Epson EcoTank Nozzle Loss After Power Cleaning: Maintenance Box Filling Fast, Damper Priming, and Tank Venting Explained

Question: I replaced the maintenance box, but it filled up again quickly. Now black is failing and yellow never improved-should I re-prime or replace dampers, and are these parts compatible?

Thanks for getting back to me. I replaced the maintenance box, but I've already filled it up and need to order another. Since installing it, I ran a power cleaning and then a few regular head cleanings. I've done nozzle checks and controlled prints, but now black has started to fail and yellow has never improved at all.

I want to try replacing something or re-priming the dampers because I suspect the yellow line may be dried/clogged. Can you confirm whether these items will work for my machine?

• 8 PCS Tool: 4x 10ml Syringe + 4x Extra Long Blunt Needle for Cartridge Refill CISS CIS (AS-SY10-X4)

• Used Genuine Warranty-Friendly Ink Supply Tubing for EcoTank and SuperTank Printers ET-2750 ET-3750 ET-4750, and more (No Return)

• 4PCS Used Genuine Epson Dampers for ET-2750, ET-15000, ET-3750, ST-2000, ST-4000, ST-4550, L1800, and more (No Return)

Also, I couldn't find a video on cleaning dampers. Is there a recommended way-like warm water soaking?

Finally, can you clarify what you mean by: "Verify tank venting and ink levels... a closed vent can mimic a clog"? I keep the tank tops closed because I thought that's how it's supposed to be. Is priming the dampers with syringes the best way to fix this issue?

Answer: 

Compatibility: Yes-those parts/tools are generally suitable for the EcoTank damper/tubing workflow

Based on what you listed, yes, those items will work for the type of damper priming and ink-line servicing you're describing:

• The 10ml syringes + extra-long blunt needles are appropriate for controlled priming/pulling ink through a damper line.

• The EcoTank/SuperTank ink supply tubing you listed is the correct style used in many Epson EcoTank platforms (as long as you match inner diameter and connector style).

• The used genuine Epson dampers listed for ET/ST/L-series are typically compatible across multiple models within that architecture.

The biggest practical point: even "compatible" dampers and tubing can still vary by connector shape, hose diameter, and mounting orientation, so physical matching matters. But from a functional/usage standpoint, you're looking at the correct category of parts.

Why the maintenance box filled up so quickly after power cleaning

This part is actually expected. Power Cleaning and repeated head cleanings dump a large amount of ink into the waste system. That ink exits through the cap/pump assembly and ends up saturating the maintenance box rapidly. In other words, when the printer is doing a lot of forced purging, the maintenance box becomes the "ink bill."

Important takeaway: if nozzle checks aren't improving after multiple cleanings, continuing to power clean often creates a cycle of:

• more waste ink → maintenance box fills fast

• more stress on ink delivery balance → other colors can start dropping (like your black now)

• still no improvement if the root cause is air leak, dried line, damper restriction, or venting issue

So your instinct to shift from "more cleaning" to "check delivery/prime/replace a part" makes sense.

Yellow never improves + black now failing: what this pattern usually points to

When one color (yellow) never responds, and then another (black) starts failing after heavy cleaning cycles, it often suggests one or more of the following:

1. Air ingestion / air leak somewhere in the ink path
   A tiny leak at a fitting, damper seal, or line connection can cause intermittent starvation. It may show up worst on one color first (often yellow because it's visually obvious on nozzle checks), then spreads.

2. Dried/restricted yellow line or damper
   If the yellow tube is partially dried or the damper filter is restricted, cleanings may not overcome the blockage. The pump can't reliably pull fresh ink through.

3. Venting or negative pressure problem
   If the tank isn't venting correctly, the system behaves like it's "clogged" because ink can't flow consistently. The pump ends up pulling vacuum instead of ink.

4. Cap station / pump issues (less commonly just one color, but can contribute)
   If the cap isn't sealing well or the pump draw is inconsistent, you can get persistent missing nozzles and excessive waste ink without true recovery.

Tank venting explained (and why "tops closed" can still be correct... or not)

Your confusion here is totally understandable because EcoTank designs differ.

What "venting" means in plain terms

For ink to flow from the tank to the head, air must be allowed to enter the tank to replace the ink volume leaving it. If air can't enter, the system can develop negative pressure (vacuum), and ink flow becomes weak or stops-this can mimic a clog.

"I keep the tank tops closed-should they be?"

On many EcoTank models, the large outer lids can remain closed, but there is usually an actual vent mechanism (a vent plug, valve, or internal vent channel) that must be in the "open/printing" position depending on the model. So "lid closed" doesn't necessarily mean "vent closed"-but if the vent itself is closed, ink flow can starve.

The quick venting test (this is the key point)

Here's the simplest functional rule:

If you can pull ink through the damper line with a syringe (steady ink flow, not just bubbles), the tank is venting correctly.
If you cannot pull ink and it feels like drawing against a vacuum, the tank/line is not venting correctly (or there's a blockage).

That's essentially the diagnostic principle:

• Ink pulls easily → venting is OK

• Hard to pull / strong resistance / mostly air or nothing → venting issue or restriction

This is why priming with a syringe is not only a "fix attempt," but also a test.

Is priming the dampers with syringes the best next step?

Yes-priming is a good next step when you suspect a dried line or air in the system, because it does two things:

1. It confirms whether ink delivery is physically possible (venting + pathway integrity).

2. It restores ink to the damper and line so the head isn't trying to print with air pockets.

What you want to see during priming:

• a smooth pull of ink (not foamy, not mostly bubbles)

• consistent ink presence in the damper

• after priming, nozzle check should show at least some improvement if the head is still healthy

If priming cannot establish stable ink flow for yellow, that strongly supports replacing the yellow damper and/or servicing the yellow line.

Can dampers be cleaned in warm water?

In general, we do not recommend soaking dampers in water as a "standard cleaning" method. Dampers contain internal membranes/filters designed for ink-not water-and introducing water can:

• dilute ink residues into sludge,

• leave moisture trapped inside the damper,

• promote contamination or inconsistent flow,

• potentially damage the internal filter/media.

If a damper is suspected to be restricted, it's often more reliable to replace it than to try to wash it. Used dampers can work, but consistent performance usually comes from good flow and good seals-so if you're troubleshooting a stubborn color like yellow, swapping in a known-good damper is often a smarter move than soaking.

Printer problems can be complicated because they're hands-on, and small physical details make a big difference. For that reason, we're not able to provide remote troubleshooting, step-by-step repair coaching, or direct support for printer repairs. We do offer in-person evaluation and repair through our local diagnostic facility: Printer Repair Service (https://bchtechnologies.com/printer-repair-service). Due to high demand, we operate first-come, first-served, and it may take a few weeks before you can drop off your printer. Our services can cover either the whole printer or specific parts, with clear instructions on how to proceed, but we also recognize our rates may not be the most economical option. Because of that, we strongly encourage self-help through online research. A great place to start is YouTube and our channel homepage: BCH Technologies on YouTube (https://youtube.com/@bchtechnologies). Use the search icon next to "About" on the right-hand side of the menu bar to locate the most relevant videos quickly. We receive many questions daily asking for the right video, and after years of uploads it's tough to remember every single one-YouTube search is the fastest approach, and it may also recommend helpful videos from other channels.

Thank you again for reaching out, and thank you for your continued support. We truly appreciate it, and I hope the venting test and damper priming guidance helps you move forward with confidence.