Garbage Disposal Smells Really Bad: 3 Reasons Why & 9 Fixes


A garbage disposal offers convenience in eliminating soft food waste quickly and efficiently. Unfortunately, this appliance can emit an offensive odor.

Odors are commonly the result of rotten food, mold, or mildew. In serious cases, it could be a plumbing problem. You can eliminate odors from the disposal using home items such as vinegar, baking soda, dish detergent, citrus peels, ice cubes, salt, and more. Monthly maintenance and plumbing professionals, if necessary, can help your garbage disposal stay in good shape.

Let’s explore the causes of a smelly garbage disposal and what you can do to fix it in greater detail.

3 Reasons The Garbage Disposal Smells Really Bad

There are three main reasons why garbage disposals stink. In most cases, these foul odors can be easily remedied without calling in a professional.

1. Stuck Rotten Food

Most commonly, the cause of foul odors is the result of decaying food that is stuck in the garbage disposal.

Grease and grime can also cause odor.  When grinding food, cold water should be used to prevent fats and grease from melting and then solidifying into the mechanisms.

What To Do

When you are operating the disposal, you can use hot tap water for 30 seconds to loosen and rinse out any remaining and stuck debris or food particles after grinding. 

Keep in mind that if you have grease in the disposal, this will melt and then harden in your pipes, potentially causing more problems. 

Boiling water should be avoided with PVC pipes as this can damage and loosen joints. You can also turn off the electricity to the disposal and use tongs to remove any large and visible pieces.

If warm water does not do the trick, it is best to use the methods mentioned below to eliminate stuck food and deodorize the disposal.

2. Mildew or Mold

If the odor smells musty, stale, or earthly, then it may be mildew or mold that has built up in the sink or drain. 

Bleach can kill mold and mildew growth, but should not be used in your garbage disposal. It can cause damage to the blades (impellers) and pipes. 

Alternatively, you should use a cleaning solution as mentioned below.

3. Sewage Odors

If the offending odor smells like rotten eggs, then you likely have a sewage leak. At this point, open a window and cover the opening in the sink with a plate or bowl to reduce the odor. 

Then, call a professional plumber to find the leak and remedy it for you.

How to Fix A Smelly Garbage Disposal: 9 Ways

There are quick and easy DIY natural and non-toxic combinations, as well as commercial products that can be used to clean your garbage disposal. 

1. Commercial Garbage Disposal Cleaning Products

There are commercial products available for cleaning and deodorizing garbage disposals. 

Following package instructions and frequency of use.

However, you may opt for more budget-friendly options using supplies commonly found in your home first.

2. Baking Soda, Vinegar, Warm Water

Baking soda eliminates odors, and vinegar disinfects to remove odor-causing bacteria.

  1. Pour ½-cup of baking soda into the disposal.
  2. Warm 1-cup of vinegar to touch in the microwave or on the stovetop.
  3. Pour the vinegar into the disposal opening.
  4. Let the fizzy reaction sit for 10 to 60 minutes.
  5. Run warm tap water to rinse it clean.

3. Dish Detergent, Vinegar, Water

You can run a solution of dish detergent, vinegar, and water through it to loosen clogs, remove grease, and deodorize.

  1. Plug the drain of the disposal.
  2. Fill the sink with approximately 4 inches of cool water.
  3. Pour in 1-cup of vinegar and add two generous squirts of dish detergent.
  4. Use a kitchen spoon or your hands to swirl the water to create suds.
  5. Unplug the drain, and turn on the disposal while it drains the mixture.
  6. Run cool water to rinse the drain clean.

Alternatively, you can use dish detergent and baking soda. Make a thick mixture of the two to form a paste. Scoop the paste into the disposal, and run the disposal clean with running cold tap water.

4. Mouthwash

Mouthwashes are designed to inhibit the growth of odor-causing bacteria. When choosing a mouthwash to use, refer to the label for one that states it is antibacterial, antiseptic, or antimicrobial.

  1. Pour 1-cup of mouthwash into the drain.
  2. Let it sit for 10 minutes.
  3. Run the disposal, rinsing it clean with cold water.

5. Citrus 

Citrus peels or citrus-scented dish detergent can freshen up a stinky disposal drain. Alternatively, a few drops of citrus essential oils mixed in with a few tablespoons of dish detergent will work as well.

Squirt the citrus-scented dish detergent into the disposal and let it sit for 10 minutes. Then, rinse it clean with warm tap water.

If you opt for lemon, lime, or orange citrus peels, you must make sure that you do not cause damage to your garbage disposal’s blades. The peels can help to dislodge other stuck particles and grease while eliminating odor.  

To use citrus peels:

  1. Do not use large amounts or pieces of peel. Cut the peels up into quarter-sized or smaller pieces to avoid jamming. 
  2. Run the disposal to grind the citrus peels with cold water. 
  3. Once the disposal is clean and clear, run warm tap water to rinse away any remaining debris.

6. Ice Cubes And Salt

You can eliminate stuck debris in the disposal’s blades by running a few ice cubes with tap water at the coldest setting through it.  

Additionally, you can use salt with the ice cubes. Salt adds more friction to help dislodge any debris. 

  1. Place your ice cubes in the disposal and sprinkle about ½-cup salt on top of them. 
  2. Run the disposal with cold water to grind the combination through. 
  3. Run the cold water for an additional two minutes after the ice is gone.

If an odor remains, follow up with any of the other mentioned strategies.

7. Clean The Splash Guard

The splash guard may have rotten food or mildew underneath it. Grease and grime can get stuck in the crevices.

Do the following:

  1. Make sure that the power and switch are off to your garbage disposal. 
  2. Use tongs to grab the gasket or splash guard at the top of the disposal. Never use your hands inside this area to avoid injury.
  3. Soak it in a vinegar and baking soda mixture or dish detergent and warm water for 10 minutes. 
  4. Scrub the mixture onto it, paying attention to the crevices. 
  5. Rinse clean. 
    1. If the odor remains, consider replacing the rubber part.

8. Borax

Borax is a safer non-beach alternative for cleaning and deodorizing your garbage disposal. 

Pour ½-cup of borax into the garbage disposal. Then, run the disposal with cold water for at least two minutes. 

Follow the product’s safety label for storage and use.

9. Scouring Powder

Opt for a non-bleach scouring powder that is safe for use with plumbing and the material composition of your sink. A scouring powder can help to eliminate debris and deodorize the unit.

  1. Mix ½-cup of powder and ⅛-cup of cold water and pour into the disposal. 
  2. Let it sit for 15 minutes. 
  3. Run the garbage disposal with cold water to rinse it clean.

Prevention of Odors

To reduce the chance of bad smells, and to give your disposal many years of operation, you should consider the following strategies.

Avoid Using Certain Items In The Disposal

Garbage disposals are meant to grind up soft and small food waste with cold running tap water. Refer to your user manual on what is and is not acceptable. 

The following are some examples of food that can become lodged in or clog up your disposal. 

Do not put these items in your garbage disposal:

  • Coffee grounds
  • Eggshells
  • Starchy foods, such as potatoes
  • Banana peels
  • Nuts
  • Bones
  • Meat
  • Non-food items
  • Bleach
  • Hot water when grinding

When grinding acceptable foods in the disposal, always use cold water.

Maintenance

You should clean your garbage disposal once or twice a month. You can use any of the above-mentioned methods for eliminating odors which also work for regular cleaning maintenance.

If you get glass or a jammed disposal that will not run properly, take it apart to clean it. The water and electricity sources must be turned off before attempting this task.

This video demonstrates how to fix a garbage disposal:

If in doubt, contact a plumbing professional.

Conclusion 

Garbage disposals are a common investment that homeowners use for convenience and to eliminate food waste.

If the disposal starts to smell really bad, it can be quickly eliminated in most cases. This involves removing any food particles, mold, or mildew by running a cleaning solution or strategy through the disposal.

Most of the time, this will eliminate the odor and you can resume using the garbage disposal. If not, then it may be time for a plumbing professional.

Lisa Burlison

Lisa is a freelance blogger, literacy specialist, teacher, and self-published author with a vast DIY experience. When she’s not writing for PlumbJoe, Lisa enjoys testing homemade cleaners and doing repairs around her home. Her other hobbies include birding and bicycling.

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