Error 6: Unblocking the Drain Pump on A Commercial Dishwasher/Glasswasher

Posted by Ollie Nelson on

Disclaimer: Please be aware that this tutorial is applicable only to the Nelson Advantage glasswasher/dishwasher series and the Nelson Speedwash dishwasher series. It does not apply to the Nelson Speedwash glasswasher series.

Starting Off

Error 6 is a fault message which appears on the Advantage and Speedwash + range of commercial dishwashers and glasswashers when the drain pump is obstructed by debris like shattered glass or crockery, fruit pieces from beverages, or food waste. When this problem occurs, the phrase 'ERROR 6' will show on your machine's display, the cycle start button will glow red, and the machine will be unusable until the obstruction is cleared.

Advantage & Speedwash Error 6 Display

Essential Tools:

  • A Phillips screwdriver
  • A bucket
  • A pint glass or small jug (for scooping out water)
  • A water-absorbent cloth

Step-by-step Guide

Step 1: Power Down

Ensure your safety by disconnecting the machine from its power source. Turn it off at the wall isolator (three-phase connection) or unplug it from the socket (single-phase connection).

Step 2: Filter Removal

Take out the main wash tank filters from the machine and set them aside. You'll need to reinstall them later.

Removing filters from the machines

Step 3: Empty the Tank

Using the glass/small jug, bail out any water in the wash tank into the bucket. Aim to remove as much water as possible to facilitate the next step.

Bailing water out of the wash tank                       Bailing water into the bucket

Step 4: Dry the Sump

Soak up any leftover water at the bottom of the sump with the cloth and wring it into the bucket until the sump is completely dry.

Using cloth to remove residual water from the sump                      Using the cloth to remove residual water from the sump

After removing the water, the sump should look as follows:

Empty wash tank and sump

Step 5: Unscrew the Drain Pump Cover

Use the Phillips screwdriver to unscrew the middle of the sump (circled). Important: ensure you only remove the middle screw, not the ones around the sump's outer part, to prevent leakage.

Removing the screw from the drain pump cover

After removal, place the screw in a secure location as you'll need to reattach it later.

Keep the screw from the drain cover safe

Step 6: Remove the Drain Pump Cover

To do this:

  1. Insert your finger into the sump's middle hole and your other finger on the drain cover's latch.
  2. Push the latch forward to release the cover and lift it out. If it's tightly secured, you might need to wiggle it to loosen it.

Removing the drain cover - step 1                   Removing the drain cover - step 2

After removal, keep the drain cover safe with the earlier removed screw for reattachment later.

 Store drain pump cover and screw safely together

Step 7: Clear the Blockage

Remove any debris obstructing the drain pump's fan. Typically, it's a piece of glass or plastic that hampers the drainage pump impeller's rotation.

Remove and debris from the fan

Step 8: Reassemble

Refit the plastic drain pump cover, ensuring it's correctly positioned. Secure the drain pump cover in place by refitting the screw. 

Refit the drain cover            Refit the screw to secure the drain pump cover

Place the filters back into the machine's wash tank.

Refit the filters to the wash tank

Step 9: Power Up

Close the door, turn on the machine, and let it fill.

Step 10: Confirmation

You'll know the issue has been resolved if the start button illuminates green and the Error 6 message no longer appears on the display.

Machine on and working

Final Thoughts 

By following these step-by-step instructions you should be able to resolve Error 6 without the need for an engineer. However, if you are unable to resolve the fault, feel free to call the Nelson Support team on 020 8993 6199 or email and we will be happy to assist you.

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  • Thank u so much Ms dana, for your prompt assistance. The manual that u sent really helped me to figure out the error and by following the steps that r made so easily to understand by mentioning the pictures as welll it really was easy to fix . Thank you so much for making life so easy .

    Rajesh on

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