Why Does My Sink Back Up When I Run the Dishwasher?

Posted On: March 01, 2016

Water running down the drain of a kitchen sink

Having a dishwasher is very convenient, as washing dishes by hand is never much fun. However, there are times when using a dishwasher can be a hassle too. Like when you come home to find your sink full of dirty water. This can be an inconvenience and quite frankly, gross.

The sink backing up when running a dishwasher is a very common problem that a lot of the time can be fixed with just a simple plumbing repair.

the 4 most common reasons your Dishwasher is backing up into the sink

Here are a few common reasons your dishwasher may be backing up into your sink.

1. Jammed/Slow Garbage Disposal

Check to make sure your drain plug isn’t covering the garbage disposal. If the drain plug is covering the garbage disposal it can result in water not properly draining from your dishwasher or sink. This is a simple fix. Take the drain plug out and the problem should be solved.

Most likely, your fix isn’t going to be quite that simple. Let’s move on to the next culprit, a slow garbage disposal. An older way of connecting dishwasher drains was to use a small drain inlet on the side of a garbage disposal. This way works fine if there is no debris in the way so the water can drain quickly. However, in this case if the garbage disposal is clogged, even partially, it can cause the dishwasher to back up into the garbage disposal (and then the sink). The easiest fix in this case is to clean your garbage disposal.

2. Clogged Sink

If the garbage disposal isn’t to blame it could be that you have a clogged sink. Safe drain cleaners or a drain snake may help you clear the drain. The professional plumbers at Genz-Ryan are always here to help if you’re having trouble.

3. Blocked Kitchen Sink Air Gap

Some kitchen sinks have an air gap installed with them. If the air gap is clogged, this will stop your dishwasher from draining properly giving you a sink full of water. Clean your air gap by removing the top cover and then unscrew the inner protective cap to see if debris is easily removable.

4. Dishwasher Obstruction

If you open the dishwasher and see standing water sitting at the bottom of it, you’ll know the dishwasher is not draining properly. Check to see if food or other debris is covering the drain in the back of your dishwasher. In addition, check the drain hose on the dishwasher to see if there is a kink.

5. Dirty dishwasher filter

Food particles like seeds or wet paper can get caught in the filter and prevent water from draining properly. It’s important to clean your filter regularly to prevent this from happening.

Contact genz-ryan heating, cooling, plumbing and electrical for plumbing fixture repair

Even minor, annoying plumbing problems can become extremely damaging to your plumbing system. The professional plumbers at Genz-Ryan Heating, Cooling, Plumbing & Electrical are ready to help you with any job, big or small.

We’re a family-owned and -operated business dedicated to delivering exceptional service to our customers and helping our community. Our plumbing professionals are courteous and knowledgeable, providing superior workmanship and uncompromising customer satisfaction.

If these solutions aren’t doing the trick or you’re not comfortable attempting them, the best thing you can do is contact a professional plumber to diagnose the issue. Don’t wait, give us a call at (612) 223-6158 or contact us online today to request plumbing services in the Twin Cities!