I have a condo unit built in the 1990s. The garbage disposal on/off will trip the circuit breaker every time it is turned on. The panel shows that the dishwasher and garbage share 2 15 Amp circuit breakers. In other words, 1 breaker controls the overhead microwave and disposal, the next breaker controls dishwasher and kitchen lights. (Sorry I’m not there at the moment so doing this from memory, not sure of the exact appliances labeled). The outlet underneath the sink is not GFCI and furthermore interestingly enough labeled with Dishwasher on the top three prong outlet and Disposal on the bottom 3 prong outlet. The garbage disposal works fine, nothing is stuck.
I bought a new plain old entry level GE dishwasher yesterday and connected it with a rated 13 amp plug bought from Home Depot. It’s hard to say if the outlet was working before, because the old tenant hadn’t used the old dishwasher for a few years, which I replaced because of the age. I’m going to suspect that the combo of the new dishwasher plug and old disposal has something to do with this issue. I also changed the underneath sink outlet with both a 20 amp GFCI outlet and a 15 amp GFCI outlet with no luck. I also changed the on off toggle switch for the garbage disposal, with no luck. If I plug the dishwasher into a different outlet, it works fine. The same with the garbage disposal, but of course I’m not able to toggle switch it to turn off.
I’m almost ready to hire an electrician but wanted to see if there’s anything else I can try.
I want to describe more in detail on the ordering of things:
The garbage disposal worked fine and we left it as is
we removed the dishwasher as it looked beat up. No idea if the old dishwasher was working previously.
we wired up a 13amp rated plug to the dishwasher. The dishwasher is a GE dishwasher: https://www.homedepot.com/p/GE-24-in-Stainless-Steel-Front-Control-Built-In-Tall-Tub-Dishwasher-with-Steam-Cleaning-and-52-dBA-GDF550PSRSS/318022460
Used this dishwasher plug to hook up to the dishwasher: https://www.homedepot.com/p/Everbilt-5-ft-4-in-16-3-3-Wire-Dishwasher-Power-Cord-Kit-98250/307638974
at this point we try plugging it into the free outlet (labeled “Dishwasher” on the outlet). This is a non-GFCI outlet. It did not work. We unplug the garbage disposal and plug the dishwasher in, and that works.
so at this point, we’re thinking that something is wrong with the outlet, and we replace it with a GFCI 20 amp outlet. Plugged both devices in and nothing works. Or the few times that it did work, the circuit breaker would break, especially after we tried to turn off the disposal. Furthermore setting the circuit breakers back to ON, the circuit breakers for the devices produces a blue or red flash color (if that means anything to you guys) most of the time at the circuit breaker panel. We try with a 15 amp GFCI, same thing.
6a) We then put in a new plain old outlet plug (not the original since the original used an old wiring scheme where the wires were put into holes rather than the newer method of wrap around). That seemed to work again with one appliance but not both.
we then tried plugging in a heavy duty extension cord coming from another outlet and then plugging in the appliances into this extension cord, and saw that the devices worked, so at least we knew it wasn’t the appliance itself.
we then tried to replace the disposal toggle switch, thing that maybe that was defective. Didn’t help. But it did help in the sense that at this point in time, we plugged both units back into the new non-GFCI outlet, and the Dishwasher works, the garbage disposal works, but the on off switch does NOT work - if I turn on or off the switch, the circuit breaks for both devices. And this is where we are at. So for practical purposes, the garbage disposal is not functioning the way it should, although I can manually plug and unplug the disposal under the sink if I really wanted it to function.