I have a 4900 that prints a 99.99 % perfect nozzle pattern except for one little spot in the green. It's been that way for two years. I never noticed any detrimental effect on print output. However, the fact that it didn't print a perfect pattern drove me crazy. Over the past 24 months I have tried everything short of changing the print-head to clear that stubborn little clog, but nothing worked.
My printers are located in a basement office that tends to develop a musty smell during the year. I also have a MMA academy and use a ozone generator for clearing the air of smells and removing those impossible sweat odors from boxing gloves, pads, gis, etc. Yesterday, I decided to give my print room an ozone shock treatment. Guess what? My printer started printing a perfect pattern.
Not sure if the ozone had an effect or it was just coincidence.
