Dishwasher won't drain

It drained fine 2 days ago. Today? Niagara Falls out the front.

I checked the trap, and there was nothing unusual blocking the drain. I cleared it out, ran it again. When it switched to “drain” mode, nothing was pumped out. Nothing appears to be blocking the end on the garbage disposal, either.

There’s no airgap thingy on my sink or countertop.

How can I determine if it’s the pump or just a drain blockage?

Get yourself some drano and pour it into all your adjacent drains (but probably not in the dishwasher). Observe the action, and repeat if necessary. Try gently plunging the kitchen sink to suss out any blockages (you’ll feel it).

Shortly after I purchased my home I encountered a stopped-up kitchen sink and went at it with a plunger. I ended up removing the bathroom sink (1/2 bath adjacent to the kitchen) and hung a bucket on the elbow pipe to collect the fruits of my plunging. Disgusting. But those pipes have been clear ever since. I also had a graywater pipe clog, and had to apply draino upstairs to resolve that. That reminds me - I need to get some more draino for preventative maintenance…

Good luck

Do not put Drano on any drais connected to your dishwasher, and do not put Drano in your disposal, either.

If you start your dishwasher, most of them have a cycle that tries to pump out any leftover water. Do you hear the pump running when that happens? If so, you probably have a clogged drain hose. I suggest going to and looking up how to clear it. I am fairly certain they will not suggest drano.

The reason I say don’t put Drano in there is that it might not clear the clog (if it’s a peanut or cherry pit, for instance) and it may very well melt the plastic drain pipe from your dishwasher. And then, when the plumber comes, he is going to have to deal with this caustic liquid in addition to all the other stuff, and caustic liquids don’t make plumbers happy.

@crazyjoe: that was my understanding as well. I generally avoid Drano/Liquid Plumber and other chemicals you wouldn’t want to put your hands in.

Anyway, I used a wet/dry shop vac and sucked out the water after testing each time. I finally decided that I wasn’t going to get around disconnecting the drain hose from the disposal. I installed the disposal recently, so I was already familiar with how awful a job that would be (tight working area, right next to a corner, cabinet digging in your side, etc.).

As disgusting as this sounds, I tried to blow out the line myself to see if there was any resistance. I couldn’t blow it out. I don’t know if this was due to a check valve, a blockage or plain old air/water pressure physics. Regardless, the line (grossly) “burped” back at me with a dirty, grimy, watery mess. Yes, I got splashed all over my face & lips. No, you can’t have a kiss.

I then tried running the dishwasher through its fill/drain portions and had the drain line set in a bucket (actually the wet/dry vac’s catch). Water shot out like a rocket and the dishwasher drained. I repeated a few times, ran my finger & a paper towel through the connection to the garbage disposal, reconnected the line to the garbage disposal, and tested a few more times. It drained & there were no leaks.

Mission accomplished.

Now the question is, what did I really do to fix it? It’s a GE Potscrubber 940. It’s old. I’m guessing that there’s a check valve that was stuck partly open and me blowing in it caused whatever was stuck to unstick. There was no smoking gun of something stuck in the line, so I’m concerned that I’m going to get a call at work next week to hear that the dishwasher decided to water my floors again.

Ah! I see you also went to the TruAher school of home repair. . .

(Aher = Father)

It’s possible somethign was lodged in there and you dislodged it with your blowing. There is definitely a check valve at the dishwasher end of the pipe to prevent dirty water routing from your disposer to the dishwasher, and from preventing that last bit of pumped out water from going right back into the washer once the pump turns off (pumps can only push water, they don’t push air very well).

Congrats on your homemade repair. Sorry it was so disgusting.

I knew it was coming, but I couldn’t react quickly enough.

no no no no no no never use chemicals in a drain.

You probably had a block where the hose connected to the disposal. The blow back probvably moved and broke up the block.

That can’t be because I disconnected it at the disposal. However, it is possible to have been near that point and freed something up partly down the line. My old man is in the plumber & pipefitters union, though he’s a pipefitter. He thought it was probably a stuck check valve.

Anyway, hopefully I get a couple more years out of this one. We want to do a major kitchen remodel, but it’s financially impossible until both the market recovers and my children reach school age (so that my wife can go back to work).