It's a good preventative maintenance to replace the ink dampers in PRO printers every one to two years. They are designed to filter out pigment. Under normal conditions pigment particles pass harmlessly through the screen filter. But, when printers are allowed to sit for periods of time and pigment falls out of suspension - it is possible that sheets of dislodged pigment particles will find their way into the filter. It takes only a small amount of that material to inhibit ink flow and give the impression of "clogged nozzles". When this occur, the clog jumps from nozzle to nozzle rather than being permanent (a true clog). Over long use, pigment particles that have clung to the tubing eventually come off and this is another source of sheeting of pigment that can foul the filter screens. Finally, the screens themselves can eventually cause some pigment particles to cling to it. Simply, they can not last forever. They are designed to protect the print heads from expected pigment behavior.
At Cone Editions Press, we change our dampers for fresh ones every year. We never want to encounter micro-flow issues that might make slight changes in color - or cause us production headaches. The operation takes less than an hour. Dampers are usually $20 or less depending upon the model. For our Roland 64" printer - they provide a simple cover that is lifted so the end-user can change new dampers and new wiper blades, and even allows the end-user to wipe the print heads with a swab. Epson on the other hand, keeps its PRO printers more as consumer models in which this type of maintenance is only provided by service calls. The service manual will allow almost anyone to repair or maintain their own PRO printer. With it, the Epson PRO printer is as useful to a production environment as a Roland, Mimaki or Mutoh printer that use the same Epson Piezo print heads - but aim their printer products at professionals.
Know your equipment and learn how to perform routine preventative maintenance that includes damper replacement, wiper blade replacement, capping station cleaning, ink drain tubes cleaning.