If you plan to disconnect and remove your ice maker either for repairs or permanently to make more freezer room, capping the line that supplies water to the freezer helps prevent leaks. You can and should shut off the water to the refrigerator using the cut-off valve under your sink, but capping the line is still a good precaution. For instance, if you accidentally jostle the cut-off valve, which might occur if you remove cleaning products from beneath the sink and bump against the knob, water could begin leaking behind the refrigerator. Installing a cap takes only a minute.
Slide the appliance out from the wall to disconnect the power cord from the electrical outlet.
Turn the T-valve behind your refrigerator or under the sink clockwise to stop the flow of water through the line.
Use pliers to grab the metal nut on the end of the copper pipe where it connects to the back of your freezer. Twist the nut counterclockwise to loosen the connection, then pull the pipe out of the freezer.
Push the plastic water-line cap into the copper pipe and twist the cap like a screw to push it into the pipe as far as it will go. This watertight cap keeps your kitchen floor dry and prevents flooding if the cut-off valve is accidentally turned on, yet the cap can be removed quickly if you ever want to reconnect a refrigerator with an ice maker to the water supply.