Kitchen sink problem


Old 12-10-02, 10:56 AM
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Kitchen sink problem

The kitchen sink was leaking when we moved into this house. I replaced it with a new stainless steel, 8" deep, double bowl sink. On top of the old sink, beside the faucet, was some sort of vent, a "breather" if you will. It was a mess, water sometimes coming up through it when the dishwasher discharged, so I left it out with the installation of the new sink. No problems yet.

Eventually, a year or so later, I replaced the old dishwasher with a new one. It made a horrible gurgling noise through the sink drain after discharging, seemed to be coming through the second bowl only. To stop this, I installed a p-trap under the second bowl, using it as a kind of muffler. The noise stopped.

Now though, both sinks drain slower than normal. Kicking on the waste disposal sends a temporary "surge" of water into the second bowl. Both bowls drain okay, they're not plugged.

I suspect I have an airflow problem. Perhaps I need to reinstall the "breather" on top of the sink. If I do though, how do I prevent it leaking water onto the counter when the dishwasher discharges? What is the breather for anyway? Shouldn't the sink be vented through the plumbing?

Many thanks in advance.
Old 12-10-02, 11:18 AM
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Dishwasher air gap

I never saw a dishwasher air gap until I moved to Kentucky. It was in a rental, and the darn thing spewed everywhere. The local plumber told me that air gaps are required by most codes for dishwashers and for water softeners. They are needed to prevent any possible cross-connection between your drinking water system and your sewage system. There is always a chance (however slim) of siphoning contaminants from your sewage system into your drinking water system.

My local plumber reported most people removed them when they start spewing. If you do, then strap the drain from dishwasher and hang it as high as possible inside the cabinet. Then, you plug the hole in the sink with one of those little stainless plugs.
Old 12-10-02, 11:58 AM
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air gap

Air gap, huh? So that's what it's called.

I've got the dishwasher drain hose looped up to the bottom of the sink before dropping back down to attach to the disposal. Everything worked fine that way until I added the p-trap to the second bowl. I suspect air was being drawn in through that bowl until it was closed with the p-trap.

I'm thinking I need to vent more air into the disposal, just to make everything drain quicker. Probably just removing the rubber diaphram in the sink would fix the problem, but that's neither safe nor very pretty.

Any one got any ideas or had this problem before?
Old 12-10-02, 06:58 PM
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I don't think your dishwasher has anything to do with your drainage problem--the air gap (either the one that came thru your sink, or the one that is created by having a loop in the drain hose) is there to keep water/waste from the disposer and sink from entering the DW. More likely, either your drain or vent for the sink is partially cloigged. At any rate the air gap for DW shouldn't affect sink/disposer drains.
Old 12-10-02, 09:37 PM
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Air gap

The kitchen bowl empties slower than what I consider to be normal. If the water is turned on full, it will only take about 30 seconds for it to start pooling in the bowl, it can't empty quick enough. However, if I take my hand and shove it into the rubber in-sink-erator diaphram in the bottom of the sink, opening the hole wider, the water drains immediately.

I'm thinking that since I added the p-trap to the second bowl, that part of the air supply has been cut off, making the bowls drain slower.

It's like taking a liter soft drink bottle, filling it with water, and then turning it upside down to drain. The water "gurgles" out because it has to make room for the air coming in. But if you were to poke another hole in the bottom of the liter bottle, the water would rush out.

I just don't know how I'm going to vent it so that it can drain quicker. Any ideas?
Old 12-10-02, 10:10 PM
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The drain line is plugging up, you need to get the line cleaned out, this will solve the problem.
Old 12-11-02, 07:55 PM
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Yeah, you need to just run a sink snake down the sink line... the double trap is unnecessary also... you dont need 2 traps under the sink... The sink does NOT vent through either side of the sink... it vents through a pipe in the wall... the whole purpose of the vent is to keep water in the traps, so it does not draw air through the traps... As to the air gap, you did the right thing getting rid of it... they do more harm than good in my opinion... and you did good by running the pipe up high enough to give the drain an airgap... When you disposal runs, it makes water briefly back up in the other bowl because it is ejecting the water faster than just running the sink... and that is the same reason you get all the gurgling when you run the dishwasher... it just runs more water out faster than the sink does... anyway, just unclog the drain and make sure you dont have any water going through 2 traps with the new one you added and you should be fine...
Old 12-13-02, 04:07 PM
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Kitchen sink problem

Thanks. I'll try some cleaner and see if I can open the pipes up any more than they are. They're not plugged, but they could have a bunch of gunk in them reducing throughput. I'll see what I can find that works with partial clogs.

Thanks again
Old 12-13-02, 07:31 PM
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Personally, I would invest $10 in a small drain snake and clean out the line with that rather than wasting the time and money on a chemical drain cleaner.

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