How To: Garbage Disposals

These days it’s an uncommon household that doesn’t have a garbage disposal. They’ve come to be an expected kitchen plumbing appliance. At Advocate Master Plumbing we have performed garbage disposal repairs and installations of all kinds. And on this garbage disposal repair and installation page we will outline the way we do a few of the most common repairs with tips and videos.

If you’re in a hurry feel free to skip ahead by clicking one of the following links.

How to install a new garbage disposal

Installing a new garbage disposal is sometimes only recourse. There are relatively few garbage disposal repairs you can make. And if you’re sticking with the same brand of disposal your installation will be pretty simple. Below you’ll see a video and step by step instructions of how to install a new garbage disposal.

  1. Disconnect the power – Turn off the power to the disposal by pulling the fuse or switching off the circuit breaker that controls the unit. Most disposals have power cords that run from the underside of the disposal to a switch-controlled outlet under the sink. To be sure the power is off, we prefer to run the disposal while a helper at the main service panel locates the right fuse or circuit. When the circuit is shut off, the disposal will stop. If the outlet under the sink is corroded or otherwise in bad repair, we suggest hiring an electrician to replace it. You can’t be too careful when electrical connections are near water.
  2. Remove the disposal – Use a pipe wrench, a large adjustable wrench or a large pair of tongue-and-groove pliers to undo the slip fittings on the P-trap, and release the trap’s contents into a bucket. (You may also find a clean out plug on the underside of the pipe.) Once the P-trap is drained, remove hose clamps, discharge tubes and any other fittings that connect the old disposal to the drain pipe. Hold the disposal from underneath with one hand while you loosen the screws on the side of the mounting assembly. (The disposal probably came with a special tool for those screws, but chances are you won’t be able to find it. In that case, use a screwdriver.) Turn the assembly counterclockwise to release the disposal from its mounting.
  3. Disconnect the disposal’s electrical wiring – Once the disposal is disengaged, remove the screws securing its electrical cover plate, which is usually on the bottom of the unit. Then, to be doubly sure that the power is off, carefully remove the wire connectors that join the wires inside, and use a voltage tester to test individual wires. If there’s no current, pull the wires apart and loosen the clamp that holds the electrical cable. Pull the cable out of the unit.
  4. Remove the old mounting ring and sink flange – Use a screwdriver to pry off the snap ring on the old mounting assembly, and remove the screws that connect the mounting ring to the sink flange. Pull the mounting ring away from the sink flange and remove any backup rings, gaskets or other parts of the mounting assembly.From above, pry the sink flange out of the drain hole. Clear any remaining plumber’s putty, old sealing gaskets or other debris from the area before you install the new hardware.
  5. Disassemble the new disposal hardware – Most new disposals are shipped assembled, so you have to disengage the mounting assembly from the body of the disposal, then pry the snap ring off of the mounting ring with a screwdriver. This should unlock the separate pieces of the mounting assembly. If you have trouble with this step, consult the manufacturer’s directions.
  6. Install the mounting assembly – Apply a 3/8 inch bead of clear silicone around the rim of the sink flange where the rim meets the sink drain hole. From above the sink, press the flange into the drain hole.From underneath the sink, install the gasket, the backup ring if one comes with your model, the mounting ring and the snap ring over the neck of the sink flange. Tighten the screws on the mounting assembly, alternating screws as you tighten, until the ring is uniformly secure. Then, from above, remove any excess silicone from around the flange seal.
  7. Make the electrical connections Remove the electrical cover plate on the new disposal. Insert the power cable at least 6 inches into the disposal’s cord connection slot and tighten the clamp screws. Pull the cord’s wires and the unit’s wires together inside the disposal’s electrical box. As needed, strip and splice the white wires to white and black to black using wire connectors. Connect the green ground wire to the grounding screw on the disposal, then replace the cover plate.
  8. Connect the discharge tube to the disposal – Use the hardware provided to attach the discharge tube to the discharge outlet on the side of the disposal.
  9. Mount the disposal – Hold the disposal up against the mounting assembly, and turn the mounting ring clockwise until the disposal locks into place. Tighten the screws on the mounting assembly with a screwdriver or the tool that comes with the disposal. Rotate the disposal so that the discharge tube can be easily connected to the drainpipe.
  10. Install the plumbing – Connect the disposal to the P-trap and the trap to the drainpipe. (The layout of your drain assembly may vary, depending on space constraints and whether you have a one- or two-bowl sink.) Tighten the parts by hand, then finish the job with a pair of tongue-and-groove pliers.

How to repair a stuck garbage disposal

If your disposer is humming but not running when you flick the switch, there’s something caught in the grinder chamber. Follow these steps:

  1. Unplug your garbage
  2. Using the hex Allen wrench wiggle the motor back and forth. This should dislodge the offending material.
  3. With a flashlight inspect the inside of the garbage disposal.
  4. Use a pair of needle nose pliers to remove any offending material.
  5. Plug the garbage disposal back in and test with water. If it won’t come on you may need to push the overload reset button on the bottom of the disposer.

How to clean a garbage disposal

There are many theories about how to clean a garbage disposal. Many of them work. Many don’t. Watch the video below from Insinkerator garbage disposer company and we’ll get to some other methods, as well.

A persistent smelly garbage disposal is usually due to rotting food particles built up in the drain pipes and collar of the disposer. If you have a removable rubber baffle in the drain remove it and clean it. You can even put it in the dishwasher. Wipe down the drain collar inside and out. Remove the drain pipes connected to your garbage disposal and wash them. There can be grease and food build up inside the drains. Lastly, put about a half a cup of baking soda in the drain. Put the drain stopper cap on and let that set over night. In the morning remove the cap and put a cup of white vinegar in the disposer. Let that foam inside the garbage disposal. After another hour flush it out with warm water.

Why you should hire your plumber in Lee’s Summit

The luxury of a garbage disposal in your home can’t be denied. There are few homes today without one in their kitchen sink. But don’t be mislead. An improper garbage disposal repair or installation can be problematic. It can even be dangerous. Wiring a garbage disposal incorrectly can cause an electrical fire. If the drains aren’t correctly designed and installed you can cause clogs and water damage. If you’re not sure what you’re doing call us. We’ll respect your home and your budget.