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Kitchen Sink Won’t Drain But Isn’t Clogged – What’s Wrong?

 A lot of waste goes down the sink, since it's one of the most used fixtures in the kitchen. But did you know this might be why the sink isn't draining well? Before calling a plumber, we researched what can cause the kitchen not to drain, even if there isn't a clog.
 
Food waste and oil are the reasons your kitchen sink won't drain. If not removed, these can build-up in the pipes. Here are some ways to loosen food waste and oil, so your sink will drain water properly: 
  • Hot Water
  • Sink Plunger
  • A Mix of Baking Soda and Vinegar 
  • Plumber's Snake

These are DIY solutions that one can do without the help of a plumber. Read on to learn how to use these home remedies and other tips on kitchen sink maintenance.

Disclosure: We may get commissions for purchases made through links in this post.

a clean stainless silver sink, Kitchen Sink Won't Drain But Isn't Clogged - What's Wrong?

How to Fix Kitchen Sink if Not Draining Well

Pots and pans used for cooking will have food leftovers and oil. You tend to rinse and pour these into the drain. However, big pieces of meat or vegetable can get stuck in the pipe.

Oil solidifies when it comes in contact with cold water and adheres to the pipes. Water will pass through slowly because of these blockages.

There are many ways to solve this problem. Some may be temporary fixes. But it allows you to use your sink until a plumber is available to check the drainage issue.

Plumber installs a sink with a faucet to water pipe in kitchen

1. Hot Water

The immediate remedy for the sink to let water flow out of the drain is to pour hot water. This will melt grease and loosen food waste. This method may need to be repeated a few times to make sure the water is draining well. 

Remove as much water stuck in the sink before pouring hot water. Also, note the material of your pipe. For metal pipes, use boiling water. But, for PVC pipes, pour hot and not boiling water to prevent damaging them.

For kitchen sink maintenance, you may also pour hot water at the end of every washing. Doing this will prevent grease and dirt continue to build up. 

2. Sink plunger

Loosen large chunks of food stuck in the pipe with the use of a sink plunger. This will cause pressure and remove the blockage to allow water to pass through.
 
 
Before using the plunger, pour hot water on the sink to loosen the blockage. Then, fit the plunger snugly over the drain. Firmly pump the plunger a few times. Do this several times to release the clog.

3. A Mix of Baking Soda and Vinegar 

Both baking soda and vinegar are versatile home cleaners and can be used to de-clog your kitchen pipes. When these two kitchen items react, they will loosen the grime and grease build-up in the pipes.  
 
 
The first thing to do in this declogging process is to pour hot water into the drain. Next, place at least 1 cup of baking soda. Immediately pour the same amount of vinegar.
 
Don't be surprised to see bubbles come out of your drain, as this is a chemical reaction. Let this mixture sit for about 10 minutes. Pour the hot water again and see if the water is draining faster. If not, you may have to do this method several times.

4. Plumber's Snake

The plumber's snake or a coiled spiral snake is a tool that can clean the pipes from grime buildup.
 
 
Uncoil the wire and push it through the sink drain. When there is resistance, it means there's a clog. Put extra effort into spinning the plumber snake.
 
Pull out and clean it. Do this several times. Then, pour water to see if it is draining well. Depending on the length of this tool, it may not remove dirt down the pipe.
 
What do you do then if the kitchen sink is still not draining well after trying any or all of the cleaning options? It is time to call for a professional cleaning service. 

When to Call For Help?

Woman calling for a plumber to repair her sink

Pipes and air vents can be the cause why your kitchen sink is not draining well. To check and fix these, you will need help from an expert. 

P- trap 

A kitchen sink is attached to pipes where water flows out to the main drainage. Check out the sink cabinet, here you will see a u-shaped pipe.

This is the P-trap where water stays to prevent gasses to go inside the home. However, this is also the section that is prone to waste build-up and causes water backflow.

Cleaning the P-trap is a job for a plumber. To remove the P-trap is messy with all the water and waste stuck inside. Also, doing it on your own can cause more damage to the pipe if you are inexperienced. 

Air vent

The flow of water in the pipes creates a vacuum. If there is no air to push the vacuum created, water will not flow through the pipes. The plumbing air vent or vent stack lets air into the pipes as well as removes gasses and odor stuck in the pipe. 

The vent stack is on the roof. However, it is exposed to external elements like leaves, dust, and other debris that can block the opening of the vent. 

You will need the help of a cleaning professional to remove the blockage. If not, air cannot enter the pipes, causing water to be stagnant. Eventually, the pipes cannot contain the water and it will go back up into the drain. 

Things You Should Not Throw in the Kitchen Sink

Flat lay view of mix of vegetables waste in home kitchen sink.

You might be surprised that small items thrown in the kitchen sink can cause water to drain poorly in your kitchen pipes. These items don't flow out. Instead, they cause a build-up in the pipes.

Food Scraps

You might throw in the sink food scraps from the plates. These could be small pieces of meat or vegetables that can easily go down the drain.
 
However, these scraps can stay in the P-trap and can block the passage of water. So, be conscious of scraping food from your dirty dishes to the garbage bin before washing them. 

Grease and Oil

Never pour bacon grease or oil from cooking french fries into the kitchen sink. The fat from cooking will harden and build up in the pipes. This kitchen waste will cause the pipe passageway to get smaller and not allow water to easily pass through the pipes.
 
There are safe and economical ways to dispose of used oil. Pour it into a tightly sealed container and let it solidify before throwing away.
 
You may reuse oil as well by straining it. Use a stainless oil strainer to remove burnt food. Keep it in the refrigerator, so it will not spoil. Doing this keeps the oil good for cooking for 30 days.
 

Ties, Tapes, and Stickers

When washing vegetables and fruits, be mindful of ties, tapes, and stickers that come with these food items. Vegetables are put together with a tie or tape. Fruits usually have stickers to show the brand.
 
These tiny items can be removed easily before washing the food items. However, they do not break down with water going down the drain. It can stay in the pipes and add to the build-up of dirt and grease. Thus, these should go to the garbage can and not the sink. 

Can Garbage Disposal Cause the Sink Not to Drain Well?

The kitchen sink is clogged and the water does not run down the drain

Kitchen sinks may come with a garbage disposal unit. This will grind food waste into tiny pieces. Thus,  making it easy to flush out of the kitchen pipes.

However, food waste like bones, corn husks, or potato peels are hard to grind. Also, putting too much food waste in the unit will not make it work properly.

Big chunks of food waste will not pass through easily and can cause blockage in the pipes. To avoid this, throw only the correct food waste in your garbage disposal unit. 

What is a Drain Guard?

A sink drain guard is a kitchen tool to catch food waste and dirt in your sink. This is also useful when your sink does not have a garbage disposal unit. Using it in your sink prevents large pieces of food waste from getting stuck in the drain.  

Having this kitchen sink strainer will protect your sink from clogging in the long run. This will also save you money from calling the plumber to unclog and fix the pipes. 

Check this kitchen sink strainer on Amazon

To Wrap Up

a clean stainless silver sink

At this point, you know what causes your kitchen sink to drain poorly. Don't only use ways to remove food, oil, and other waste materials when a problem comes up. Continue to use DIY solutions to ensure your kitchen drainage will not have any blockages.

For other kitchen concerns, check these out:

How To Match Your Kitchen Cabinets

How To Hide Kitchen Vent Pipe