Recommendations are independently chosen by Reviewed’s editors. Purchases you make through our links may earn us a commission.

You love your dishwasher. It frees up your time, so you can binge Netflix after dinner instead of standing by the sink up to your elbows in greasy dishwater. Besides, dishwashers do a better job washing dishes than you can possibly do by hand. But if you really want clean dishes, you have to stop making these common mistakes.

1. Pre-washing

South Wales Argus: It's pointless to pre-wash dishes before putting them in the dishwasher. Stop doing this. It's a waste of time. Credit: Getty Images / RyanJLaneIt's pointless to pre-wash dishes before putting them in the dishwasher. Stop doing this. It's a waste of time. Credit: Getty Images / RyanJLane Pre-washing your dishes is a pointless waste of time and water. Plus, you’ll get better results if you leave some dirt for the detergent to work on. So, don’t wash before you wash. Even the stickiest, dirtiest plates can come out clean if you just scrape them first.

2. Blocking the spray

South Wales Argus: The cardinal sin of dishwashing is blocking the water spray. If you do that, there's no point in running the dishwasher, because your dishes won't get clean. Credit: Reviewed / Jonathan ChanThe cardinal sin of dishwashing is blocking the water spray. If you do that, there's no point in running the dishwasher, because your dishes won't get clean. Credit: Reviewed / Jonathan Chan

The cardinal rule of loading the dishwasher—don’t block the water jets. If you put a big platter or baking sheet in the way of the spray arm, the rest of the dishes will not get clean. Remember, the big items go on the sides. If you’ve got a deep roasting pan to clean, remove the cutlery basket, and see if you can fit the pan into the space. You can wash the cutlery in the next load.

3. Letting spoons “spoon”

South Wales Argus: What your spoons do on their own time is up to them. What they do in your dishwasher is up to you. Credit: Reviewed / Jonathan ChanWhat your spoons do on their own time is up to them. What they do in your dishwasher is up to you. Credit: Reviewed / Jonathan Chan

Speaking of cutlery, do not let it nestle together in the basket. If the spray can't get to the surfaces, you'll be unloading dirty forks and spoons. If you have a basket with a grid, use the slots to separate each piece. If it’s an open basket, load it so that some utensils point up, and some points down. (Knives are exempt—they always point down.) Use the third rack if you have one—it keeps cutlery from getting too close.

4. Overloading

South Wales Argus: This dishwasher looks like it's already full, but the owner can't resist adding another bowl. Don't do this if you want your dishes to get clean. Credit: Getty Images / CasarsaGuruThis dishwasher looks like it's already full, but the owner can't resist adding another bowl. Don't do this if you want your dishes to get clean. Credit: Getty Images / CasarsaGuru

Overcrowding the dishwasher makes it hard for it to get your dishes clean. The water has to be able to reach every surface. I know how it feels to see those last few filthy dishes in the sink, and really wishing there was room for them. But it's better to wash the last couple of plates by hand or save them for the next load.

5. Skipping rinse aid

South Wales Argus: If your glasses have water spots, just use rinse aid the next time. Credit: ReviewedIf your glasses have water spots, just use rinse aid the next time. Credit: Reviewed

Maybe you would remember to pour in rinse aid if it were called “dry aid.” Modern dishwashers dry using hot water, not hot air. Rinse Aid helps water sheet off the tub and the dishes, so it goes down the drain. Less water ends up on your dishes. If you're seeing spots on your glasses, you're probably not using rinse aid.

6. Neglecting to clean the filter

South Wales Argus: Reach in, remove the filter, and wash it. You can even scrub food off it with a soft toothbrush, but be gentle. While you've got your head in the dishwasher, use a skewer or toothpick to clean debris out of the water jets. Credit: ReviewedReach in, remove the filter, and wash it. You can even scrub food off it with a soft toothbrush, but be gentle. While you've got your head in the dishwasher, use a skewer or toothpick to clean debris out of the water jets. Credit: Reviewed

If you don’t clean the filter, from time to time, your “clean” dishes can feel gritty and end up covered with tiny food particles. So, periodically reach under the spray arm and remove the filter. Soak it in warm, soapy water for a few minutes, go over it with a toothbrush (not your current one), then rinse it under the tap. Plug it back into the dishwasher, and while you’re down there, use a skewer to push out any gunk that’s clogging up the jets on the spray arm.

7. Allowing food to dry on the plates

South Wales Argus: It's hard for your dishwasher to remove dried-on food—and spinach is the worst. If you can't run a full normal cycle right away, at least start a rinse cycle. Credit: Reviewed / Jonathan ChanIt's hard for your dishwasher to remove dried-on food—and spinach is the worst. If you can't run a full normal cycle right away, at least start a rinse cycle. Credit: Reviewed / Jonathan Chan

It's hard for your dishwasher to remove dried-on food—and spinach is the worst. If you can't run a full normal cycle right away, at least start a rinse cycle.

If you have to walk away without starting a full cycle use the rinse cycle to hold down disgusting odours and keep food from drying on the plates. You’ll be glad you did.

8. Loading things in that aren't dishwasher safe

South Wales Argus: Some things should never go in the dishwasher. Don't even think of loading cast iron pans, wooden spoons, or anything that isn't labelled as dishwasher safe. Credit: Getty Images / K_ThalhoferSome things should never go in the dishwasher. Don't even think of loading cast iron pans, wooden spoons, or anything that isn't labelled as dishwasher safe. Credit: Getty Images / K_Thalhofer

You can wash a few things that aren’t dishes in your machine. I've heard of everything from hubcaps to hairbrushes! But some things you should never consider washing in the dishwasher are cast iron or aluminium pans, wooden spoons and cutting boards, your good kitchen knives, or plastic takeaway containers. To be on the safe side, avoid putting in anything that isn't labelled “dishwasher safe.”

9. Using the same cycles all the time.

South Wales Argus: If you always use the Normal cycle or leave it on Auto, you and your dishes are missing out on the dishwasher's versatility. Credit: Reviewed.com / Jonathan ChanIf you always use the Normal cycle or leave it on Auto, you and your dishes are missing out on the dishwasher's versatility. Credit: Reviewed.com / Jonathan Chan

Breaking News—your dishwasher has other cycles besides Normal. Depending on how tough the food stains are, you should consider using the heavy cycle, especially for crusty pots and pans. The delicate cycle works well for glassware. And don't shy away from the quick cycle when you've got a lot of not-too-dirty dishes to wash. It might not clean every bit as well as a normal cycle, but one hour later, when the cycle is done, you may not care.

10. Not reading the user manual

South Wales Argus: Find your dishwasher's user manual, and use it. Yeah, it's not a compelling read, but it will show you the best ways to load. And if anything ever goes wrong, the manual will help you troubleshoot. Credit: Reviewed / Jonathan Chan Find your dishwasher's user manual, and use it. Yeah, it's not a compelling read, but it will show you the best ways to load. And if anything ever goes wrong, the manual will help you troubleshoot. Credit: Reviewed / Jonathan Chan

You probably haven’t seen the manual since the day your dishwasher was delivered. Or maybe you never got one when you moved into the place. But look for it online right now–it’s filled with recommendations on the best way to load dishes for your model, and offers troubleshooting tips for when something goes wrong. It will never be a best-seller, but reading the user manual can save you a lot of aggravation.

The product experts at Reviewed have all your shopping needs covered. Follow Reviewed on Facebook, Twitter, and Instagram for the latest deals, product reviews, and more.