Why Does My Epson L1800 Printhead Keep Clogging Overnight? Causes and Fixes for Repeated Nozzle Blockage

Question:
I’ve been using an Epson L1800 and have been following your videos—great work, by the way! I have a problem where the printhead gets clogged, but after I clean it manually, it works fine. However, the very next day, it's clogged again. Could this be a problem with the ink, or is the printhead defective?

Answer:
Thank you so much for contacting us—and for your kind words and support! We're incredibly grateful for your engagement with our content, especially on our YouTube channel (https://youtube.com/@bchtechnologies). Your feedback plays a crucial role in shaping the content and guidance we create for the printing community.

First, I apologize for not getting back to you sooner. I understand how frustrating printer issues can be—especially when you’ve already put time into manually cleaning and troubleshooting. These issues are urgent, but they also require careful attention, and I want to give your question the detail it deserves.

Now, based on your description, it’s unlikely that the printhead itself is defective. If it functions properly right after cleaning, but then clogs again after sitting overnight, the issue is more likely environmental or system-related. Let’s break down the most common causes:

🔍 1. Ink Quality – The Most Common Culprit

Yes, ink can absolutely be the issue. Lower-quality third-party ink may not stay in suspension and can cause settling of pigment particles inside the nozzles. When the printer sits idle, these particles settle and dry, clogging the nozzles again by morning.

• What to do: Switch to high-quality ink that is formulated for Epson L1800 or similar piezo printheads. At BCH Technologies (https://bchtechnologies.com), we offer lab-tested ink designed specifically for DTF and pigment-based systems, ensuring long-term nozzle stability.

🧼 2. Capping Station Issues

When the printer is not in use, the printhead rests on a capping station. This unit seals the nozzle area and prevents drying. If the capping station is misaligned, dirty, or not sealing properly, air will get into the nozzles and dry them out overnight—even after a perfect cleaning.

• What to do:

  • Check the rubber seals on the cap for wear or ink buildup.

  • Confirm it’s aligned properly and fully contacts the printhead.

  • Make sure it has adequate suction—nozzle checks that come out blank could mean weak suction or a clogged drain tube.

⚙️ 3. Firmware or Maintenance Cycle Failure

Some printers automatically perform light cleanings during standby periods. If the printer is turned off, unplugged, or not in sleep mode, it may skip those cycles, leading to clogs.

• What to do:

  • Leave the printer powered on overnight (in sleep mode).

  • Ensure auto-maintenance features are enabled in your firmware, if applicable.

💨 4. Negative Pressure in the Ink System

If you're using a bulk ink system (CIS) or third-party tank setup, poor pressure control can starve the printhead of ink—especially after a period of inactivity. The furthest colors often suffer most.

• What to do:

  • Prime the ink lines to ensure ink is reaching the printhead.

  • Check for air bubbles or clogs in the tubing.

  • Ensure the tanks are at the correct height relative to the printhead.

🔧 What We Recommend:

• Switch to quality ink that’s made for the Epson L1800’s micro-piezo system.

• Inspect or replace the capping station—a small part that plays a huge role in nozzle health.

• Keep the printer powered on, especially overnight, so scheduled cleanings can run.

• Manually prime the lines and monitor for ink starvation.

If you’d like, feel free to let us know what brand of ink you’re currently using and whether you're using an OEM system or a CIS setup. That would help us offer more specific advice.

Addressing printer issues can be a complicated affair due to the hands-on nature of the problems. So, we're not able to provide remote troubleshooting, suggestions, or support for printer repairs. We offer an in-person evaluation and repair service via our local diagnostic facility (https://bchtechnologies.com/printer-repair-service). Given the high demand, we operate on a first-come, first-served basis. So, it might take a few weeks before we can get your printer to drop it off. Our services are structured to repair either a whole printer or specific parts, with clear instructions on how to proceed. However, we acknowledge that our rates aren't the most economical. Thus, we highly recommend that you resort to self-help via online research. You can start by checking out YouTube or visiting our YouTube channel's homepage (https://youtube.com/@bchtechnologies). Look for specific videos using the search icon next to "About" on the right-hand side of the menu bar. YouTube might also suggest helpful videos from other channels that could assist you.

Thanks again for your message and for watching our content. You’re doing the right thing by proactively maintaining your printer—and with the right ink and care, your L1800 can run reliably for years to come. Let us know if you have any follow-up questions!