You flip the switch. The disposal hums. But nothing grinds. That humming sound means power is getting to the motor, but the grinding plate isn’t turning. Most of the time, this is a simple jam, not a dead motor. Before you call anyone, there are a few things you can check yourself in about ten minutes. Here’s what to do, what it means, and when to stop.
What You’re Hearing and Why
That hum is the motor trying to start. It’s getting electricity, but something is keeping the flywheel—the spinning plate inside—from turning. Usually, it’s a stuck impeller or a foreign object wedged under the plate. Sometimes it’s a seized motor bearing, but that’s less common. Let’s rule out the easy stuff first.
The 5-Minute Reset: What to Check
1. Turn off the power at the breaker. This is not optional. Stick your hand in there with the power on and you’ll lose fingers. Go to your electrical panel and flip the breaker for the disposal or the kitchen circuit. Confirm it’s off by trying the switch—nothing should happen. Now you’re safe.
2. Look inside with a flashlight. Shine a light down into the disposal. You’re looking for anything obvious: a bottle cap, a piece of glass, a metal utensil, a bone fragment. If you see something, use pliers or tongs to pull it out. Do not stick your hand in there even with the power off—there could be sharp edges. If you see nothing, move on.
3. Manually turn the flywheel from below. Most disposals have a hex-shaped socket on the bottom center. That’s the flywheel shaft. You need a 1/4-inch Allen wrench (sometimes a hex key). Stick it into the socket and turn it back and forth. You should feel resistance, then it should free up and spin freely. If it won’t budge, something is wedged tight. If it spins easily, the jam is cleared.
Labeled diagram: The hex socket (for Allen wrench) and reset button are typically on the bottom center of the unit. On models like InSinkErator or Waste King, these are standard.
4. Check the reset button on the bottom of the unit. Look at the underside of the disposal. You’ll see a small red or black button. If it’s popped out, the disposal tripped its internal thermal overload. Push it in firmly until it clicks. This resets the motor’s safety cut-off. If it won’t stay pushed in, the motor has a more serious problem.
5. Restore power and test. Flip the breaker back on. Run cold water—always run cold water when using a disposal, never hot. Flip the switch. If it runs normally, you’re done. If it hums again, stop immediately. Running it while humming for more than a few seconds can burn out the motor windings.
What Each Check Tells You
If the flywheel turned freely with the Allen wrench but the disposal still hums, the motor is likely seized internally. That means the bearings or the motor windings are shot. This is not a homeowner fix. The cost of trying to force it yourself is a ruined motor, which means replacing the whole unit.
If the reset button popped out but the disposal works after you push it, that’s normal. It just overheated from the jam. But if it pops out again after a short run, you have a slow drain, a stuck impeller, or a failing motor. That’s worth having a tech look at.
If you found a foreign object and removed it, the disposal should work fine. If it doesn’t, something else is wrong.
Cost Comparison: DIY vs. Service Call vs. Replacement
Here’s a quick look at what you’re looking at cost-wise:
| Option | Typical Cost | |——–|————–| | DIY fix (Allen wrench, flashlight) | $5 (if you don’t already have tools) | | Service call (tech clears jam or resets) | $100–$150 | | Replacement (new unit + labor) | $200–$500 |
That $5 Allen wrench is worth a shot before you spend a hundred or more. Most jams clear in under a minute.
Video: How to Turn the Hex Key
Here’s a quick 60-second video showing exactly how to use the Allen wrench on the bottom of your disposal. Watch the turn—it’s that simple.
[Embed video: 60-second demonstration of hex key turn on disposal bottom]
Frequently Asked Questions
Q: Can I use a broom handle to unjam it? A: No. Don’t do it. Sticking a broom handle or screwdriver down into the disposal can crack the housing or break the impellers. That turns a simple jam into a full replacement job. Use the Allen wrench from below—that’s what it’s there for.
Q: What if the reset button won’t stay pushed in? A: That means the motor’s thermal overload is tripped and won’t reset, or the motor is internally damaged. You can try letting it cool for 30 minutes, then push the button again. If it still won’t stay, the motor is likely shot and the unit needs replacement.
Q: Will running cold water help if it’s humming? A: Cold water helps during normal operation, but if the disposal is humming and not spinning, running water won’t fix the jam. It might even hide the sound. Always turn off the power and clear the jam manually first. Then run cold water when you test it.
When to Stop and Call a Pro
If you’ve done the steps above and the disposal still hums, stop. Do not keep flipping the switch. Do not stick a broom handle or a screwdriver down there to force it—you’ll break the impellers or crack the housing. A cracked housing means replacing the entire disposal, which runs $200 to $500 for the unit alone, plus labor.
Also, if you smell burning plastic or see smoke, turn everything off and call a tech. That’s the motor insulation melting.
If you’re in Denton, Little Elm, Frisco, or Lewisville, S&W Service & Repair LLC handles garbage disposal repairs for all major brands—InSinkErator, Waste King, and others. We see this humming issue all the time. Sometimes it’s a quick fix like a stuck impeller or a tripped reset. Sometimes it’s a bad motor that needs replacement. Either way, we can tell you in a few minutes without charging you for a new disposal you don’t need.
For more on when it’s time to replace your disposal, check out our guide on disposal replacement signs. And for keeping your whole kitchen running smoothly, see our general kitchen appliance maintenance guide.
A Note on Warranty Work
If you have an Old Republic Home Protection (ORHP) warranty, we handle those work orders. Just give us a call with your policy number. We’ll come out, diagnose it, and if it’s covered, you’re set.
The Bottom Line
A humming disposal is almost never a mystery. It’s either a jam you can clear yourself or a motor that’s done. The 5-minute reset costs you nothing but a few minutes. If it doesn’t work, don’t make it worse. Call a tech.
Call S&W Service & Repair LLC at 940-286-4094 or book online to schedule a same-day appointment. We cover the entire North Texas area, including Denton, Little Elm, Frisco, and Lewisville. No fluff, no upselling—just honest work.