Why Does my Sink Fill up When Dishwasher Runs? (3 Reasons Why)

Originally Created on: May 11, 2022 @ 1:01 pm

Why does my sink fill up when dishwasher runs? A sink is a very significant kitchen appliance such that it is regarded as the heart of the kitchen. However, there are times when the sink clogs, which has become a concern for many, especially when they are running their dishwasher.

The last thing everybody wants is to experience sink problems when doing the dishes, particularly with the dishwasher.

However, such problems occur due to various causes concerning the sink’s plumbing section, which will need fixing sooner than later so you can jump right back into your routine.

Since the problem can arise due to various reasons, the answer to such a question can never be straightforward, and you will need to assess to come to a conclusion, so keep reading.

Why Does my Sink Fill up When Dishwasher Runs?

A clogged sink, blocked air gap or blockage in the garbage disposal area are the three most common reasons why your sink may fill up when the dishwasher is running.

Some of these problems require pros to solve, while some you can solve yourself. Here are the main reasons why your sink fills up when the dishwasher runs and how to approach each of them.

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Reasons Why Sink Fills Up When Dishwasher is Running

1) Clogged Sink

Your sink might clog even if you rarely allow large chunks like corn silk or asparagus and starch items like rice, carrots, potatoes, and bread to dispose off through the sink. If you put fat or grease in the drain, they stick to the walls and narrow the pipe opening gradually, leading to blockage after a while. Therefore, since preventing this problem is easier than fixing it, it would be better to be more careful with what you allow down the drain.

2) Block in the Air Gap

Some sinks have air gaps installed next to the faucet to prevent backflow. However, after using the sink for a long time, the air gap can get clogged, making your dishwasher unable to drain when running and filling the sink in the process. Therefore, air gap blockage could be a problem if your sink has an air gap installed and it fills when you run the dishwasher.

3) Blockage in Garbage Disposal or Dishwasher

Like the sink, a dishwasher or garbage disposal might clog due to starch particles, grease, or fat deposition on the sides, narrowing the pipes and making the dishwasher back up the sink. These problems can be easily avoided by not allowing greasy, fatty, sticky, or deposition of large chunks in the pipes.

So, how do you solve it if either of these causes makes your sink fill when the dishwasher runs?

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How do you Fix a Dishwasher Backed up into the Sink?

The causes mentioned above are the common issues leading to your dishwasher backing up into the sink. So, how do you fix a dishwasher backed up into the sink?

Sometimes you might feel uncomfortable fixing this problem yourself, and you will need to summon a profession to do it professionally. However, it might be easy to fix it yourself, and if you decide to, here is the way to do it.

If you decide to solve the problem yourself, you have to put your safety first. Therefore, turn off the power to the disposal and peer into the drain using a flashlight to spot what is clogging the disposal. This will make it easier for you to take the next step. After spotting the cause of the clog, wear gloves or use tongs to remove the clogging waste for you to reach the constituents underneath the sink to crank it manually from the bottom. 

You can now run hot water through the pipes to clean the residues and melt the fat or grease present on the sides. 

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Can I Run My Dishwasher if My Sink is Clogged?

A dishwasher works hand in hand with a sink, and if the sink is clogged, you will need to find a solution before embarking on your chores. Therefore, you cannot run your dishwasher if your sink is clogged. Here is why.

A dishwasher solely depends on the sink’s disposal to get rid of the dirty water and food particles from the dishes. This means that if the sink is clogged, the dishwasher’s waste will have no way out, making it extremely hard for the machine to run. Moreover, it is recommended you first check whether the sink is clean before you start running the dishwasher.  

Therefore, you can never run your dishwasher if your sink is clogged since the waste from the dishes will have no way out of the dishwasher. You will first of all need to unclog the sink. Ensure the water is running smoothly through the sink for you to run the dishwasher. Therefore, the answer to the question, (can I run my dishwasher if my sink is clogged?) is no since the dishwasher requires the sink while in good condition for it to function.

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Conclusion

The kitchen sink is the heart of the kitchen, and if it fails to function, the kitchen will be a mess. Nowadays, almost every kitchen has a dishwasher to make the work easier, but sometimes when you run the dishwasher, you might notice your sink fills up. This raises the question, why does my sink fill up when the dishwasher runs?

You should check out for a clogged sink, blocked air gap or blockage in dishwasher or garbage disposal as some of the possible reasons why your sink is filling up when the dishwasher is running.

This problem can be easily solved by calling a professional plumber or doing it yourself. However, all these causes can be prevented by not allowing starch foods, grease, or fat in the disposal pipe. Deposition of starch foods like rice, bread, potatoes, and carrots can block the pipe while fat and grease stick on it, narrowing it gradually and blocking it eventually.