air gap overflow

[Mark Moasser]

I just moved into a brand new apartment in a brand new hi-rise building. I had the kitchen countertop and sink re-done. I have a Bosch dishwasher and the drain hose goes into the side smaller inlet of an airgap and a thick black tube goes from the larger port of the air gap to the top of the disposal. I used it for the first time today, and after running for a while, when it got to draining, all of a sudden a lot of water started shooting out of the airgap all over the countertop and the floor.

What's the problem here? I doubt it's a clogging issue cause all the tubes and pipes are brand new and the sink drains very well. I turned on the water valve to the dishwasher one and a half rotations, perhaps it's too much pressure? Are the connections to the airgap and the diposal done incorrectly? It seems to be correct according to the Bosch installation manual. Any help would be appreciate cause I am clueless!!

Frankly, given the shape of an airgap I am not surprised that the pressurized drainage shoots out the top rather than turn around and go down, so I don't really understand how an airgap is supposed to function.

Thanks
Mark

[Clayton]

Since this is all brand new, I will take a guess and say the installer probly forgot to knock the plug out of the side of the garbage disposal before connecting the hose to it. So there is some kind of clog, wether it be the airgap itself or between it and the connection to the garbage disposal.

The amount you turn on your water valve should have nothing to do with how fast it drains only how fast it fills up. There is a pump built into the dishwasher to discharge the dirty water.

EDIT: If the problem is that the plug from the disposal wasn't removed... just disconnect the hose (use something to catch the water) and insert a skinny flat screw driver into the barbed nipple and tap around the edges to break the plastic plug out. Be careful as not to get too rough and create drainage leaks. Oh,, unplug the electric to the disposal first, and when finished reach inside to remove the plastic plug or it could jam the disposal.

good luck

[hj]

It will overflow if the plug is not removed from the disposer, but also if the large rubber hose is not as short as possible, with no "dips" in it.

If you run the dishwasher into a disposer, make sure the plug is knocked out first in the disposer. The waste can't enter the disposer if you haven't knocked out the plug inside the inlet.

[jimbo]

Plastic plug is the most likely answer. (" I don't need to read no stinking instructions!"). BTW Insinkerator specifies in their instructions that it is OK to leave the plug in the disposal and let it grind up.

I have seen problems with the Bosch. Apparently it has a very strong pump. If the line down from the air gap is not "perfect" you can have backup problems.

[master plumber mark]

the air gap itself might be the problem...
something might be stuck in it , it just might be old and worn out too.

depending on where you live in the country,
many places dont even require this air gap
I have always considered it total overkill...


In teh midwest, all they require is to run
the hose as high as possible under the sink
then hang it firmly with a clamp or wire..
then loop the hose back down to the disposal.

it works exactly like an air gap , i
t is an air gap without a mechanical part that fail.

for about 1.5 million homes in my area its done this way with never any problems to speak of.

[hj]

I don't know where that recommendation is, but it would either jam the disposer or make a horrendous racket until it was ground up.

[jimbo]

hj, it is a small plug, not much bigger or thicker than a nickle, and it does grind away quickly.

[Deb]

I have seen them jam disposers. I would never leave one in.
Deb
The Pipewench

[hj]

I installed an ISE yesterday and for the first time in decades read the instructions to see about the plug. It says in capital letters, and we all know what that means don't we?, TO BE SURE TO REMOVE THE LOOSE PLUG FROM THE DISPOSER.

[Mark Moasser]

OK guys. I checked it out and it is NOT the plug in the side of the disposal. The side port of the disposal is patent. I also checked and the thick black tube from the airgap going to the diposal drains well and is fully patent. I thought perhaps it was a bit too long, so I shortened it as much as possible and re-attached. I tried the dishwasher again and still, when it comes to draining, the hot water shoots out of the airgap all over the countertop and the floor.

I don't really know much about plumbing, or about how an airgap is supposed to function. But looking at this thing shooting out water, I really do not see how it can possibly work. With the cap off the air gap I got a good glimpse of the water shooting out and it was a solid jet going up a foot into the air. Considering the force with which the drainage comes, I can't possibly imagine it flowing back down the airgap drain by gravity without coming out the side holes. As I said, I am not a plumber, but how the hell is an airgap supposed to work????? It makes no sense to me.

Is it possible that the dishwasher is draining out with too much force? Can the force of the pump on the dishwasher be adjusted? I don't see any adjustments on this. It's a Bosch SHX33A.

Thanks for any help
Mark

[Mark Moasser]

Oh, and one more question:

Is my air gap linked correctly?? The way it is right now, the draining tube from the dishwasher goes into the smaller inlet in the airgap, and it is connected to the central barrel that goes to the very top of the air gap and is open to air (at the roof). The hose from the disposal connects to the bigger inlet in the air gap which is connected to the outer rim on the top of the air gap. Is this correct, or should it be swapped?

Thanks
Mark

[Terry]

The hose from the dishwasher goes on the small pipe,
The hose to the disposer goes to the larger end.

[Mark Moasser]

I'm still hoping someone can help me please. It's all detailed above. My airgap overflows badly when the dishwasher drains. The hookup is right and everything is patent, no blocks. I suspect it's a pressure issue. Can a dishwasher be too powerful for an airgap?

Thanks for any help
Mark

[Terry]

There are good air gaps and bad ones.

I use the "Dearborn Brass" ones.
The plastic dome below the chrome cap is rounded.

The air gaps I dont like are flat across the top.

Beware of the Costco Titan disposer, the dishwasher inlet is undersized.

[hj]

I don't know what you mean when you say the drain opening and drain hose are "patent", but you could not reverse the connections, because there is no way you could have a flood of water coming out of the bottom of the air gap and expect it to enter that small pipe. If the drain hose from the air gap is installed proper, i.e., as short and direct as possible with no sags, it will accept the flow from the small pipe without overflowing. Why yours does not may be something that can only be diagnosed by checking it. Why isn't the plumber who installed it being asked to check it out?