How Should The Dishwasher Connect to Drain Pipe?
I really like this video for a lot of reasons. One the house is only a few years old so the video is great reminder that all homes need to be inspected regardless of age. It also thoroughly explains the purpose of p-traps under kitchen sinks, and how the dishwasher should be connected to the drain pipe under the sink. Maybe you don’t geek out about home inspection stuff as much as I do, but I hope you enjoy the video!
If you’re a curmudgeon and you don’t want to watch the video, I’ll keep it simple. P-traps prevent sewer gasses from entering your home. The water in the trap acts as a seal against the gasses. The dishwasher drain needs to connect before the trap. If it is connected after, then the sewer gasses will get into your dishwasher and then your home.