I do not have an air gap. My hose has an upper loop and runs into the drain after the trap. The sink drains fine but when I run the dishwasher, water backs up into the sink. I tried drain cleaner and run an auger into the lines and I don't see signs of a clog. I ran the auger 25' into the line which is almost to the septic tank. What should I do next. Thanks!

speedball1

You do not need a air gap if you have a drip loop installed in the drain hose.
You say, "My hose has an upper loop and runs into the drain after the trap."
AFTER the trap? Are you sure it doesn't drain into a branch tailpiece,(see image) BEFORE the trap? After the trap being downstream from it and allowing sewer gas to enter your dishwasher.
Has this been a ongoing condition or did it just start? Let me know, Tom

ricky lee

Thanks for the quick reply! The hose runs into what looks like a reducer coupling after the trap. It goes into the pipe right before the pipe goes into the wall. This just started happening within the last month or so. We've lived here 10 years.

speedball1

If your washer's connected after the trap then you have a direct connection between the washer and the sewer allowing sewer gas to enter the dishwasher and contaminate your dishes. And you say this has been going on for 10 years? Your diswhwasher drain is entrapped and presents a health hazard to your family. Have it looked at and repaired.
While you may have snaked the drain located in the wall you didn't get all the blockage out. Go back and snake it again and put out at least 6 foot of cable. Good luck, Tom

ricky lee

Tell me if picture attachment is good or not.....

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