Hi All

I have a very baffling situation. We changed our countertop, now the air-gap is overflowing for the first few seconds every time the dishwasher empties and makes a mess on the counter top, then continues to drain normally.

Here is the setup. THREE separate drains under the sink, each going into the wall: #1 for left sink, #2 for Right sink/disposal, and #3 dishwasher drain.

Dishwasher drain is a clear flex hose attached to the COPPER air gap, then a black rubber hose connecting the air gap directly to the drain going into a p-trap which then goes into the wall.

I have completely disassembled the entire dishwasher draining apparatus from washer to wall and the pipes are completely clean and free of any debris. With a flash light I can see all the way in to the wall drain which connects with the other 2 drains and this is also completely clean. Both sink bowls drain very nicely and efficiently.

I can not figure out why the dishwasher did not overflow before the new countertops, and now is overflowing. Any ideas?

Doc

Hi Doc,

Logic dictates that the pump is putting more volume then the system can carry away. This could be caused by a kink in the line downstream from the air gap to the trap. A restriction in the air gap it self or a partial blockage in the trap or drain line. Another possibility is the hose downstream from the might have a bell in it trapping some water. When the discharge from the gap hits it there's a momentary backpressure generated. This backs up the flow for a second spilling water on the countertop and then the backpressure's gone and it drains normally. While I can't pinpoint the problem I can point you to things that need to be checked. Good luck, Tom

Speedball

Thank you for such a prompt reply. That was quite a surprise.

Like I had said, there are no kinks that I can see, the inside of all the plumbing from the dishwasher to the waste line is easily visible and clean of any debris, including the inside of the air gap. The only thing that I can't verify 100% is what you said about the bell in the hose connecting the air-gap to the p-trap. I could see how that would cause a momentary backflow.

So what would you do to try to remedy this? I was thinking replace the black gap to trap hose first and see if that resolves it. What would YOU try first?

Thanks again,
Doc

And on a side note, is speedball what I think you're referring to or is it some kind of a game :D

Hey Doc,

"So what would you do to try to remedy this? I was thinking replace the black gap to trap hose first and see if that resolves it. What would YOU try first?"
If this were my call I'd remove the air gap and cover the hole with a
Chrome cock hole cover and run a "hose air gap". Because of problems we don't use air gaps in the Tampa Bay Area. We form a drip loop with the discharge hose. This is what you now have, (see image) We run the hose the same way except we don't install a air gap. The loop takes care of that. : Your drain hose MUST be looped higher then the flood rim what you are discharging into. All that means is when you run the line, strap it up so the loop is above the inlet of the disposal or whatever you are draining into. If this is not done the water that you discharge from the sink will drain back into your dishwasher. Iuse a 3/4" copper pipe strap to secure but a nail and some wire wil;l work also. Some models may have an outlet attached to the top, but most of them will have to be strapped up.
Replacing the air gap will most likely solve your problem but I thought I would give you some options.

"and on a side note, is speedball what I think you're referring to or is it some kind of a game "
Back in the sixtys I rode with a outlaw motorcycle club in Tampa. My club name was "Speed" since Speed was taken on the net and speedball1 wasn't I ended up with speedball1. I've tamed down since then. You can draw your own conclusions.
Regards, Tom