Johnson Tee and Dishwasher

Users who are viewing this thread

mcohen

New Member
Messages
4
Reaction score
1
Points
1
Location
WA
Hello,

When I moved into my current house several years ago, I noticed that the DW was having problems draining. Often the basin was wet and smelly. Occasionally, when we ran it, some water would leak onto the floor. I didn't pay too much attention to it b/c it was old and I knew we would replace it some day.

Recently, we did replace it with a GE Adora. I noticed that the basin does accumulate water in it. If I force the DW to drain itself, it is dry, the next morning there will be water in the basin.

It does NOT appear to be from the water supply, but from water backing up into it. When I pull out the filter basket in the basin, there are particulates on the "down stream" side of the filter, not the "up stream side." This points to waste water backing up (I think).

The manual and online blogs all point to the air gap. We do not have an air gap, but a Johnson Tee -- yes we live in Seattle. I checked the T. It does not appear to be blocked (at least at the top).

I am suspicious that the waste line is just clogged up from years of use. Seems like clog could be between the DW waste line and where it ties into the sink waste link (on either side of the Johnson Tee) or below the DW/sink waste line connection. I saw Terry's post on de-clogging the sink waste link, but I don't know how to clean-out the DW waste lines.

FYI, the waste line for the DW goes straight into the wall. So, the plumbing to the Johnson Tee and from the Johnson Tee to the waste line is all hidden behind drywall. I only have direct access to the DW waste line, the sink, and the vent on the Johnson Tee.

I would greatly appreciate your help.

-Mike
 

Reach4

Well-Known Member
Messages
38,798
Reaction score
4,412
Points
113
Location
IL
I did not follow much of what you described. However I would pull open the P trap to see what you can see. It's easy, and it may provide either a cure or at least some info. Don't forget the bucket.
 

Terry

The Plumbing Wizard
Staff member
Messages
29,942
Reaction score
3,458
Points
113
Location
Bothell, Washington
Website
terrylove.com
You can cut off the 3/4" cap on the outside wall and see if a small snake can clear it.
Below the Johnson see is a 1.5" standpipe and p-trap, which then goes into the 2" kitchen waste line.

johnson_tee_2.jpg


You can also bypass the Johnson Tee by installing an air gap on the sink and route the dishwasher drain to that, and continue to the disposal.

sink_dw.jpg


king-county-dw-1.jpg
 
Last edited:
Top
Hey, wait a minute.

This is awkward, but...

It looks like you're using an ad blocker. We get it, but (1) terrylove.com can't live without ads, and (2) ad blockers can cause issues with videos and comments. If you'd like to support the site, please allow ads.

If any particular ad is your REASON for blocking ads, please let us know. We might be able to do something about it. Thanks.
I've Disabled AdBlock    No Thanks