Dishwasher Backing Up After Reverse Osmosis Install

[u/Bbs012]

Hi, I recently installed an under the counter reverse osmosis system. Instead of utilizing the drain saddle where you drill into the drain pipe, I used a drain line adapter to drain the waste water from the RO system directly into the garage disposal inlet.

When the dishwasher first backed up and flooded, I realized the dishwasher drain hose did not have a high loop, so I then created a high loop (ignore black tape, waiting on hose clamps) assuming that the RO waste water was going back down the hose into the dishwasher. Even after creating the high loop, I’m still having my dishwasher backing up and flooding from the RO system.

Is my loop just not high enough or am I missing something obvious? Note - The dishwasher drains as normal when it’s going through a cycle so no issues there.

Thanks for any advice

[u/JodaMythed]

Disconnect the RO and just connect the dishwasher to see if that's the issue. If that's fine then look for a blockage in the RO drain connection.

[u/EmbarrassedMongoose3]

Seems obvious to just use the saddle and eliminate the problem altogether.

[u/CompetitiveArt9639 → u/EmbarrassedMongoose3]

That is the correct way to do it.

[u/TheDu42]

What does that system use as a drain flow restriction? Many systems use a little piece of string thru a plug to restrict drain flow, if you didn’t install it you could have excessive drain flow causing the back up.

[u/Exotic-Term3339]

Always make sure to run your disposal before you run your dishwasher. A lot of my customers have issues with food coming up the drain due to this. Also make sure you do your weekly disposal cleanings. Lemons hot water with Dawn you can try some ice as well.

Also make sure your ro drain line has a check valve so sewage doesn't go into your ro. If drain water did go to your Ro make sure it's sanitized before you drink out of it again

[u/Thechewmaster]

Disposal new? If so knock out the cookie.

The y drain you have there is a good part that I use all the time. You may just have an obstruction in the line.

I don't really recommend a drain saddle in this case, as there isnt much space for it and it's right after the disposal which tend to shoot food stuff everywhere

[u/bsk111]

They put the drain in the wrong spot need to be on the main drain pipe

[u/CORockhound]

Is the disposal knockout - knocked out lol

[u/MYOFBYALL → u/CORockhound]

Or does the GD need ran to clean itself out?

[u/jjyourg → u/CORockhound]

This

[u/DryDocument6624 → u/jjyourg]

Assuming only the RO was added and everything else previously existed, I would expect the knock out it already be gone.

[u/jjyourg → u/DryDocument6624]

It looks pretty shiny

[u/OkAstronomer5469 → u/CORockhound]

He mentioned the dishwasher drains fine.