Detailed Printhead Nozzle Clog Clearing & Repair Procedure (Highly Recommended for Reference)

Detailed Printhead Nozzle Clog Clearing & Repair Procedure (Highly Recommended for Reference)

Table of content.

Printhead Nozzle Clog Cleaning & Restoration Process

During inkjet printing operation, improper use, environmental factors, or insufficient maintenance may cause nozzle clogging or jet misdirection, leading to printing defects such as banding, ink misting, tailing, or missing lines.

Below are examples of abnormal printhead conditions, along with step-by-step cleaning and unclogging procedures, required tools, and important precautions. We hope this guide will be helpful to you.

 

 

Abnormal Printhead Images

Abnormal printhead examples
 (Ricoh Gen5 printhead shown; applicable to other printheads as well)

  • Abnormal Printhead Image 1

  • Abnormal Printhead Image 2

 

Abnormal Printhead Status Images

  • Abnormal Status Image 1

  • Abnormal Status Image 2

 

Printhead Condition After Cleaning

  • Post-Cleaning Status Image 1

  • Post-Cleaning Status Image 2

 

Materials Preparation Before Cleaning & Unclogging

Prepare the following items before starting:

  • Ultra-fine microfiber lint-free wipes
     (Rough lint-free cloths may shed fibers, cause residue, streaking, or nozzle blockage)

  • Dedicated printhead cleaning solution
     (Select according to printhead model and ink type; illustrated example is UV ink cleaning solution)

  • Syringes, ink tubes, and butterfly filters
     (Assemble suction devices; use separate syringes for three different liquids)

  • Dedicated red unclogging solution for printheads
     (Use model-specific solution if available; otherwise, use a general type)

  • Glass measuring cups
     (At least three cups ≥50 ml, each for a different liquid)

  • Ink tube plugs/connectors
     (Choose suitable internal or external threaded fittings according to tube diameter and filter specifications)

  • Distilled water

  • Stainless steel container or blue plastic tray
     (For waste cleaning liquid, red solution, and distilled water; stainless steel preferred)

  • Protective gloves and safety goggles
     (Personal protective equipment)

 

Printhead Cleaning & Unclogging Procedure

Step 1: Flush Ink with Cleaning Solution

  • Draw 30–50 ml cleaning solution into a syringe

  • Inject through the ink inlet to flush out ink

  • Use an empty syringe to slowly push out the cleaning liquid

  • Observe ink/solution flowing evenly from the nozzle surface

  • Recommended pressure: <50 kPa
     (If possible, connect a pressure gauge between the syringe and tube.)

Pressure conversion:
 1 psi = 6.895 kPa

 

Step 2: Rinse with Distilled Water

  • Draw 30–50 ml distilled water

  • Inject through the ink inlet to rinse residual cleaning solution

  • Slowly push out excess distilled water using an empty syringe

 

Step 3: Inject Red Unclogging Solution

  • Draw 30–50 ml red unclogging solution

  • Inject through the ink inlet until solution slightly overflows from the nozzle surface

  • Plug other ink inlets/outlets to prevent leakage

  • Place the printhead on a clean lint-free cloth and let it soak for ~10 minutes

  • Slowly push out the red solution using an empty syringe

 

 

Step 4: Rinse Again with Distilled Water

  • Inject 30–50 ml distilled water

  • Slowly push out remaining liquid

 

Step 5: Final Cleaning Solution Flush

  • Inject 30–50 ml cleaning solution

  • Slowly push out all remaining solution

 

Step 6: Reinstall the Printhead

  • Install the printhead carefully following correct installation procedures and precautions

 

Step 7: Refill Ink & Prime System

  • Refill ink

  • Prime ink lines to remove air bubbles

 

Step 8: Wipe & Maintain Printhead

  • Perform standard printhead wiping

  • Print a nozzle check pattern

 

Step 9: Print Test Pattern & Verify Results

  • Evaluate improvement after cleaning

  • If results are insufficient, repeat Steps 1–8

  • In most cases, 95%+ nozzle clogs can be resolved with 1–3 repetitions

If clogging persists after multiple attempts, use a professional printhead cleaning machine (also known as a “printhead recovery doctor”).

 

 

About Professional Printhead Cleaning Machines

  • Cleaning principles are similar to Steps 1–5

  • Allows precise pressure control and optimized cleaning programs

  • Provides superior unclogging performance

  • Suitable for batch cleaning of printheads

Professional repair companies commonly use such machines.
 If you prefer not to purchase one, you may send the printhead to a repair service.
 Typical cost: USD 100–200, often with no charge if repair fails.

 

 

Summary

The procedures described above apply only to nozzle clogging caused by ink residue, foreign particles, or ink curing deposits.

This method does NOT apply to:

  • Printhead circuit damage

  • Internal electronic component failure

  • Mechanical damage due to collision or scraping

For such cases, professional repair or replacement is required.

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