The cost of purchasing a new dishwasher from a speciality retailer frequently includes the installation crew setting up the connections and sometimes even removal of the old dishwasher. However, installating the dishwasher is typically not included if you purchase it from a big-box home improvement store or an internet merchant; instead, you may have to pay a significant additional amount to have this done.
Thankfully, once the old dishwasher has been removed, attaching the dishwasher yourself is quite a simple task.
Prior to Starting
Three connections are needed to connect a new dishwasher: a drain line, a water supply connection, and a power cord connection. All of them are doable by DIYers if they know what is needed.
The easiest part might be making the power connection, particularly if you need to become more familiar with electrical wiring. Dishwashers can be “hardwired” by inserting an NM circuit cable straight into the dishwasher’s wire connection box; however, this is less frequent and just requires using an ordinary appliance cord that plugs into a wall outlet.
In any case, a dishwasher must be powered by a separate circuit per the electrical code; if yours needs to be wired this way, you might wish to have a new circuit installed when you replace the dishwasher. The NEC regulation will mandate GFCI protection for dishwashers starting in 2020. This is a superior approach even if it’s not necessary because it makes it simpler to disconnect the appliance in the event that servicing is later needed.
Process
You can wire the dishwasher yourself for any reason at all. The process for connecting an appliance cord or hardwired connection is the same; wires are connected within an access panel located at the appliance’s base.
It is simple to connect the water supply by attaching one end of a steel supply tube that has been braided to the dishwasher’s water input valve and the other end to a shut-off valve on a hot water supply pipe. You won’t have any trouble hooking up the dishwasher if you’ve worked on plumbing fixtures like sink faucets and toilets, as this supply tube is essentially just an extended version of the same type.
Dishwasher 90s, a unique brass fitting that forms a 90-degree elbow and makes it simple to connect the supply tube to the dishwasher, are typically attached before connecting the water supply tube to the dishwasher. Usually, the connection package that includes the braided steel supply tubing also comes with this fitting.
Bottom Line
A dishwasher’s drain hose connection is an equally straightforward plumbing task. The drain line attaches to an air-gap fitting or loops up to the bottom of the countertop beneath the sink en route to the drain trap beneath your sink. The right way to do this will depend on your local code requirements, but the goal of both approaches is to prevent soiled wastewater from recirculating into your dishwasher. The drain hose is connected to a nipple on the garbage disposal or straight to a nipple on the sink drain tailpiece as it loops back down.
