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How to Install Garbage Disposers

General Installation Instructions for Garbage Disposers
confused Here is a list of some tools and materials you may need to help you install a Garbage Disposer:
      • Flatblade and Phillips head screwdriver
      • Pipe Wrench
      • Hammer
      • Wood Dowel or steel punch
      • Hacksaw
      • Bucket
      • Towels
      • Electrical power cord
      • Electrical cable/cord clamp
Always turn off electrical power at the circuit breaker or fuse box to the circuit that serves the receptacle for the garbage disposer before beginning any work.

Replacing A Disposal
If you are not familiar with electrical power and procedures, we recommend you contact a qualified electrician. Always turn off electrical power at the circuit breaker or fuse box to the circuit that serves the wall receptacle for the garbage disposer before beginning any work. Unplug the disposals electrical plug from the wall receptacle. Disconnect and remove the existing disposer sink flange and waste assembly to the trap. Have a bucket and some towels handy to catch any water or debris.

Use a pipe wrench to disconnect the drain line where it attaches to the disposer discharge elbow tube. Remove the disposer from the sink flange by turning the mount ring to the left (clockwise). Be sure to support the disposer while performing this step or it may fall when the mounting ring is disconnected from the disposals mounting assembly.

If you are unable to turn the mount ring, lightly tap on one of the extensions or ears of the mount ring with a hammer. Some mounting systems have tubular extensions. Inserting a screwdriver into one tube will provide additional leverage for turning the mount ring. Some disposers may require the removal or loosening of nuts from the mount screws. Some disposers may require the removal of a clamp. If your disposal is hardwired, then once the disposer is removed, turn it upside down and remove the electrical cover plate. Use a screwdriver to remove the green ground wire.

Remove the wire nuts from the black and white power wires and separate the disposer wires from the electrical power cable. Loosen the screws on the cable clamp and separate the disposal from the electrical power cable. Remove the remaining flange and mounting system from the sink.

If you have "3-Bolt" mounting system then loosen the three mounting screws. As you push the mounting ring up, use a screwdriver to pry and pop off the snap ring. Once the snap ring is removed, the mount ring and the protector ring will be free to slide off the flange. The gasket may be squished against the bottom of the sink and may need to be pried off with a flatblade screw driver. Pull the disposer sink flange up through the sink and clean off all of the old putty from the sink.

If you have an "EZ Mount" mounting system then simply lift the mounting ring up and remove the rubber cushion mount. Just grab the rubber cushion mount with your fingers and pull it away and down from the bottom of the sink flange. The mounting ring will drop right off. Now unscrew (counter clockwise) the support ring from the sink flange. Remove the rubber gasket and the fiber (paper) gasket. The rubber or fiber gasket may be squished against the bottom of the sink and may need to be pried off with a flatblade screw driver. Pull the disposer sink flange up through the sink and clean off all of the old putty from the sink.

Installing the New Disposal - EZ Mount System
To install the disposer flange on stainless steel sinks, the rubber gasket is used instead of plumbers putty. Place and slide the rubber gasket around the underside lip of the disposal flange and insert the flange into the sink opening. Do not rotate the sink flange once it is seated.

For other types of sinks use a good grade "plumbers putty." Regular plumbers putty is not good for every type of sink. For stone, granite, marble, and other porous surfaces we recommend you use the "Amazing Sta Put Ultra" Plumbers Putty.

Make a worm by rolling the plumbers putty back and forth on a clean surface. Make the worm about the diameter of a pencil and long enough to surround the circular underside lip of the flange. Place the flange upside down and apply the plumbers putty around the underside lip of the flange. Now place the flange through the drain hole of the sink. Attach the fiber gasket (paper friction ring) underneath the sink by sliding the fiber gasket onto the exposed sink flange. Now with the arrows on the support ring pointing up, screw the support ring onto the sink flange. As you tighten the support ring, any excess plumbers putty will be squeezed out around the lip of the flange. This excess plumbers putty can be removed with your hands and put back into the container as it can be reused for any future use. Tighten the support ring hand tight until the flange does not move.

At this point you may want to insert the stopper into the sink flange and fill the sink with water to check the sink flange seal and insure there are no leaks. Place the mount ring over the sink flange and hold the mount ring in place while installing the cushion mount (large side down) so the groove on the inside of cushion mount fits over the lip at the bottom of the sink flange, similar to putting the lid on a plastic container.

When the cushion mount is installed correctly, the lip of the sink flange fits into the groove on the inside of the cushion mount and the mount ring can be pulled downward over the cushion mount and will be free to rotate. The bottom bead of the cushion mount acts as a gasket between the bottom of the sink flange and the top of the disposer.

Connect the waste elbow to the disposal by sliding the elbow gasket against the lip of the elbow. Some gaskets have a groove on the inside and are designed to fit and snap over the lip of the elbow.

Slide the elbow flange up against the gasket and insert the gasket end into the discharge hole of the garbage disposer. Use the two screws provided with the flange and tighten the flange to the side of the disposer. Some flanges snap into place on one side and use only one screw on the other side.

Connect the Garbage Disposer to 110-120 Volt, 60 Hz AC current only.


If a plug-in electrical cord is used, use a three prong plug. Remove the cover plate. The "Ground" wire should be attached to the ground screw in the bottom of the end bell. When viewing the face of the electrical plug with the grounding pin at top, the larger left blade is to be connected to the "white" wire on the garbage disposer. From the larger left blade, trace back to the end of the electrical cord to the bare wire lead. Attach that lead to the "white" wire from the garbage disposer.

Attach the smaller blade lead wire on the electrical cord to the black wire on the disposer. Use a cable clamp (strain relief) connector and install it into the hole of the disposer where the electrical power cord enters the disposer. Garbage Disposers must be grounded. In the event of a malfunction or breakdown, grounding provides a path of least resistance for electric current to reduce the risk of electric shock. The electrical plug must be plugged into an appropriate receptacle outlet that is properly installed and grounded in accordance with all local codes and ordinances.

If you will be wiring the Garbage Disposer directly to the house current (Hard Wired) (see the instructions below at the bottom of these instructions**)

Line up the garbage disposer underneath the mounting assembly. Guide the hopper projections, at the top of the disposer, into the slots on the mount ring. Turn the mount ring about 1/4" to the right so that the disposer is temporarily supported. Turn the mount ring and disposer until the disposer elbow lines up with the "p-trap" if attaching to a single bowl sink. If attaching to a double bowl sink then line up the disposer elbow to the continuous waste outlet.

Turn the mount ring to the right (counter-clockwise) until it locks tight to the disposer. If needed, gently tap the mount ring ears with a hammer until the lock position is achieved. If the mount ring is hard to turn, you may add a small of amount of liquid soap to the hopper projections. The "hopper projections" must be to the extreme left of the mounting slots.

If a dishwasher will be connected to the Garbage Disposer, then an Air Gap must be used. The Air Gap must be installed on top of the sink or countertop. Make sure the disposer "knock out" plug is removed before attaching the hose to the disposal dishwasher discharge inlet. Use a blunt instrument (steel punch or wood dowel). Do not use a screwdriver or sharp instrument.

Connect the smaller 5/8" hose attached to the dishwasher to the smaller 5/8" diameter inlet of the Air Gap. Using a #12 stainless steel hose clamp, attach the 7/8" diameter hose from the outlet of the Air Gap to the dishwasher discharge inlet on the disposal. Make sure the 7/8" diameter hose is not too long or it may droop. Also make sure the 7/8" diameter hose is not too short causing it to be kinked. If the hose is drooped or kinked the dishwasher will not drain out of the air gap properly and the water will be forced to exit out the top of the air gap, spewing water into the sink.

Turn on your water and check for leaks. Enjoy your new garbage Disposer!

Some Tips for Successful Operation
Make sure the garbage disposer is empty before using your dishwasher so your dishwasher will drain properly. You may want to leave the stopper in the disposer flange when the garbage disposer is not in use to prevent utensils and/or other foreign objects from falling into the disposer. Garbage Disposers will NOT grind or dispose of such items as plastic, tin cans, bottle caps, glass, china, leather, cloth, rubber, string, clam and oyster shells, aluminum foil, feathers, uncooked rice, to name a few.

**Wiring the Garbage Disposer directly to house current (Hard Wired).
Garbage Disposers must be connected to a grounded, metal permanent wiring system or an equipment grounding conductor must be run with the circuit conductors and connected to the equipment-grounding terminator or lead on the appliance.
A. If you use BX cable:
  • Install the cable clamp connector in the hole in the disposer.
  • Connect white wire to white lead of disposer.
  • Connect black.
  • Connect bare ground.
If BX cable is not used, provide a separate ground wire to the nearest cold water metal pipe or other suitable ground, using the screw in the bottom of the end bell for the ground wire.

B. If your power supply does not include a ground wire, you must provide one unless a metal cable is used. Attach a copper wire securely to the disposer ground screw and attach the other end of the wire to a metal cold water pipe. Use only UL approved ground clamp. If plastic pipe is used in your home, a qualified electrician should be called to install a proper ground.