In this video, This Old House plumbing and heating expert Richard Trethewey explains how to install a garbage disposal.
Steps:
1 Turn off the electrical power to the garbage disposal; use tester to ensure power is off.
2 Disconnect the electrical cable from the underside of the disposal.
3 Unbolt the drainpipe from the side of disposal.
4 Loosen locking ring and remove the old disposal.
5 Unscrew the mounting ring from underside of sink.
6 Remove the locking ring with a screwdriver.
7 Push out the sink flange from the drain hole in sink; clean away old putty.
8 Apply bead of plumber's putty around sink flange, then set it in drain hole.
9 Reattach mounting ring to underside of sink; tighten the screws.
10 Remove excess putty from around top of sink flange.
11 Reconnect the electrical cable to the disposal.
12 Attach the disposal to locking ring; tighten with screwdriver
13 Connect the tailpiece and rubber gasket for the drain line to the disposal.