Like most appliances, garbage disposals can go on strike every now and again. Maybe they simply hum instead of grinding food waste or fail to drain correctly – whatever it is, it’s problematic. Since most kitchen sinks drain through their garbage disposals, including double sinks, the non-draining garbage disposal is problematic.
So, if your kitchen sink is filling with water and your garbage disposal remains unbothered by the issue, you’ll need to lend a helping hand. There are a few potential fixes you can try, which we’ll review in this article.
Why Is My Garbage Disposal Unit Pushing Water Back Up?
When your garbage disposal starts pushing water back into the sink, there’s usually one culprit: a blockage. The blockage can be a few different things, like a foreign object blocking the drain hole or a clump of food particles lodged in the drain pipe.
However, there are some cases when a bit of water push-back is normal. In many cases, you’ll notice gunk burbling out of the drain after cleaning it with ice. Grime and gunk will rise out of the drain before swirling back down as the system works through the ice, leaving a cleaner canister in its wake.
What Can You Put Down A Garbage Disposal To Unclog It?
While you can use various commercial chemicals to unclog a garbage disposal, we recommend against it. There are dozens of chemical cocktails available online and in stores, each designed to tackle tough clogs in drainage systems. Although these chemicals are usually highly effective, it’s generally better not to use them, as they can do more damage than good.
Generally, the best way to address a clogged garbage disposal is by looking for the root cause, whether it’s stuck food or a foreign object.
How Do You Unclog A Garbage Disposal?
The process of unclogging a garbage disposal is usually relatively straightforward. Of course, some problems are more complex than others, but before you call a plumber, it doesn’t hurt to try the following methods.
Look For Foreign Objects
Before you start troubleshooting the issue, it doesn’t hurt to check for miscellaneous objects lodged in the disposal canister. Sometimes, random objects will end up in the canister, and although their journey into the canister is a mystery, there’s no doubting their presence.
Objects like keys, kid’s toys, and silverware can block the drainage hole, allowing food particles to build up over them until there’s a blockage. Here’s what you’ll need to check:
- Pliers or kitchen tongs
- Cup and bucket
Start by turning off the power to the unit. Shut off the power at the wall switch or circuit box (if necessary) and unplug the unit. Once the power is off, scoop the excess water out of the sink using a cup and a bucket.
Next, peek inside the canister using the flashlight to see inside. You’ll probably need to push the baffle (usually the black rubber piece around your kitchen sink drain) to the side to get a good look.
If you see something in the bottom of the canister, reach in and grab it using a pair of tongs or pliers. Never reach into the canister with your hands, even if the power is off. Remove the object and restore power to the unit.
Check for proper drainage and function.
Use A Sink Plunger
If you don’t see anything hanging out in the bottom of the disposal’s canister, the blockage might be further beyond the canister in the drain tube. So, to dislodge the clog, employ the assistance of a sink plunger. These plungers differ from toilet plungers because they are designed specifically for sinks.
Here’s what you’ll need:
- Sink plunger
Fit the cup of the plunger over the mouth of the drain. Ensure the cup fits entirely over the drain, as it needs to cover it to create suction. Once the plunger is in place, fill the sink with just enough water to cover the plunger cup. Plunge vigorously 4-5 times, then remove the plunger.
If the water swirls down the drain, you’re good to go. However, if nothing happens, you might need to try again. Try the method a few more times, but if nothing happens after a few tries, move to the following method.
Manually Spin The Blades
Sometimes, a bit of gunk is caught around the blades (like a banana peel), effectively preventing the unit from crushing food bits. Since the unit can’t do its job, larger food particles may pile up, causing the disposal to become blocked and push water into the sink.
To free the blades, you can manually spin them using a hex wrench and the tiny hole at the canister’s base.
Here’s what you’ll need:
- Allen wrench (aka hex wrench or key)
Head down underneath your sink and clear out the cabinet. You’ll need to access the bottom of the garbage disposal, so you’ll need a bit of room to move around. Once you clear out the cabinet, fit the Allen wrench into the hole at the base of the canister.
Gently turn the blades clockwise until you feel them meet resistance, then spin them back the other way until you feel resistance. Work the blades back and forth, slowly moving through the gunk that is freezing them in place. Once the blades spin freely in both directions, remove the Allen wrench.
Head up above the sink and turn the garbage disposal on, ensuring you run cool water if there isn’t standing water in the sink. If the garbage disposal works through the remaining food scraps in the container and drains normally, you’re good to go!
Remove The P-Trap
Sometimes, plunging the sink and wiggling the blades won’t do the trick, as the clog is hanging out further beyond the garbage disposal itself. Instead, it might reside in the drain tubes, closer to the P-trap. The P-trap is the U-shaped pipe underneath your sink that holds air and prevents smelly sewer gases from exiting your sink drain.
Here’s what you’ll need:
- Screwdriver (as needed)
- Plumbing auger
Place the bucket underneath the P-trap, as there will be water in there. Make sure you choose a large enough bucket to catch the water in the sink, too, as it’ll drain out when you remove the trap (if the blockage is in this section of plumbing).
If the trap is secured by screws, unthread them. Some P-traps are connected with a large plastic nut, so if that’s the case, unthread the nut.
Once you loosen the trap, gently wiggle it off of the plumbing assembly. Allow the water to drain into the bucket below. Check the P-trap for blockages and remove them as necessary. If you don’t see any blockages in the P-trap, check the remaining plumbing.
Feed a plumbing auger into each end of the piping, feeling for blockages that might be causing the issue. If you feel resistance, rotate the auger’s handle to dislodge the blockage and draw it out of the pipe.
Once the blockage is removed, reattach the P-trap and secure it to the plumbing. Once the trap is secure, turn the water on and check the garbage disposal for proper drainage and function. Watch for leaks around the P-trap and address them if you find a leaky area.
Use Baking Soda And Vinegar
This solution won’t work for disposals with an excessive amount of water backed up in the sink, but it can be an excellent drain cleaner for partially-cleared clogs. For example, maybe you tried one of the above methods, and although it worked, the system might still drain a bit slowly.
If that’s the case, finish it off with a baking soda and vinegar treatment. The reaction helps dislodge any stubborn remnants of the clog, ensuring the canister and drain are blockage-free. In addition, the mixture helps clean and deodorize the system, effectively removing nasty smells.
Here’s what you’ll need:
- Baking soda
- Hot water
Pour approximately one cup of baking soda into the garbage disposal canister, then immediately follow up with one cup of distilled white vinegar. As the two come into contact with each other and mix, they’ll start bubbling and foaming, creating a reaction reminiscent of the sixth-grade science fair (volcano project, anyone?).
Let the mixture bubble and fizz for a while, giving it at least 20 minutes to work. Once the reaction slows, run hot water down the sink to flush out residual gunk. And just like that, you’ll have a fresher, cleaner garbage disposal!
Call A Professional Plumber
If all else fails, call a plumber. Sometimes, the blockage is further in the drain pipes than you can reach or find, so you’ll need to enlist the help of a plumber. Or, if you can’t pinpoint the issue and your sink remains partially filled with grubby water, a plumber can help isolate the problem and get everything running smoothly again.