You placed a web order for two PiezoFlush cleaning cartridges. MK and LK which both have the same instructions directly on the product page. We provide this information pre-sale so customers can make informed decisions. On the product page, http://shop.inkjetmall.com/PiezoFlush-cartridge-combo-for-Epson-7900-9900-MK.html, click on Additional Information and read the instructions for use. It will explain how to Flush your printer. The instructions are thorough.
All of the ink channels are located in one print head. Epson does not manufacture any printers with independent channel control. Some manufacturers produce printers which have a print head for each color and the manufacturer installs a mechanism for clearing a single channel. Epson does not do this. In order for you to flush the two channels that you purchased product for, you will need to follow the Initial Fill procedure. The other eight channels will draw fluid from the ink cartridges that are presently installed when the print head has the strong suction procedure of the Initial Fill. You can choose to either flush the entire printer with a set of carts or one or more channels by installing only in those positions. But you will lose ink in the other positions. This is how Epson designed their printer maintenance procedures. Whether you do it yourself or pay for a technician to visit you, the only way to effectively flush a channel on a X890, or X900 printer is by Initial Fill.
There is a way to use QTR to flush a single channel without losing ink in the other positions, but it is not effective for clogs or trying to free up matter in your ink exchanger or print head. It is used to flush out one ink in order to install another. You will find that instruction also on our Articles / Product Manuals and Instructions page on this tech website here.
You can use the cartridge filling instructions that came with your product to correctly fill the cartridge (whether it is any of our inks or PiezoFlush, the instructions for filling are the same.) You can watch a video on how to fill your cartridge on the same product page above. Click on Videos, then click on How to Use 7890 9890 7900 9900 refillable carts.
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