Appliance IQ: Kitchen

Dishwasher is leaving gritty residue

Is there a gritty residue on your plates, glasses and other items even though they’ve already gone through a cycle in the dishwasher?

If so, this article should help you navigate the process of identifying the typical reasons behind your dishwasher leaving a gritty residue while offering insight into how to resolve the issue.

What Causes a Gritty Residue in a Dishwasher?

Glass with a gritty residue on a rack in a Whirlpool dishwasher.

Let’s review a few of the typical reasons as to why your dishwasher is leaving a gritty residue:

  1. Clogged drain
    A clog could be preventing residue from being properly filtered and then discarded. 
  2. Using too much detergent
    It’s important to precisely measure detergent. Also, make sure you are aware of your  water supply and if you use a water softener. This should help you determine how much detergent to add.

Remember, softened water needs less detergent than hard water.

  1. Using the wrong detergent
    Trying to clean dishes with a soap not intended for a dishwasher, like hand soap, could result in a gritty residue. We recommend only using automatic dishwasher detergents. 
  2. Not regularly cleaning your dishwasher
    Do you  clean your dishwasher at least once a month? If not you should consider doing this as it can help the tub and filters remain free of residue. Dirty filters may prevent the dishwasher from effectively breaking down food particles. 
Someone places an affresh pod in the detergent compartment in their Whirlpool dishwasher. A package of affresh cleaner is on the counter next to the sink. The kitchen has a Whirlpool fridge and grey cabinets.

affresh® cleaner can get rid of any mineral build-up to ensure that your dishwasher and what comes out of it look amazing.

Troubleshooting Your Dishwasher Leaving Gritty Residue

The filter of a Whirlpool dishwasher.

An unclean dishwasher filter could prevent food particles from breaking down. 
Check the bottom centre of your dishwasher to locate the filter.

You can tell if your filter needs to be cleaned if you see or experience the following:

  • Objects or soils are on the upper filter assembly.
  • The cleaning performance isn’t optimal.
  • Dishes feel gritty.

Certain models, including some from Whirlpool brand, have a triple filter system made up of an upper filter assembly and a lower filter. 

The upper filter assembly keeps oversized items, foreign objects and very fine food particles out of the pump.

The lower filter prevents food from recirculating and clinging onto dishes and other items.

Recommended Time Intervals to Clean Your Filter

per week
Pre-load dish treatment
Wash Scrape and Rinse Scrape only Do not scrape and rinse
1-3 12 months 12 months 6 months 2 months
4-7 12 months 12 months 6 months 1 month
4-7 12 months 6 months 3 months 2 weeks
8-12 12 months 6 months 3 months 1 week

To clean your dishwasher’s filter, be sure to follow your dishwasher use and care instructions. These instructions should cover both removal and reinstallation.

For Whirlpool® dishwashers, remove and reinstall the filter by: 

  1. Turning the upper filter assembly a quarter turn counterclockwise and lifting it out.
  2. Lift the lower filter in the circular opening just a bit and pull forward to remove.

Never clean a filter with a scouring pad, wire brush or anything with an abrasive surface. Each could damage the filter. Try rinsing the filter under running water until it is just about clean. If there are stubborn soils or calcium deposits, a soft brush may be required.

Once you’re done, you will need to reinstall the filter by doing the following:

  1. Place the lower filter under the locating tabs at the bottom of the dishwasher. Line up the round opening for the upper filter assembly with the circular opening in the bottom of the tub.
  2. Insert the upper filter assembly into the circular opening in the lower filter.
  3. Carefully rotate the filter clockwise. You should stop once it drops into place. Next, continue to rotate until the filter is fully locked. If the filter can still easily turn, you need to continue turning the filter clockwise until it drops and locks.

The upper filter assembly arrow does not have to line up with the arrow in the lower filter. All that matters is that the filter is locked.

Remember that your dishwasher can be damaged if the filters are improperly installed. 

Follow these steps to rinse and replace a clogged dishwasher:

  • Rinse it under water to get rid of any food particles and debris. 
  • Next, gently scrub the filter with warm water and a soft brush.   
  • Lastly, replace the filter and put the cover back on.

Check Your Drain Hose and Drain Motor
If your dishwasher still isn’t working, you may have a broken drain motor or a clogged drain hose. These can result in standing water and a gritty residue. If you suspect that either of these is the case, we recommend you contact a professional. For Whirlpool brand dishwashers, you can book a service appointment here.

An appliance repairman inspects the filter of a Whirlpool dishwasher. Their toolbox is on the floor and a dishwasher rack is in front of the appliance.

If water is not draining at end of a cycle, this could be caused by:

  • A problem with the dishwasher air gap. This part is designed to allow air in so that the dishwasher can drain without creating a vacuum.
  • Review the air gap manufacturer's instructions for how to check for any clogs or blockages in the air gap and the air gap vent.
  • A type of obstruction, which may be caught in the drain or the garbage disposer. 
  • The garbage disposer knockout plug may still be in the disposer inlet. To clear the obstruction, try running the disposer. 

Our lives depend on our kitchen appliances working as intended, and you definitely don’t want your dishwasher leaving behind a gritty residue. 

We hope this article can help you work through this issue and land on the right solution. Of course, if you’re still unsure or uncomfortable fixing it yourself, go ahead and book a service appointment.

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