Why does my Dishwasher Smell?

Five Potential Reasons

It’s troubling when you open your dishwasher after a cleaning cycle and a foul odor emerges. You might ask yourself, why does my dishwasher smell so bad? How is that even possible? Once you know the answer to these questions, you can begin to address the problem.

Below, you’ll find five potential reasons for why your dishwasher smells bad, along with a few ideas on how to clean that dishwasher smell out.

1. A Clogged Food Trap

A common cause for a bad-smelling dishwasher is the presence of old, rotting food somewhere inside the unit. If your dishwasher smells, the first thing you should do is check the food trap located at the bottom of your tub. There’s a hole there that catches runoff from the cleaning cycle. While the dishwasher is dry, pull out the bottom dish rack and look to see if there’s old food inside the food trap’s basket.

If you don’t see food on the surface, pull out the basket if possible and dig farther into the opening to see if anything is there. Be careful when you do this—if you’ve ever had a glass break inside your dishwasher, there could be loose shards in the food trap.

In some cases, you may consider plunging out the opening in the food trap to unclog any waste that may have gathered. Regardless of how you do it, removing old food from your dishwasher should help reduce or eliminate a bad smell.

2. A Damaged Drain Hose

A drain hose works by emptying the dirty water and any small food particles into the disposal unit under your sink. If something is wrong with the drain hose, it could be the reason why your dishwasher smells.

If possible, pull your dishwasher away from the wall and look for any bends, kinks or other problems that would prevent the easy flow of material through the hosing. Try straightening the hose to make sure material can pass from one end to the other without a problem. If your drain hose is too damaged to straighten out, you may want to replace the part yourself or contact a professional to handle it.

3. A Poorly Placed Drain Hose

Even if your drain hose is not kinked or otherwise obstructed with food waste, it could still be the reason why your dishwasher smells. If your drain hose drops from the back of your unit and runs along the floor before moving upward towards the sink, gravity could be working against you.

If you have a drooping drain hose, try to find a way to reposition it. Ideally, your drain hose will run downwards from the dishwasher into the sink disposal, allowing gravity to do most of the work. If the dirty water and food waste don’t have to go “uphill” to the disposal, they’re less likely to get stuck and create a bad smell in the hose.

4. You’re Not Running It Enough

Even if you rinse your dishes before putting them in your dishwasher, tiny food particles can remain. If you tend to fill your dishwasher over the course of several days before running it when it’s full, that could be why your dishwasher smells bad. Bacteria can form and grow on dishes, feeding on the leftover food particles. When the bacteria breaks down during a cleaning cycle, they could produce the unpleasant odor you’re smelling in your dishwasher.

To remedy this problem, you may want to consider running your dishwasher more often. Even if it isn’t full, run it on the “light” cycle so you don’t use as much energy while washing fewer dishes.