Dishwasher hook up

[melissaA]

I just moved into a new home and got a used dishwasher, and have no clue how to hook it up. Ive looked up online trying to find websites that show how to hook up dishwashers but can not find any.. If anyone knows of any sites i would appreciate it. One with pictures would help alot.

[LazyPup]

MellissaA

The plumbing code requires a dishwasher drain line to be connected to the house drain by means of an indirect waste connection. If you have a garbage disposal the dishwasher drain line MUST BE connected to the dishwasher drain input port on the upper part of the disposal. (the code prohibits connecting a dishwasher to the drain lines downstream of a disposal.)

When connecting the drain line to a disposal inlet port be sure to knock out the "knockout plug" in the dishwasher inlet port before attaching the drain line.

If you do not have a disposal the code requires the dishwasher drain line to be first connected to a "Dishwasher Air Inlet valve" which must be attached to the sink or countertop so that the air inlets are above the top rim of the sink.

A second piece of drain line is then attached to the discharge port of the Air inlet valve and connected to a "dishwasher inlet tube tailpiece".

For the water supply saddle tap valves are prohibited.

The easiest way to connect the water line is to replace the existing sink "hot water angle stop valve" with a side outlet angle stop valve. (the valve side outlet angle stop valve has two 3/8" compression outlets, one on top which is connected to the sink, and a second one on the side that will permit a 3/8 inch copper line to the dishwasher.

If you have 1/2" copper tubing to the sink you can turn the water off at a zone valve or at the main, then remove the existing angle stop and replace it with the side outlet angle stop.

NOTE: if your existing angle stop is soldered on you can cut it off, then use a 5/8 compression x 3/8compression valve. The 5/8 compression inlet will fit directly over the copper pipe and can be tighted with an adjustable wrench so you will not have to solder anything.

If your existing angle stop is a 5/8 compression type, you can unscrew the nut on the pipe to release the existing valve. (The nut is held on the pipe by an intermal compression sleeve and will not come off the pipe. Leave that nut and compression sleeve in place, remove the nut and compression sleeve from the new valve, slide the valve on the pipe and tighten it in place with the existing nut.

I am attaching illustrations for both the water supply and the drain connections.

You should have an electrical outlet installed under the sink and the electrical service is then connected by a plug.

[kactuskid]

Just to add to Lazypups excellent advice, you will also require an electrical receptacle to supply power to this dishwasher. It should be on it's own 20 amp dedicated circuit, though it can share the circuit that the garbage disposal is on if it is a 20 amp circuit.

I would also suggest you purchase a dishwasher installation kit, this includes not only the double port valve but also a stainless steel braided hose for your water supply line. Here's an example:

http://catalog.plumbshop.com/Default.aspx?CatID=K175

Here's a couple of installation links that may prove helpful in the illustrations.

http://www.homestore.com/HomeGarden/HomeImprovement/HowTos/HowTos/CRHO_InstallingDishwasher.asp?poe=homestore

http://www.hometips.com/articles/dishwasher.html

[thinkerbee]

Thanks for all the info Lazypup. One question - Do I need to have air inlet valve (is this the same as an air gap?) at all if I have a disposal? Can't I just attach the drain connection directly from the dishwasher to the disposal?

[LazyPup]

Thinkerbee,,
It would depend upon your local code. If you will look at my illustration for the drain hookup the bottom picture is the drain configuration for a disposal, just run the line up for the high loop then back down to the disposal inlet,,,but..some local codes require the air gap for all installations.