How To Fix Garbage Disposals

Here's how to diagnose and fix common garbage disposal problems. We'll determine whether the problem is the disposal, the circuit breaker, the pneumatic button, or the switch. Links to purchase parts for the repairs from Ferguson Plumbing in San Luis Obispo, CA are given at the end of the article.

When you push the disposal button on the sink, it pressurizes a rubber tube connected to the switch plugged in between the disposal and the AC outlet under the sink. The switch turns on, activating the disposal.

If your garbage disposal doesn't turn on when you push the button, it may be the disposal, the button, or the switch. It may even the circuit breaker in your main panel, although this is unlikely.

To fix it, try these steps, in order. Test the disposal after each step. Turn on the water before you test the disposal.

1,  Make sure the rubber tube is firmly connected to the button assembly under the sink top, and to the switch plugged into the AC outlet under the sink.  Make sure the switch is firmly plugged into the AC outlet, and the disposal is firmly plugged into the switch.

2.  Turn the breaker on the main circuit panel off, then back on to make sure it is reset and on.

3. Push the reset button on the bottom of the disposal, if there is one.

4. If the disposal hums, but doesn't turn, unjam it by turning it with the wrench in the socket at the bottom. (It's a large allen hex socket.)  If you garbage disposal doesn't have a allen socket, there's a tool that you insert through the top to turn the disposal.

5. Unplug the disposal from the switch, and plug it directly into the AC outlet. If it doesn't turn on, replace the disposal. If it does turn on, the disposer is ok, and the problem is either the button assembly or the switch.  I strongly urge you to replace BOTH the switch and the button assembly at the same time.  Failure of either may predict failure of the other.

The switch kit includes the button cap and finish ring around it, the plunger mechanism that mounts in the hole through the sink top, the hose, and the switch.  If the finish on your button is OK, you can replace the button and trim ring in the kit with your old set.  If the finish on your old button is NOT OK, and you can't buy a kit with the same finish, you'll have to buy a new button and ring separately. They are $21 at Ferguson plumbing.

Switch and button kits:

https://www.ferguson.com/category/appliances/appliance-parts/air-switches/_/N-zbq3f3

Tip:  It may be difficult to remove the button mounting nut under the sink top.  To replace a plastic button assembly, remove all metal or plastic rings surrounding the button on top of the sink & remove the button Then break up the remaining part CAREFULLY from the top with a hammer and wood chisel, so it falls through the hole.