Need help connecting disposal to main drain

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snrusnak

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Hi all,
First of all, sorry I'm not doing a lot of digging, I'm sure this has been discussed. I'm moving right now while at the same time finishing remodeling our house to put it on the market. Life is BUSY lol.

I'll make this short and simple, see the attached pic. I didn't know how to get the trap to the main drain as it's about 1" too low and I can't adjust it any higher. It's also about 1/2" too far as in the drain needs to be slightly closer to the disposal.

Any help on how to correct this is appreciated!

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The flex pipe keeps leaking right where it meets the trap. I've concluded it's not designed to hold water...
 
Wait.. so the waste is supposed to flow out of the disposal and then in to the flex pipe and go up in to the main drain?

If that is what is happening then that probably explains why there is a leak. Water drains by gravity. The purpose of the trap is to hold water to prevent sewer gases from coming up. After that you need to have the pipe go downward at 1/4" slope per foot to tie in to the drain. So you need to find a way to move it down, not up.

I've been told here that flex pipe is not very good to use in general, but having it on a garbage disposal is really not a good idea because it will likely catch the gunk that goes through it.

Is it the drain for a sink that it is tying in to? I can't really tell. Maybe you can lower the height of whatever it is connecting to so that you can have it go at a slightly downward slope.

http://www.ashireporter.org/HomeIns...sposals-Misused-and-Improperly-Installed/2494 shows some common mistakes when installing a garbage disposal unit.

Here is an example of how a double sink with disposal is plumbed:
garbagedisposal.jpg


Flex pipe is not approved for use by UPC, if I recall correctly.

(I'm not a plumber, just a DIYer who has been studying the plumbing code and trying to learn from the pros here).
 
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thx for the response. We used to have a double sink, now have a single. The disposal was on one sink and the other was just a regular drain. They had separate drains that dumped in to a 4" (I think) main drain. See pics.

I don't like flex pipes, but didn't know what else to try. I just realized what happened and why the issue is now occurring. The new sink is deeper, which places the disposal lower.


As you can see, there's really no way I can cut in to the pvc to lower the drain. The trap exit is maybe 1" too low for the main drain. There's no way I can redo the main drain right now. Is there a way to extend the mid joint of the trap by about 1"? That's the only think I could see working. Or a disposal exit that doesn't go down so low? I'm at a loss of how to fix this...

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I can't see for certain from the photos, but you are real close to the point that the grinding chamber is going to hold water, causing odors and premature failure of the disposal. The drain needs to be lowered. It is a doable thing, but not an easy DIY task. I would recommend some professional help with this one.
 
Thanks phish. Can you elaborate on how to go about lowering that Pvc drain? I've worked a lot with PVC, my father had a pool plumbing business. But we never did renovation work like this. there's no way that I see to do it from what I know seeing as the only thing there is the fittings and no bare pipe.

I wouldn't mind calling a plumber either. But I'm listing the house for sale Friday. Any hint on what this might cost me? My backup plan is remove the disposal and instal a regular drain. The disposal is an old one that I'm reusing so I don't feel to bad about it although I'd like it installed.

Sry about grammar, I'm on the cell phone
 
You will have to cut pipe below cabinet becausenall the fittings are hub to hub. You need to find some pipe to work with
 
ok thanks.

Let me ask this, are all disposals the same dimensions? Is there a chance I could buy a new one that would have an exit up higher?

If that won't work I think I'm just going to install a regular drain and eliminate the disposal. I'm moving out of the house today and don't have any more time. I assume they make a regular drain with a fitting for the dishwasher, correct? (I've never hooked one up without a disposal)

Thanks all.
 
I've come to the conclusion that I won't be able to get a new disposal with a higher discharge height, as usually the smaller the disposal the lower the hp. And I have a 1/3 hp. Not having the time to get a plumber in here and not wanting to spend that money(I assume this will be pricey) since I'm moving out today, I think my best option is to delete the disposal, install a regular drain, and leave the wiring terminated to an electrical box under the sink with the wires capped off. I can tell whoever buys the house the drain will need lowered if a disposal is to be installed.

I really wish I was aware of this before getting a deeper sink.... oh well live and learn.

They do make a regular sink drain with a disposal hook up, correct?
 
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I thought I'd put a tape on it to show the situation more clearly...

You can see the trap exit needs to raise about 1-1.5". The disposal discharge pipe is currently bottomed out in the trap, but even if I cut down the discharge pipe I can't gain 1.5". I can MAYBE gain 1".

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I know that some models come with a pipe that exits out that goes straight instead of bending down. My Insinkerator Evolution 3/4hp compact model came with a downward pipe and a straight pipe that can be sawed down. I'm not sure if that helps you any.
 
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Thanks man.

I just threw a regular old drain in it. Anybody have issues with this or is it all good?

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lol my thoughts exactly...

well it leaked then leaked again and 3rd time's a charm I guess. I dunno why but it was leaking at the first joint after the trap. Seems fine now. Maybe there was a nick in the washer.
 
Seems fine now. Thanks all.

My house is about 99.9% empty lol. Just in the nick of time. Cleaners come tomorrow, I'm glad we aren't doing it as we have run out of time. I move saturday...
 
Oh yeah, I'm sure I'll have leaks at my new place :)

I'm renting for 6 months then planning on buying. So might not be on much for 6 months or so but after that sure will!
 
We've had 3 offers on the house in a week! Supposedly another coming in this weekend! The upgrades were well worth it, we are in pretty good position right now. And for more than the asking price too.

Happy 4th! Be safe.
 
We've had 3 offers on the house in a week! Supposedly another coming in this weekend! The upgrades were well worth it, we are in pretty good position right now. And for more than the asking price too.

Happy 4th! Be safe.

Excellent news! Hopefully you'll get a good price!
 

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