Epson EcoTank 2720 Black Ink Not Printing After Fixing Other Colors – Troubleshooting Guide

Question:

I’ve been troubleshooting my Epson EcoTank 2720 and have encountered an odd problem. The yellow and cyan were not printing, so I performed multiple cleanings, including a power wash, but the yellow and cyan still did not print. Eventually, after following a video tutorial about unclogging tubes and priming dampers, I got yellow and cyan working — now black won’t print. I also attempted to draw ink into the black damper with a syringe, but it still refuses to print, despite showing a full ink tank. Does fixing the other colors cause this, and how do I fix it?

Answer:

It was an air lock in the black ink line.

From your description, you have plenty of black ink and no sign of a blockage. The most likely suspect is an air lock in the black ink line since correcting the problem with the cyan and yellow channels caused the black to stop printing.

How to Fix an Air Lock in the Black Ink Line

Note: This is based on my experience as an engineer who has troubleshooted similar issues with printer equipment and software.

Ensure your printer is powered on and let the printhead rest on the capping station as normally.

This day of never powering off doesn’t include the printer because the printhead parks properly and is aligned to the waste ink system only when the printer is on.

Use the printer’s waste line to draw ink manually

• Attach a syringe and tubing to the printer’s waste ink line.
• Flush with 2 ml of air.
• Here’s what to watch for:
• At 1.5 ml, you should feel a slight resistance, which means the ink is flowing.
• If you pull air in, it means:
• The printhead was not parked correctly.
• There is a rupture in the capping station’s seal.
• If you encounter total resistance and cannot draw air or ink, the capping station could be blocked, preventing ink movement.

Listen for the Crinkle of a Damper Membrane

If you can hear the damper membrane crinkling when you draw ink, ink flows through the system and the nozzles are open.

Hold the Syringe at 2 ml for 10 Seconds

This negative pressure helps evacuate air from the system.

Run a Cleaning Cycle, but Exercise Caution

Use the printer’s internal cleaning cycle to prime the ink flow even more.

Don’t perform multiple substantial cleanings together in less than 12 hours—this can cause more ink or other airlocks to flood.

If the black still doesn’t print after one cleaning cycle, give the printer a few hours to rest and try again.

Further Troubleshooting Steps

✅ Inspect Ink Lines for Leaks

Check the tubing and connections for air leaks that may impede the suction.

✅ Check That Capping Station Is Not Blocked

If the ink is not flowing correctly, even after several priming attempts, remove the head and check that the capping station isn’t clogged and requires cleaning or replacement.

✅ Don’t Overdo the Syringe Method

Manually pulling ink can help, but doing it aggressively or often can corrupt dampers or introduce more air.

Need Further Help?

Printer troubleshooting is complex, because it involves doing things to it directly. Sadly, we do not provide remote repair support. But we do offer in-person diagnostics and repairs via our BCH Technologies printer repair facility (https://bchtechnologies.com/printer-repair-service), which is operating on a first-come, first-served basis due to high demand; drop-off scheduling may take a few weeks.

As for our repair service, we know not everyone has the luxury of available time and/or funds, we suggest googling "how to fix"(insert issue) to do-it-yourself. I have researched and provided numerous tutorials on various printer problems on our YouTube channel (https://youtube.com/@bchtechnologies). You can find the search option by pressing the magnifying glass icon beside "About" on our channel homepage.

Thank you for your understanding and support. If you have any questions, visit our videos or contact us. Happy printing!