Home Improvement Stack Exchange is a question and answer site for contractors and serious DIYers. It's 100% free, no registration required.

Sign up
Here's how it works:
  1. Anybody can ask a question
  2. Anybody can answer
  3. The best answers are voted up and rise to the top

We have a circa 1985 KitchenAid dishwasher and a Maytag batch disposer that may be from the same era. I had no doubt that the dishwasher turned on the disposer automatically when it was draining until the appliance installer came to our house and insisted that this isn't possible.

Is this an obsolete feature, or a kluge someone did when installing our appliances? Or am I just plain wrong? I did happen to see in this thread that the dishwasher has its own food grinder, which perhaps I have been mistaking for our disposer running?

share|improve this question

Some dishwashers have an internal food grinder, so there is no need to use an external one. It was common practice to connect the discharge of the dishwasher to the disposer, but not likely that the disposer would be activated by the dishwasher. In fact, it could be quite dangerous if the disposer was to activate automatically.

It's not impossible for the dishwasher to activate the disposer, but it's not likely (or common, or possibly even safe). You could verify whether or not the disposer is activated quite easily, simply by running the dishwasher and monitoring the disposer to see if it does indeed come on. There would also have to be some wiring running between the dishwasher and the disposer, so you could look to see if there is.

share|improve this answer
I'm not saying there doesn't exist a dishwasher with a internal food grinder, but I've never worked on one that had it. All I've seen is a plastic strainer/filter at the bottom and a standard discharge pump. – Jason Dec 2 '13 at 15:11
I'll check into it when we have our disposer repaired--it's broken now and probably just needs a new batch feed switch. It does seem a bit odd and certainly redundant if the dishwasher already has a grinder. However, while the disposer is broken, when the dishwasher drains, the sink "barfs" waste into the sink cavity. This seems to validate that the disposer does run during draining. – glenviewjeff Dec 3 '13 at 12:49
@glenviewjeff It's definitely possible, just not that common. Check for wiring linking the two appliances, or some type of switch on the disposer inlet. – Tester101 Dec 3 '13 at 12:55
From peeking under the sink and not disassembling anything, I didn't see any visible connections other than the power cord and the hose connecting the dishwasher drain. – glenviewjeff Dec 3 '13 at 15:57

Your Answer


By posting your answer, you agree to the privacy policy and terms of service.

Not the answer you're looking for? Browse other questions tagged or ask your own question.