Kitchen Remodel double-sink disposal frustration

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maxrandb

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Recently remodeled kitchen. Double sink is deeper than old one. Of course, didn't think too lower the wall drain. Disposal outlet is 1/2 inch higher than wall drain, so that's good, however, only way to get trap connection was to reverse the P-Trap. Rise on discharge side of trap is 4 1/2 inch. Supposed to be no more than 4 inches.

Ran a dishwasher cycle and filled and emptied both sinks with no leaks, or slow draining.

Short of going into the wall to lower the wall drain, or eliminating the disposal, this seemed my only option.

Thoughts, recommendations?
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Breplum

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Using the p-trap in backward position, there will definitely be a tendency for crud to accumulate. I suggest a good basket strainer screen like OXO makes and try to virtually NEVER use your garbage disposal until you cut out the wall and lower the drain or remove the GD altogether.
Also FYI, connecting a dishwasher drain directly to a disposal or branch is not to code and a clear health hazard because it can back up directly into the dishwasher. That should be corrected and brought up to code with a DW airgap and proper sloped 7/8" drain hose. DIY is a hazard unless you understand plumbing codes and why they exist.
 

Jeff H Young

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should work , you might not keep a trap seal but it should drain. Id lower the trap arm or eliminate disposal
 

maxrandb

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should work , you might not keep a trap seal but it should drain. Id lower the trap arm or eliminate disposal
Thanks. It seems to hold a seal. I was looking for a low inlet P-Trap, but all I could find is the big box store version. I may make the long drive to the local plumbing supply store. I think a low inlet trap would allow me to lower the space between trap water level and the wall discharge. I am close. Rise should be 2-4 inches above trap water level and I am currently at 4.5.
 

maxrandb

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Using the p-trap in backward position, there will definitely be a tendency for crud to accumulate. I suggest a good basket strainer screen like OXO makes and try to virtually NEVER use your garbage disposal until you cut out the wall and lower the drain or remove the GD altogether.
Also FYI, connecting a dishwasher drain directly to a disposal or branch is not to code and a clear health hazard because it can back up directly into the dishwasher. That should be corrected and brought up to code with a DW airgap and proper sloped 7/8" drain hose. DIY is a hazard unless you understand plumbing codes and why they exist.
Thanks. I've got enough slack to put a high loop on the dishwasher discharge hose and will do that, and we never run the DW without running the GD first. New DW has an internal loop AG on supply side and check valve on discharge side to prevent backflow. I guess water would back up into the sink instead of the DW. In any event, if I need to, I'll lose the GD and just compost the scraps.
 

Jeff H Young

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maxrandb hasent shared which code is used in his area So I dont assume he needs an airgap a highloop might be fine
 

John Gayewski

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Thanks. I've got enough slack to put a high loop on the dishwasher discharge hose and will do that, and we never run the DW without running the GD first. New DW has an internal loop AG on supply side and check valve on discharge side to prevent backflow. I guess water would back up into the sink instead of the DW. In any event, if I need to, I'll lose the GD and just compost the scraps.
Internal loop air gap on the supply side? What does that mean?
 

maxrandb

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Internal loop air gap on the supply side? What does that mean?
I am not versed in the terminology, but, on my DW model, it's a loop on the supply that runs into a funnel on the back of the unit. Manual says it prevents dirty water from the DW cross contaminating the water supply, if the DW ever get backed up. There's also a check-valve on the discharge side that is supposed to ensure the discharge only flows one way. In my area, a high-loop under the sink is also acceptable. I have quite a few friends in my neighborhood and I have never seen a home with a DW air gap by the sink. Hope that helps explain what I was saying.
 

Jeff H Young

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I am not versed in the terminology, but, on my DW model, it's a loop on the supply that runs into a funnel on the back of the unit. Manual says it prevents dirty water from the DW cross contaminating the water supply, if the DW ever get backed up. There's also a check-valve on the discharge side that is supposed to ensure the discharge only flows one way. In my area, a high-loop under the sink is also acceptable. I have quite a few friends in my neighborhood and I have never seen a home with a DW air gap by the sink. Hope that helps explain what I was saying.
Yea wrong words thats all. A lot of people that arent in the trade dont know what a Airgap is . If you dont live in a area that has our Code (UPC) , California is about the only place I plumbed and 95 percent of homes have them and the rest are illegal
IPC My guess Is no one has them and why would they ? I do travel a little and never see them in Florida or other states that dont require, they meet , code
 

Reach4

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Internal loop air gap on the supply side? What does that mean?
I think that means there is a built-in air gap for filling the dishwasher from the potable plumbing, but there is no built-in air gap in the discharge path. They rely on a check valve to keep sink drainage from entering the dishwasher via the drain hose.
 

John Gayewski

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I think that means there is a built-in air gap for filling the dishwasher from the potable plumbing, but there is no built-in air gap in the discharge path. They rely on a check valve to keep sink drainage from entering the dishwasher via the drain hose.
There's no such thing unless they are talking about an Rpz. Or pressure vacuum breaker. Neither of those are very practical for a internal part. They would need serviced/tested regularly. A standard double check could be practical, but I've never heard of one on a dishwasher and they don't have an "airgap" which would be physical seperation from the house's potable water to the appliance, instead of a reduced pressure zone (maybe called an air gap, but it's definitely not) a double check would just malfunction and contaminate the water supply with no external clue to an observer.
 

Reach4

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Would you agree that your normal clothes washer has a supply air gap built in? They do not require an air gap at the standpipe.
 

John Gayewski

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Would you agree that your normal clothes washer has a supply air gap built in? They do not require an air gap at the standpipe.
They do not have a "supply air gap" built in. The main reason your house should have a backflow device is to protect the city from your house. Not to protect your house from itself. If someone was worried about supply water contamination they would need a proper testable backflow device at each hazzard.
 

Jeff H Young

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Would you agree that your normal clothes washer has a supply air gap built in? They do not require an air gap at the standpipe.
good question I would assume a washing machine gets a check valve of sorts in the water supplys to protect the home from dirty water getting into the potable water , never researched it but the appliance must have some official stamp . As for the drain needing to be protected from other dirty water getting in side evedently the brainiacs decided its not a concern getting poopy water on clean clothes as compared to getting it on clean dishes
 

John Gayewski

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A clothes washer is protected from the drainage, just like a dishwasher (or close), the drainage is air gapped. The part that isn't protected is the water supply. Like if some idiot wanted to use cyanide as a cleaning agent on his dishes. The chemicals haven't been seperated from the water with a backflow device. It sounds like whomever makes this dishwasher might be trying with some type of "air gap" but what I'm picturing could actually work, would be a very delicate balancing act between solonoids, regulators, cutoff switches, floats, and pumps. It could work, but I'd like to see it.

The city or municipality is responsible for their water supply it has been litagated all the way up to the supreme court. This is why many cities are moving to backflow devices being mandatory on houses as they have been in commercial settings for years. They cannot force a manufacturer (very easily) to start changing the way they manufacturer equipment.
 

Jeff H Young

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I dont think anything special about his dish washer no matter how the dishwasher is built if its certain codes it requires connection through an airgap if its in another code it never requires an airgap unless the high loop cant be made for some odd reason is how I understand.
this stuff gets political on how much bullit proof protection is needed. but yea just like 50 50 solder legal to make and sell or valves that arent "lead free" maybe there is some long term plan to completely phaze out use of certain things
 

John Gayewski

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I dont think anything special about his dish washer no matter how the dishwasher is built if its certain codes it requires connection through an airgap if its in another code it never requires an airgap unless the high loop cant be made for some odd reason is how I understand.
this stuff gets political on how much bullit proof protection is needed. but yea just like 50 50 solder legal to make and sell or valves that arent "lead free" maybe there is some long term plan to completely phaze out use of certain things
I'm not sure we're on the same page. Reach and I are talking about a supposed air gap on the water supply side of the dishwasher not the drainage. I'm saying a practical air gap on the water supply doesn't exist and his dishwasher apparently says it does.
 

maxrandb

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Update. Stress tested it least night with a spaghetti and meatballs dinner. The connection I thought would be the weak link, where the straight tailpipe enters the trap, I managed to find a straight pipe with a rim. Used a flat washer on the trap connection with teflon tape in them threads. Tightened it by hand, then just 1/4 turn with wrench. Something else will leak before that connection does. Anyway, draining on both sides of sink was fast, no water in GD, DW cycle drained like a charm.
I've got one of those old worklights our dad's all had, a light in a socket in a big metal cone. Shined it through the back of the trap, and it appears the water level on the right is slightly higher, maybe 1/4 inch.
I am not ripping the countertop and cabinet out to lower the arm. Maybe it can be done in place and from the crawl space, but for now, I will just keep an eye on it, and remove the GD if I have issues.
Thanks for listening.
 

Jeff H Young

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I'm not sure we're on the same page. Reach and I are talking about a supposed air gap on the water supply side of the dishwasher not the drainage. I'm saying a practical air gap on the water supply doesn't exist and his dishwasher apparently says it does.
Got it
 
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