Dishwasher Drain Suggestons????

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Fraser Jim

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When I looked at the 10-year old plumbing for our sink / disposal / dishwasher, I realized that if the main drain line (either sink or dishwasher) backs-up, we are going to have water all over our hardwood floors.

Looks like they routed the dishwasher drain to open 1 1/2" PVC. Note that the PVC trap and pipe are glued into place.

Also, the sink has two sections. The disposal section is higher, so if it is full of water, it throws some into the main sink when first turned on.

I understand that our local code, Fraser Colorado, has changed and we don't need an air vent or open pipe.

I am looking for suggestions on the best way to seal up the dishwasher drain and fix disposal.

I was thinking of:

1. Cut off portion of 1 1/2" PVC, install fittings so that I can 1) route disposal over to PVC, 2) have "Y" for dishwasher drain, 3) cap off top of "Y" to seal, 4) have main sink drain dedicated to sink.

Only problem I see is if the glued "P" trap gets clogged.

2. Or, same but route dishwasher drain through disposal. Might be a tight fit because of sink, or I would need to swivel disposal for access.

3. Just figure out a way to seal top of PVC. Would still have disposal problem.

Suggestions?

Thanks!

photo.JPG
 

Terry

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I would go ahead and drain to the standpipe there. There are fittings that will reduce it down. When plumbers install them here, it's a 3/4" hose barb fitting. They still install them with an over the counter air-gap though.

The fitting into the disposer would need a 90 el to work.
The best method is an air gap above the countertop, but installing with a high loop is the next best thing.

I prefer running the disposer to a vertical tee on the other basket, but have also used a horizontal tee like on your picture.

sink_dw.jpg
 
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hj

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You have a Mickey Mouses sink/disposer drain and Mickey also installed the washer drain. You do NOT connect the dishwasher DIRECTLY to the waste system. Cap the riser and connect the DW hose to that "boss" on the side of the disposer, after you knock the plug out of the boss.
 

susan910910

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Sorry to resurrect an old thread, but I have this exact same crappy set up in my kitchen and I have a question that no one quite understands when I ask. Our house is 14 years old, and about 2 years ago our dishwasher just stopped working. We only used it about once a week anyway so it wasn't a big deal, we just hand wash the dishes. About 2 weeks ago we started smelling sewer gas in the kitchen, very obviously under the kitchen sink (not the drain or disposal) we cleaned out the garbage disposal, cleaned out all the existing pipes, made sure the p trap had water in it, checked the vent to the roof for obstructions and STILL had the smell. It got really bad the last few days, I was sitting on the floor staring at the plumbing this morning when I realized that the drain from the dishwasher has that large p trap shaped pipe (standpipe trap?) at the bottom and that it runs directly to the waste system, so I thought that if the p trap under the sink itself is supposed to have water in it to keep sewer gas out, maybe the water that was in the p trap shaped pipe that contains the dishwasher drain had enough water all this time that it was also blocking sewer gas since it is connected to the waste system, but when the water evaporated eventually (because we no longer use the dishwasher) it started to let gas in. I dumped some water in the top of the pipe and sure enough the smell immediately stopped. So, my questions is this, does what I said here make sense as far as sewer gas coming in to the cabinet from the top of the dishwasher drain pipe? I'm trying to explain this to the plumber that installed this mess before we moved in. If that didnt make sense, I apologize, I can be more specific if I need to be.
 
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Reach4

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I dumped some water in the top of the pipe and sure enough the smell immediately stopped. So, my questions is this, does what I said here make sense as far as sewer gas coming in to the cabinet from the top of the dishwasher drain pipe?
It's not as clear as you were hoping. A photo works wonders.

If you have a dishwasher that you never use, you should probably get it out. There could be stuff growing in there. If you do use it on occasion, try a cleaning cycle with a cup of laundry bleach instead of detergent.

If you have two standpipes with two traps, they both need to have water in the traps. If you have a separated dishwasher trap that is not being used, you could block the hole with a suitable stopper. Alternatively, you could add a pint of water to the unused trap every week if you are in the dry part of AZ.
 

susan910910

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It's not as clear as you were hoping. A photo works wonders.

If you have a dishwasher that you never use, you should probably get it out. There could be stuff growing in there. If you do use it on occasion, try a cleaning cycle with a cup of laundry bleach instead of detergent.

If you have two standpipes with two traps, they both need to have water in the traps. If you have a separated dishwasher trap that is not being used, you could block the hole with a suitable stopper. Alternatively, you could add a pint of water to the unused trap every week if you are in the dry part of AZ.
Sorry, that's what I was afraid of, lol. Here is a picture. Pipe A and Pipe B connect together with a p trap that I had just taken off when this picture was taken, there was water in that, it is the trap for the sink and the garbage disposal. Pipe C is what I think is called a standpipe with a p trap? That pipe has the drain from the dishwasher at the very top of it, and is open aside from the copper drain tubing. What I'm wondering is if the p trap at the bottom of pipe c didnt have any water in it, is possible that sewer gas was coming in through that pipe seeing as both pipe A/B and pipe c all drain in to the same pipe in the wall at the same place? I know I sound like an idiot here, but I am not a plumber by any stretch of the imagination. =)
 

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