How to Install a Dishwasher to a Drain Pipe
- 1). Plan the route for connecting the dishwasher to the drain pipe. In most locations, this means routing the drain pipe for the dishwasher through cabinets. Measure the distance from the dishwasher discharge to the drain pipe and ensure that you have enough hose to connect the two. Purchase a drain hose extension, if needed.
- 2). Mark holes on the cabinets where you need to drill the holes for the drain pipe. Attach a spade bit of the proper size to a power drill. Drill out holes in the cabinet where needed.
- 3). File or sand down the edges of the holes. Smooth any rough edges that could damage the hose.
- 4). Run the drain hose through the cabinets to the drain pipe. It's OK if it is loose, as it will be fixed in place later.
- 5). Connect the dishwasher to the drain pipe. How this is done depends on the type of drain pipe connection. In some locations, the drain pipe will be a standalone type with an open top, similar to those used on washing machines. In this case, insert the gooseneck end of the drain hose into the pipe. Secure it with a plastic tie. In other installations, the end of the drain hose from the dishwasher will connect to the side of the drain pipe under the kitchen sink. To connect this type, slip the end of the hose over the pipe inlet nipple on the side of the pipe. You may need to trim the end of the hose to the proper nipple size. There should be markings on the side of the hose end. Slip the hose over the drain pipe inlet. Secure with a hose clamp.
- 6). Secure the drain hose to the side of the cabinet or wall with pipe clamps. The middle portion of the hose should be elevated so that it is higher than both the end on the dishwasher and the end on the drain pipe. This will prevent water from flowing back and possibly getting siphoned into the water supply.
- 7). Run a short load in the washer. Watch the drain hose and check for leaks. Tighten the hose clamps, if needed.
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