Epson WF-7720 Printhead Replacement: Fixing Error 00031 and "Print Head Might Need Maintenance" After Installing a New Head

Question:
I replaced the printhead on my Epson WorkForce WF-7720 by following your video guide for the T1881 printhead replacement. The printer no longer shows error code 00031, which was the original issue, but after installation it displayed a "print head might need maintenance" message. I pressed OK and the printer continued normally, but when I ran a nozzle check, it did not print a single line. I also tried a printhead cleaning and another nozzle check, but nothing changed. I bought the replacement printhead as a "new" part from AliExpress, so I am wondering whether it may not actually be new or whether it is somehow bypassing the original error.

Answer:

The fact that your WF-7720 is no longer showing error 00031 is actually an important clue. In many Epson models, 00031 points to a printhead-related electrical or communication fault. That can mean the original printhead had an internal failure, a short, or a damaged circuit path. Since the new head allows the printer to power up past that error, it suggests the replacement printhead is at least communicating well enough with the mainboard to avoid triggering 00031.

However, the new message - "print head might need maintenance" - along with a completely blank nozzle check tells us the issue has shifted from an electrical fault to an ink delivery or priming problem. In other words, the printer may recognize the replacement head, but ink is still not reaching the nozzles.

In most cases like this, the replacement printhead is filled with shipping fluid or preservative liquid. That fluid is often thicker or behaves differently from regular ink, so it does not always clear out with a simple nozzle check. A normal cleaning cycle will often remove it, but sometimes the head needs a little help to get fully primed.

Here is the most likely explanation: after installation, the printhead is physically present and electronically accepted, but the nozzles are still dry, partially air-locked, or filled with shipping fluid rather than ink. That is why the printer can move through its routines without showing 00031, yet still produce a completely blank nozzle pattern.

A good next step is to perform a park and prime procedure.

To do that, turn the printer on and allow the printhead to settle naturally on the capping station. It is fine to do this with the power on. Once the head is parked, connect a syringe and tube to the printer's waste line and gently begin drawing. Start by drawing a small amount of air, then continue toward 4 to 6 ml. At that stage, you should normally feel a slight resistance.

What you feel during this step is very useful diagnostically:

• If you draw only air with little or no resistance, the printhead may not actually be parked on the cap correctly, or the capping station may not be sealing properly.

• If you feel total resistance and cannot draw anything, the capping station may be clogged.

• If you hear the damper membrane crinkle or feel the suction begin to change after a few milliliters, that usually means the nozzles are starting to open and the ink path is beginning to respond.

From there, slowly continue drawing until the syringe reaches the 10 ml mark, watching the fluid level carefully. Because the syringe is held upward, that usually means you have drawn roughly 4 ml of ink by the time the black rubber reaches around the 6 ml mark. Hold that position for about 10 seconds, then release.

After that, run the printer's regular cleaning cycle, not an aggressive one. Avoid doing strong cleaning within the next 12 hours, and do not run repeated cleanings back to back without giving the printer time to rest. Too many consecutive cleanings can overwork the pump system, overfill the waste path, and sometimes make diagnosis harder instead of easier.

A few additional points may help:

First, if the replacement printhead was sold as "new," that does not always guarantee true factory-new condition. Some aftermarket heads are refurbished, cleaned, or electronically altered. Even so, a refurbished head can still work if it is mechanically sound and can be properly primed. The blank nozzle check does not automatically prove the head is bad; it often just means the head has not started drawing ink yet.

Second, if the printer still prints absolutely nothing after park-and-prime and a reasonable waiting period, check the rest of the ink path. On these Epson models, problems with the dampers, ink lines, capping station, or pump assembly can prevent a good printhead from receiving ink. A failing cap seal or weak pump can produce symptoms that look exactly like a dead printhead.

Third, if you are using thicker inks such as DTF ink, priming becomes even more important because those inks do not move as easily as standard aqueous ink. They often need a little more help to overcome air pockets or preservative fluid left inside the head.

So in summary, your current symptoms are actually consistent with a printhead that is recognized by the printer but not yet inked up, rather than one that is necessarily bypassing error 00031. The disappearance of 00031 is a positive sign. The remaining issue is most likely incomplete priming, trapped air, shipping fluid, or a maintenance-station problem preventing suction.

Printer repair is often difficult to diagnose remotely because so many of the causes are mechanical and hands-on. For that reason, we are not able to provide step-by-step remote repair support or full troubleshooting beyond general guidance. We do offer service through our printer repair facility (https://bchtechnologies.com/printer-repair-service). Because demand is high, repairs are handled on a first-come, first-served basis, and it may take a few weeks before we can schedule a drop-off. We can work on either an entire printer or a specific part, with instructions provided for each option. That said, we understand our service may not be the lowest-cost route, so self-guided research is often the best first step. We strongly recommend checking YouTube, including our BCH Technologies YouTube homepage (https://youtube.com/@bchtechnologies). Use the search icon next to "About" on the right side of the menu bar to look for videos on your exact symptom. Since we have published videos over many years, that search feature is usually the fastest way to locate the most relevant content, and YouTube may also suggest useful videos from other creators.

Thank you again for your thoughtful feedback and kind words about the video. We truly appreciate your support and your willingness to share your results, and we hope this gives you a clearer direction for what to check next.