If you are looking for a one-word answer to this question, it would be a YES. Whether directly or indirectly, the garbage disposal is often linked with a smelly dishwasher. However, there are some technical details that you must know to determine the actual problem (and solve it).
How Can a Garbage Disposal Affect the Dishwasher?
As the dishwasher is connected to garbage disposal, any problem with the disposal will affect the drainage of your dishwasher. This is the reason why a faulty/broken garbage disposal can result in a smelly dishwasher.
It is important to have proper knowledge about the working of the garbage disposal to understand this relationship. Basically, there are two pipes in your sink’s drain. One of them is the drainage pipe that stores the food waste from the garbage disposal. It has nothing to do with your dishwasher.
An issue with the Air Break
The second pipe connects the dishwasher to the garbage disposal for water discharge. There is an air break in this pipe to ensure that the dirty water is not returning to the dishwasher. In case there are some issues with this air break, this water goes back to the dishwasher. This generally happens when your garbage disposal has broken down.
In this case, your dishwasher will produce a foul odor.
Dishwasher Drain Hose is Lower than the Garbage Disposal Opening
This issue is much more common than the first one. In this scenario, the water from the garbage disposal drains into the dishwasher. This dirty water will create a bad smell around your sink. In extreme cases, bacteria will start to accumulate in the drain hose that can have serious health implications. Therefore, you should be careful with the maintenance of these appliances.
The most common cause of this problem is the improper installation of the dishwasher hose. Ideally, the drain hose must be attached to your kitchen counter so that it doesn’t go that low.
Can a Garbage Disposal Backup into the Dishwasher?
YES, it is possible for a garbage disposal to backup into the dishwasher.
There is no doubt that the dishwasher is a really convenient appliance, especially after a long day at work. However, it can become a really painful experience when using a dishwasher fills your sink with dirty water.
There are a number of reasons for this gross inconvenience. The backing up of your garbage disposal into the dishwasher is only one of them.
Jammed Garbage Disposal
If the drain plug is covering the opening of your garbage disposal, the water from the dishwasher won’t drain properly. This will push the water back into the dishwasher and ultimately the sink. Such a problem is usually encountered when a new garbage disposal is installed. In order to solve this problem, all you need to do is to remove the drain plug.
Slow Garbage Disposal
Traditionally, a small drain inlet was used to connect the dishwasher with garbage disposal. This is an effective method for draining water until there is some solid waste in it. These food particles will clog the garbage disposal and the flow of water will be affected. This will cause the water to back up into the sink through the dishwasher.
My Sink Fills Up When I Run the Dishwasher
Other than the garbage disposal, there are some reasons that can cause your dishwasher to malfunction. A couple of them are explained below.
Sometimes, the drain of the dishwasher gets choked by food particles or any other debris. In order to check that, you will need to see if there is any water at the bottom of the appliance. The presence of water indicates that something is not right with the dishwasher.
You will need to clean the drain of the dishwasher to solve this problem. Other than that, you can also check the drain hose to make sure that everything is in order.
Clogged Air Gap
Some people install air gaps as a backflow prevention device for their dishwashers. Although there are some benefits of this appliance, a blockage in it can prevent the dishwasher from draining. The most obvious check for a clogged air gap is that water starts flowing from this device.
Once you have deduced that there is a clog in the air gap, start by removing its top cover. Now, unscrew the protective cap and look inside for any visible debris. If the blocking material is visible, remove it and re-assemble the device. Otherwise, you may need a 12-inch bottle brush to clean the air gap.
Note: If none of the above-mentioned solutions solve your problem, it’s best to get some professional help by contacting a plumber.