Bosch Dishwasher Won't Drain, Fix the Clogged Drain Hose
How to fix a dishwasher that won't drain
Dishwasher Not Draining
After our Bosch dishwasher completed a washing cycle, the bottom of the dishwasher is still full of dirty water. There is a pump in the dishwasher that pumps the water out of the dishwasher through the drain hose. The drain hose typically runs from the dishwasher to the sink or the air gap. Our dishwasher has the air gap that fits into the top of the sink. From there, another hose connects to the split in the air gap and connects to the garbage disposal.
To troubleshoot the problem, I first checked the filter in the dishwasher looking for something that could be blocking the flow of water. There is a screen in the dishwasher that is supposed to block large pieces from going into the drain hose, but sometimes, small pieces of food can get through and clog the hose. The next thing I did was get a bucket, a pair of pliers and a screwdriver to remove the drain hose from the air gap. I emptied the water in the hose into the bucket and looked to see if it was blocked. As far as I could see, the hose was unclogged, so I was on to the next piece, the air gap. I unscrewed the air gap from the sink and then there is a clip that goes in the top that I was able to remove. Once I popped the top of the air gap off, I could see the clog. I took the screw driver and pushed out the bits of carrots that were clogging the line. Once I did that, I put the air gap back together, screwed it back into the sink, re-attached the drain hose and the hose to the garbage disposal and then ran the dishwasher on a rinse cycle to make sure the dishwasher completely drained and that the hoses I had fiddled with weren't leaking water under the sink.
All was good and I didn't have to call a plumber, although I did spill a bit of water on the floor. This was the first time I've taken the drain hose and air gap apart to fix a clogged line. The entire project took me under two hours to complete. The next time I do it, it should take less than 1/2 the time, but I wasn't familiar with troubleshooting this type of problem and needed to learn how to do it. The best part was I didn't need to get any replacement parts to fix the draining issue.
Buy a replacement dishwasher drain hose
 | Amazon Price: $1.72 |
 | Amazon Price: $17.51 List Price: $19.99 |
 | Amazon Price: $15.68 |
Buy an Air Gap for a dishwasher
 | Amazon Price: $16.45 List Price: $28.55 |
Comments
Thank you for letting us know the problems with draining in a dishwasher.
To avoid all this rinse you dishes before you put them into the dishwasher. Thank you for pointing our the trouble and how to deal with it.
Great information. It helps to have the information from someone who has experienced it first hand. Even the responses & comments are helpful advice and appreciated. Thanks for sharing.
Well done you. These jobs often turn into huge expensive ones
Prevention is better than cure: scrape the plates before putting them in. However, it can be beyond difficult to train all members of the family to do so.
Congrats on fixing this yourself.
that was a good hub regarding dishwasher problems and their maintanence.
this reminds me of Billy Connolly, the Scottish comedian, where he talks about vomit and asks how come it always contains carrots... even if you have not eaten any...
OMG, they are like Triffids, they are attacking dishwashers... ;-)
Good hub, I had a dishwasher with the same problem. We kept having to call the repairman, because neither of us knew how to fix it. Finally, we just resumed doing dishes by hand.
These are some great tips.
Very Good info! I've never had this problem, but it's likely to happen sooner or later. :)
I once peeled carrots in the sink and then removed all but the tinyist little bits. Those got washed down the drain. And clogged it. Love carrots, but handle with care! And I'm impressed with your skill. First, you have to know what you're looking at, and what it does. Way beyond me!
Good Job, Paul! It is best to try to troubleshoot the problem first before calling a repairman.
Above all method of unclogging the drainage, removing the blockage physically is the most effective one. It is a long term solution for clogged drainage that homeowners should try at home to avoid spending bucks of money.
Just cleaned ours out and found some pumpkin seeds! Thanks for the helpful post!
Great post. It saved me a call to a repair man.
Great post. I used my steam vacuum cleaner to suck the water out of the dishwasher and then to suck water out of the drain hose. A bunch of pumpkin seeds came out. I did not put any pumpkin seeds into my dishwasher. They must have come from my garbage disposal. It's always a good idea to run the disposal before running the dishwasher. I do not have an air gap, most likely because my dishwasher was installed by some folks who are less than professional -- my dad gave me the dishwasher as a gift and used his people to install it, not professionals, such as you would get if you bought directly from Lowe's or Sears. Anyhow, these folks have done other jobs at my house, and their lack of knowledge regarding codes is astounding. They "repaired" a backflow preventer on my sprinkler system by installing a cheapo non-backflow preventer connector. Guess what? I soon had "air hammer," loud knocking in my walls. When I insisted that they do the job over with an backflow preventer that I purchased, the knocking went away. They also installed a microwave too close to the stovetop, so they had to redo it, and now I have two huge holes in the tile underneath my microwave. Beggars can't be choosers, and all of this was my dad's gifts to me, but I'd rather not have my house burn down due to code violations on a microwave or poison my family with backflow from my yard entering my drinking water supply. And now this! Yikes. I guess I need to install an air gap myself, or always remember to run the garbage disposal before running the dishwasher. Thanks for walking me through this!
Great comments and helpful I am off to pursue fixing mine. I have water at the base of it and od not want expensive repair costs.
gredmondson 21 months ago
Some plumbing codes insist on air gaps, the purpose of which is to prevent water from the drain, or garbage disposal in Paul' case, from back flowing into the dishwasher. There are other devices besides air gaps that perform the same function. One of the reasons air gaps get clogged is that the filter screen will not be secured properly in the bottom of the dishwasher.