This might duplicate what Eric posted on his thread , but here is what Hal sent me as causes of head issue:
Bad head cause: 1. Bad ink, 2. Expired ink. 3. Bad/dirty cap/pump unit. 4. Bad/dirty flush box. 5. Bad/dirty head cleaner. 6. Bad/dirty damper. 7. Infrequent use of printer. 8. Temperature and humidity. 9. Wrong setting of the paper profile. 10. Paper suction is bad. 11. Back suck. 12. Air in head or ink tube. 13. Leaking at ink supply. 14. Bad ink cartridge. 15. Near the end of the roll paper especially the thick media (curve up). 16. Paper dust, dust and pet hair. 17. Third party or specialty ink. 18. Clean and place moist paper towel under the head. 19. Clean head outside the printer. 20. Short out the head when inserting the head cable. 21. Bad head cable. 2. Wrong ink color in other channel.
Ways to clean clog:
1. Cleaning solution. I tried many brands and most of them do not work. Epson cleaning solution is better but do not work all the time. Use it at your own risk. (It comes in big bottle and I can repack it in a smaller size and sell to you. It is good for minor or partial nozzle clog only. I would say 75% times work. Email me if you need some)
2. Warm water. Do pretty good job. I don’t like other chemicals.
3. Clean Flush box and cap unit frequently. Back suck is often found in clogged flush box and cap unit.
4. Air leaking in ink cartridge, ink supply, ink tube, and damper introduce air bubbles creating drop out while printing. (use POWER CLEAN to eliminate the problem)
5. Infrequent use. Do not use automatic nozzle check. Create color pattern for each color (say 1” square of each color). Print the pattern every other day. The main purpose is flush out the old ink sitting inside the print head and put fresh ink in it to protect the head from clogging. This method would not waste ink. If the pattern is not perfect, then perform head cleaning.
6. Temperature and humidity. It is not that critical unless the printer is located in a bad environment.
7. Wrong setting, paper suction and condition of the paper (curve up) may scratch and damage the print head.
8. Dust problem: Don’t use can air. You’ll blow more problems into the printer. Use a vacuum cleaner to remove dust, pet hear and dirt.
9. When cleaning head outside the printer, make sure the head plate would not touch anything. When cleaning the head with cleaning solution, make sure the electronic contacts do not immerse below the liquid surface.
10. Check head cable for damage.
11. Back suck or bad head because adjacent channels are open. Replace head
Head cleaning method:
1. Pair cleaning – Most efficient use of ink.
2. Power cleaning – Best way to remove air from the system. Clean nozzles drop off while printing.
3. SS cleaning - Using strong built in ultrasonic element to break up pigment particles in the head nozzles.
Need parts, need cleaning solution or more question, Email email@example.com