Project Overview: This guide provides a step-by-step process for connecting a dishwasher drain, suitable for intermediate skill levels. The working and total time required is 1 hour and 30 minutes, with an estimated cost of $15 to $25.
Understanding Drain Options: When installing a dishwasher, it’s crucial to know the different options for connecting the drain hose to either a garbage disposal or directly to a drain.
If replacing an old dishwasher, copying the drain hookups from the previous model is often the easiest approach. However, for first-time installations, a Y-branch tailpiece may be required to facilitate the flow of dirty water into the drain system.
Drain Variations: You may encounter several drain configurations:
1. A drain line connected through an air gap to the garbage disposal.
2. A drain line connected directly to the drain via an air gap.
3. A high-loop configuration to the garbage disposal.
4. A high-loop configuration directly to the drain.
An air gap fitting is a safety device that prevents back-siphoning of dirty water into the dishwasher. Not all dishwashers use this; some opt for a high-loop installation to prevent backflow.
Tools and Materials: The tools and materials needed will vary based on the configuration and whether an air gap is present. Always turn off the water and unplug the garbage disposal before starting.
What You’ll Need:
– Screwdrivers
– Utility knife
– 7/8-inch (inside diameter) drain hose
– Hose clamps
– Y-branch drain tailpiece (if needed)
– Garbage disposal drain adapter (if needed)
– Pipe clamp or pipe strapping (if needed)
Instructions:
Drain Connection With Air Gap and Garbage Disposal:
– Cut the dishwasher drain hose to reach the smaller tailpiece on the air gap fitting.
– Connect the hose to the air gap using a hose clamp.
– Connect the large end of the air gap to the garbage disposal with a 7/8-inch rubber hose.
For more assistance, consider consulting a local plumber.
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When connecting the dishwasher drain, it’s crucial to use hose clamps at both ends: one on the air gap and one on the garbage disposal inlet nipple. Be warned, the 7/8-inch hose must be free of kinks to prevent restricted water flow and potential blockages. If the hose is too long, trim it to size to avoid kinking.
Drain Connection With Air Gap (But No Garbage Disposal): To connect a dishwasher drain with an air gap but no garbage disposal, the drain hose is indirectly tied to the sink drain through the air gap. First, connect the dishwasher drain hose to the small side of the air gap, which is mounted on the countertop or sink deck. You may need to apply some force to slide the hose onto the air gap fitting. Next, use a 7/8-inch rubber hose to connect the larger side of the air gap to the Y-branch tailpiece on the sink drain. If your drain lacks this tailpiece, installation is necessary. Y-branch tailpieces come in two sizes, so select the one that fits the 7/8-inch hose running from the air gap. Secure both ends of the hose to their tailpieces with hose clamps. Ensure there are no kinks in the tubing before clamping the hose in place. Drain Connection Using High Loop to Garbage Disposal: Before installing this dishwasher drain connection, ensure local building codes permit the high loop method instead of an air gap, as the high-loop method may not be allowed in some areas. Prepare the Drain Hose: Pull as much of the drain hose as possible from behind the dishwasher to create the high loop before connecting the dishwasher hose to the garbage disposal. Loop the Drain Hose: Pull the dishwasher drain hose up and strap it as high as possible under the sink. This high loop prevents wastewater from siphoning back into the dishwasher from the garbage disposal. Use a large pipe clamp or flexible pipe strapping to secure the hose to the underside or wall near the countertop. Connect the Hose: Connect the dishwasher drain tube directly to the garbage disposal with hose clamps. You may need a dishwasher connector fitting, with one end attaching to the smaller drain hose and the other end having a larger 7/8-inch fitting that attaches to the garbage disposal. Tip: If the dishwasher isn’t draining correctly after connecting the hose, check for kinks in the hose and clogs in the drain basket or hoses. Also, inspect the air gap cylinder, which connects the drain hose next to the drain pump. If it’s dirty or clogged, it can cause draining issues. Drain Connection Using High Loop Directly to Drain: Again, verify local building codes to ensure the legality of the high loop method in your area.Loop the Drain Hose. Pull as much drain line as possible from behind the dishwasher. Loop it as high as possible under the sink and strap it in place. This will prevent wastewater from the sink drain from siphoning back into the dishwasher.
Attach Hose to Sink Drain. Attach the end of the dishwasher drain line to the Y-branch tailpiece on your drain, securing it with a hose clamp. Y-branch tailpieces that match the size of your dishwasher drain hose can be purchased.