Although dishwashers are one of the best inventions ever, especially after a large family meal, there are simply some things that aren’t meant to be washed in your dishwasher. The unfortunate truth is that hand washing is alive and well when it comes to the following items.

Acrylic or Plastic Dishes

Your plastic ware can be fun, colorful, and handy when it comes to casual dining but acrylic ware can’t withstand the high temperatures of your dishwasher. It will fade and crack and just not be fun anymore.

Sharp Knives

The action of the dishwasher can dull your good sharp knives. Always wash these by hand.

Nonstick Pots and Pans

You didn’t know? Unless your manufacturer specifically says their products are dishwasher safe, most nonstick coating will suffer from flaking and peeling is continually washed in a dishwasher.

Cast Iron Cookware

Perhaps you’ve tried this already and ended up with a rusty mess. Your cast iron should never see the inside of the dishwasher. Cast iron takes a long time to season properly. Your dishwasher will strip it of your hard work in a flash.

Aluminum Cookware

Check the manufacturer to see if your aluminum is dishwasher safe. In most cases, aluminum just can’t stand up to the heat of the water inside your dishwasher and can end up dull and discolored.

Dishware with Metallic Decorations

The temperature and water motion inside a dishwasher can be harsh to some dishes. This is especially true for those that have metallic decorations or trim. This is also true for any hand-painted dishes or gold colored flatware.

Pressure Cooker Lids

Stovetop pressure cookers, electric pressure cookers, and Instant Pot cookers are great devices but don’t put the lids in the dishwasher.


Some crystal can get cloudy over time. Crystal also has a tendency to crack or break with the high temperatures inside a dishwasher.


Wood cutting boards, bowls, and spoons should be hand washed. The hot water used by your dishwasher can warp or crack wood.

Insulated Drink ware or Travel Mugs

Insulated drinking vessels rely on a vacuum seal to maintain their insulation qualities. The high temperatures in your dishwasher can damage that seal.

Measuring Cups

If you measurements are printed on the side of your measuring cups, dishwasher detergent will eventually remove the printing. Then you have a set of useless measuring cups.

Copper, Brass, Bronze, or Pewter Objects

It may be tempting to put things made of these metals in the dishwasher but they can become discolored and pitted. Don’t ruin your good items made of these metals.


Antiques that are priceless should be hand washed. Always.

Your dishwasher is a time saver, for sure. But the dishwasher uses a lot of heavy motion, high temperatures, and harsh detergents to get your dishes clean. When you have any doubts, hand wash items that aren’t specifically labeled dishwasher safe.

If you are experiencing a dishwasher malfunction, call the Ajax appliance repair specialists at ES Appliance Repair.