Germy Water in Dishwasher

I used Liquid-Plumr foam quite successfully. It is intended for partially blocked pipe. You can make your own version of the regular stuff, google the ingredients, but the foam works well on partial clogs.

I recently installed a dishwasher, and the directions were very specific about looping the drain hose, (from dishwasher to sink drain), above both the sink and the dishwasher. It prevents the type of backflow you are describing.

Like this:

My Dish washer has that loop, the cupboards even do not allow me to install it any other way. Then I had a smell problem and water left in the dishwasher. apparently a blockage. I got rid of it by applying pressure to the outlet hose and I scooped up all the dirt inside the dishwasher. A back up valve would have prevented me from doing so.

The other thing was that the drain from the sink was partially blocked. After a good chemical clean everything works and there is no smell anymore nor water left in the dish washer.

Its lots of fun to get it back to work and lots of brownie points can be earned.

Bownie points are good; especially when they're easy.

Back to the OP: The blockage is likely in the P trap. Maybe just take it apart and clean it out or replace it. Heavier particles settle in the bottom of the U.

No, I said I used a snake, and to use it I had to remove the trap. It was completely clean. The snake didn't come back with anything either, so the restriction must be more than 50 feet away. I plungered a lot to no avail, but that may be why the trap was clean. I have never found Liquid Plumber to work, but sometimes Draino does. I hesitate to use it because it will most likely kill the bacteria that I want to propagate. If it does not work then the sediment adds to the restriction.

I think you can purchase the bacteria and added back. I believe it is available for septic systems.

Thanks, I will try that right now.

It worked! I gave you a GA. Problem is solved.

Hehe who would have thought! I jump in and completed that GA for Kevin (not that he has not enough) gotta go

Mine has an anti-syphon valve in the top of the loop, mounted above the sink, I guess its simply a check valve. When I had the problem, I checked everything checkable, I have a disposal, but the blockage was in the pipe to the stack, well beyond the trap. I made a hole in the clog but couldn't completely remove it so I tried the LiquidPlumr, and that finished the job.

BTW, a good way to clean the dishwasher is to run it, empty, with Tang instead of soap. I guess the acidity moves soapy deposits. It does work.

The biggest problem for me is cleaning the drain inside the dishwasher, I though that the pump, would leave it dry so I tried the wand on the vaccum and got a soaking bag of dust to remove. Lucky me, the wet didn't reach the motor.

Supposedly, our dishwasher has some type of grinder thingy in it that grinds up food debris. I told my wife to not even think about putting anything in there with any food clinging to it. Those gimmicky features are the first to break.

You are the only one to respond so far an the anti-siphon valve. Specifically I wanted to know whether water comes out of the air gap and wets the top of the cabinets when the pipe is clogged. I would think so. Although this is better than running under the sink unnoticed, I still would not like it. My problem is solved now, but I am curious if the Liquid Plumber you used was a special type.

I'm not voting on this post because, while a good idea, it may not work in theory. When the pipe is clogged, the water will back up in the sink & there will be no way to get air in the drain hose. The water can be siphoned back even with the loop higher than the disposal. I will do mine that way tomorrow and report back. I was asking about experience with the air gap anti siphon valve as described in my link and shown here.

A loop will not stop a back flow. After the dishwasher pumps out, their will be a siphon that will pull water back from the sink to the dishwasher. The loop is to reduce the chance of sink water backing into the dishwasher when the sink is drained. A sink full of dirty water because of a clog below the point where the dishwasher drain comes in is a flood waiting to happen. If the dishwasher is run, the sink full of dirty water will be pulled back into the dishwasher after the first pump out. The only way to stop the siphon is an anti-siphon, which has a vent in it to break the siphon so that only water that came from the dishwasher falls back into the dishwasher. This water is expelled after the pre-wash part of the next cycle. Dish washers usually do not use check valves because they clog and stick open because of small food particles.

As for the sizes of the piping, that is the source of a lot of service calls because of clogging where the pipe size reduces. -- JHF

You are right, and as I suspected. I now have the high loop in place, but it did nothing to stop the siphoning of the dirty water back into the dishwasher. It may have helped for the other things you mentioned.

Two things come to mind: First, the vent to the roof must be clear, second, where the pipe exits the house there should be two pipes connected for cleanouts, one going in each direction. You said the clog was 50 feet, if you run your drain snake down the cleanout you should be able to find the clog. Cleanouts are sometimes sticking up out of the ground and sometimes just under the surface. Hope that helps, good luck!

The vent to the roof must be on the other side of the clog. All other sinks & toilets are working fine. There is a cleanout on the wall near the floor of the basement (about 10 feet below the dishwasher trap). It's difficult to get to with my wife's boxes around there. The snake would have to make a 180 degree turn to go under the concrete to where the clog must be. I don't think that is possible. My snake is only 50 feet, and didn't do the job, but may not have got that far. It likes to twist up. I'm going to look for a longer snake with a larger diameter.