from the cartridge out of the fill port. Fill the desired amount of ink into the cartridge carefully - when using a refill syringe in combination with a cannula pay attention to not inflict any damages with this sharp needle. Close the fill port when the refillable cartridge is fully filled.

The cyan Fill In cartridge is filled with ink and equipped with a new ink chip for LC-421 XL CYAN. The cartridge is now ready for beeing used in the printer. Make sure that the ink port is closed and the plug has been removed from the vent. Slide the Fill In cartridge into the correct cartridge position in the cartridge compartment in the printer and click the cartridge firmly into place by pressing on the back of the cartridge. Thanks to the new ink chip, the cartridge is displayed with a full ink level.
Note that thedisplayed  ink level indicator is an estimated value. Because of this, please check regularly how much ink is actually left in the cartridge - make sure that there is always sufficient ink in the cartridge. In the case that the chip signals that the cartridge is empty but there is actually still ink in the cartridge, you will need to equip the refillable cartridge with a new, alternative chip. Ideally, you should also refill the cartridge then.