Why Your Dishwasher Smells

(And How to Fix It for Good)

There’s nothing worse than opening your dishwasher expecting a clean load of dishes — and instead getting hit with a sour, swampy smell. If your dishwasher stinks, it’s doing the exact opposite of what it’s supposed to: clean.

Foul odors in dishwashers are common, especially in Florida’s humid climate, where moisture lingers longer and mold and bacteria thrive. Whether your unit smells like rotten eggs, mildew, or just a musty mix of old food and soap — here’s what’s really causing it, and how to eliminate it permanently.

What Causes Dishwashers to Smell Bad?

1. Food and Grease Buildup

Leftover food particles can collect in hidden spots inside your dishwasher — especially the filter, drain area, and spray arms. Over time, that buildup turns rancid, causing odors to rise every time you open the door.

2. Clogged or Dirty Filter

Most modern dishwashers (especially after 2010) use a manual-clean filter, which needs to be removed and rinsed regularly. If it’s clogged, water stagnates and food rots underneath the basket.

3. Standing Water in the Drain or Sump

If your dishwasher isn’t draining properly — even just a little — water can pool at the bottom and become a breeding ground for bacteria. In Florida homes with high water usage or older plumbing, this issue comes up frequently.

4. Moisture + Heat = Mold

Florida humidity makes things worse. A warm, damp environment inside your dishwasher encourages mold growth in the gasket, around the door seal, and in the spray arms, especially if you keep the door shut between cycles.

5. Improper Loading and Detergent Use

Stacking dishes too close together traps food and blocks water flow. Using too much detergent or the wrong type can also leave behind soap scum — which becomes a food source for bacteria.

Types of Smells and What They Mean

Smell Likely Cause
Rotten eggs (sulfur) Food decay, clogged filter, standing water
Musty or moldy Moisture in the door seal or drain line mold
Sewage or wet dog odor Blocked drain hose, garbage disposal backflow
Burnt or chemical smell Overheating components, burned food in heater area

Step-by-Step: How to Clean and Deodorize Your Dishwasher

Step 1: Clean the Filter

  1. Remove the bottom rack.

  2. Twist and lift out the filter (usually in the bottom center).

  3. Rinse under hot water with a soft brush — remove grease, food bits, and soap film.

  4. Soak in white vinegar if heavily stained.

Do this monthly — especially in Florida where water tends to sit longer in humid kitchens.

Step 2: Scrub the Spray Arms

  1. Remove upper and lower spray arms if your model allows.

  2. Use a toothpick or brush to unclog holes where food particles may be stuck.

  3. Rinse and reinstall.

Blocked spray arms = dirty water circulation = dirty, smelly dishes.

Step 3: Clean the Drain and Sump

  1. Wipe out the drain area at the bottom of the tub.

  2. Use a paper towel to pull out food, seeds, or broken glass around the pump inlet.

  3. If your dishwasher has standing water, you may need to unclog the drain hose or inspect the disposal inlet (see below).

Step 4: Run a Hot Cleaning Cycle

  1. Place a cup of white vinegar on the top rack.

  2. Run the hottest cycle with no dishes.

  3. After that, sprinkle baking soda on the floor of the tub.

  4. Run a short, hot rinse cycle.

This clears grease, neutralizes odors, and helps kill mildew.

Step 5: Wipe the Door Seal and Gasket

Use a damp cloth or toothbrush to clean the rubber door gasket and edges of the door. These areas trap grease, moisture, and mold — especially in Florida homes where air stays warm and damp even after the cycle ends.

Step 6: Check the Drain Hose and Garbage Disposal

In many kitchens, your dishwasher drains through the sink or garbage disposal. If the disposal is clogged or the hose is kinked, dirty water may back up into the machine.

Clean your disposal with ice, baking soda, and vinegar.
Make sure the drain hose has a high loop or air gap to prevent backflow.

How to Keep the Smell From Coming Back

  • ✅ Rinse heavy food off plates before loading

  • ✅ Run your dishwasher regularly — don’t let food sit for days

  • ✅ Leave the door slightly open after cycles to let moisture escape

  • ✅ Use high-quality detergent — and don’t overuse it

  • ✅ Clean the filter every 3–4 weeks (more often in busy households)

Bonus tip: Add a rinse aid to improve drying, especially helpful in humid areas like Orlando where moisture lingers in the air.

Still Smells After All That? It May Be a Mechanical Issue

If you’ve done all of the above and the odor returns within a few days, the problem could be deeper:

  • A clogged or moldy drain hose

  • A failing drain pump

  • A cracked or warped sump assembly

  • Burned food stuck on the heating element

These issues require disassembly and professional inspection — especially if the dishwasher isn’t draining fully or shows standing water after cycles.

We Can Fix That Stinky Dishwasher for Good

You shouldn’t have to hold your breath when opening your dishwasher. At ARS Repair Inc., we offer expert dishwasher cleaning, repair, and drainage diagnostics throughout Orlando and Central Florida. Whether it’s standing water, a hidden clog, or a part that needs replacing — we’ll handle it quickly and safely.

Smell something off? Schedule your dishwasher inspection today.