Replacing dishwasher question about drain connections

[dylanmitchell]

Replacing a Badger 5 prior owners installed with an Evolution Compact. With only two people who don't cook a lot, it will see moderate use.

Looking for help understanding the drain connections. I see where the dishwasher and sink are connected to the air gap by the sink faucet. The extra line is running to a sink sprayer. I also see the disposer drain but don't see a drain hose from the dishwasher to disposal. The dishwasher will back up into the sink and I don't see a separate standpipe. Any idea where the dishwasher drain is going and how it's connected so it overflows into the sink? The powercord under the sink goes into the reeptacle that's connected to a wall outlet so no wiring challenges.

Also, beyond replacing the disposal are there any hoses or pipes I should replace while work is being done? Like to be proactive and replace things before they become a problem.

 

[Marky_Mark]

Your dishwasher is connected to the air gap.  Then the air gap is connected to the disposal.  There is no connection from the dishwasher direct to the disposal or any drain.

 

So the waste water from the dishwasher runs up to the air gap and then continues on down to the disposal, having passed through the air gap.

 

[combo52]

Air-Gap Backing Up

Did you knock the plug out of the DW port on the new disposer before you connected the air-gap drain hose to it ?

 

John L.

 

[Marky_Mark]

Ah ok.  I interpreted what you wrote in a different way to John!  When you said that "the dishwasher will back up into the sink" I thought you were just saying what you expect will happen with this arrangement.  But did you mean that you have tested it and found that the dishwasher is "backing up" into the sink by draining out of the air gap and pouring into the sink?  If so, then yes I would check that you remembered to knock out the little plastic plug on the new disposal's dishwasher inlet.

 

 

 

[dylanmitchell]

Diposer arrives this week, preparing for install

Thanks. Disposer is arriving this week and I wanted to make sure I understood the connections before installing. To clarify waster from the dishwasher only backs up into the sink occasionally and running the disposer clears the backup. I also have the air gap pointed toward the sink.

Makes sense that the dishwasher passes throught the air gap then into the disposer. I'll make sure to knock out the plastic plug. I've read that's a common source of issues.

 

[combo52]

Hi Matthew

 

If the sink drain is backing up when the DW drains you have a seriously restricted drain line that should be cleaned or replaced before you can use your disposer much if at all.

 

A kitchen sink drain should handle around 20 gallons of water a minute, a typical DW only drains at a rate of around 1 gallon a minute.

 

John L.

 

[dylanmitchell]

Scheduled plumber to check line and install

Have a plumber coming on Monday that can clean or replace the line and install the disposer. I appreciate the help and like understanding how things work even if we end up having a professional like a plumber do the work.