The first step is to run the water line. Drill a hole behind the refrigerator, and then one underneath the sink. Go down into the crawl space. Feed the line down, and then up through the refrigerator hole.
Whenever drilling holes for water lines, always be sure to use a paddle bit that's one to two sizes larger than the water supply line to prevent the line from kinking.
Now that the water line has been run to the refrigerator, it's time to do what's called the "tap-in" to the cold water line underneath the sink. To tap into the line, shut off the water to the house at the main. Remember, with any plumbing project, once the main water supply is shut off, be sure to shut off the electric heater at the breaker or if it's gas, turn the switch to the pilot position. Finally, drain the lines by opening a faucet.
Now that the water's off, install the new valve for the icemaker water line. There are a few different types of valves that can be used. For a DIYer, if codes allow -- a needle valve is recommended. A needle valve is hollow, which will actually pierce the pipe and tap-in quickly. It's a very easy valve to use. To install a needle valve or saddle valve, place the two clamps around the copper pipe and use a screwdriver to tighten the screws on each side to hold the valve in place. Be sure to keep the spacing equal to prevent leaking. Next, tighten down the "T" handle until it's tight and pierces the copper line.
The first part of the icemaker kit is called the solenoid valve. Mount the solenoid valve to the dedicated holes found in the cabinet frame of the fridge using a drill and two 1/2" hex-head machine screws. Locate the 2-pin solenoid connector usually found tucked or taped under the refrigerator and insert the connector over the valve solenoid terminals as far as possible.
Attach the water supply line with the provided compression fitting to the top of the solenoid valve by screwing it into place then tightening it up with a crescent wrench. Using the plastic tubing provided with the kit, screw the plastic fitting to the water outlet on the bottom of the solenoid valve. To hold the water line in place, use the provided adhesive clips to run the water line to the back of the freezer. Once the water line is in place, use a screwdriver to puncture a hole in the paper cover on the back of the unit.
The next step is to install the factory fill tube. Use a flathead screwdriver to remove the plugs from the holes. It's a good idea to have a pair of needle nose pliers handy to grab the wiring harness behind the large hole in the back of the freezer. Pull it out a few inches (Image 1). Repeat this process with the water inlet plug and the mounting hole plugs located on the side of the freezer wall. Now move to the back and install the fill tube. Begin installing the fill tube by placing the provided metal insert into the end of the water supply line (Image 2). Slide the provided water valve clamp over the fill tube, insert the water supply line and use a drill with a hex head bit to tighten everything up. Attach the fill tube to the freezer by sliding the angled part of the tube into the inlet hole in the back of the freezer and screw it into place.
With all the work done on the back side of the freezer it's time to install the icemaker unit itself. To get power to the icemaker, plug in the wiring harness on the side of the ice maker unit into the wiring harness on the back of the freezer wall. Insert the extension tube into the smaller hole on the back of the freezer wall (Image 1). Screw the provided screws to the mounting holes on the side of the freezer wall (Image 2).
Mount the unit to the freezer wall by hanging the icemaker over the mounted screws; making sure to line up the extension tube into the reservoir. Tighten up the mounting screws to secure the unit to the freezer wall, and then add the ice bucket under the kit. Now that the ice maker is completely installed, plug in the refrigerator. Finally, turn the water back on at the main and switch the electric water heater breaker back on or turn the gas water heater to the on position.