Sludge prevention?

[Jack.Straw]

Hi guys. We have this double sink in our kitchen. About every 2-3 months I have to take the thing apart and clean it out because sludge builds up and starts to stink up the kitchen. I've tried things like Draino, but that doesn't seem to do the trick, so I just keep taking the whole thing apart, blasting out the build-up outside with a hose, and using a big bottle brush with bleach in the slop sink to remove the rest and kill the bacteria. I hate doing this and would like to find an actual solution.





When I look at the way the contractor installed the pipes, it occurs to me that maybe this is happening because there is no tilt/angle to the pipe coming from the left sink. That is where the sludge build-up happens. Is the solution to add a peice below the right sink to drop down the trap and create a slope coming from the left sink drain, and then add the same size peice back behind the trap to bring the pipe that goes into the wall back up to level with the opening? Or, is there a product that I can use that will actually remove the sludge and smell? Thank you for any advice you can offer.

 

[Twowaxhack]

If you put the stoppers in each side of the sink and fill the bowls up to the top and then pull the stoppers, how long does it take the bowls to drain ? Do they create a vortex ? Can you hear the bowls draining ?

If they’re draining slow, then that can be a problem.

If you use a high liquid soap to water ratio that can be a problem.

Not running enough water can be a problem.

I see a DIY job on the horizontal piping under your sink and you may not have a high loop/air gap on the dishwasher hose. But I doubt those issues are causing the majority of your problem.

 

[MicEd69]

The slope required is only 1/4" per foot, so you may not be able to see that. But if that dishwasher tailpiece that is installed on its back, which is not the correct orientation of a tailpiece, that baffle could be restricting flow from the left sink allowing crud to lay in the pipe. Here's a picture of a baffled tailpiece.

 

[Jack.Straw]

The slope required is only 1/4" per foot, so you may not be able to see that. But if that dishwasher tailpiece that is installed on its back, which is not the correct orientation of a tailpiece, that baffle could be restricting flow from the left sink allowing crud to lay in the pipe. Here's a picture of a baffled tailpiece.

View attachment 41888

View attachment 41889

Thanks! I do recall seeing that baffle when i'm cleaning the pipes. You can see in the picture the current orientation of the dishwasher attachment part, and it seems like form the picture that it dictates the orientation of the baffle. Is that a correct assumption? What orientation should it be in?

 

[Jack.Straw]

If you put the stoppers in each side of the sink and fill the bowls up to the top and then pull the stoppers, how long does it take the bowls to drain ? Do they create a vortex ? Can you hear the bowls draining ?

If they’re draining slow, then that can be a problem.

If you use a high liquid soap to water ratio that can be a problem.

Not running enough water can be a problem.

I see a DIY job on the horizontal piping under your sink and you may not have a high loop/air gap on the dishwasher hose. But I doubt those issues are causing the majority of your problem.

I actually only have 1 stopper, so i can't test both sinks at the same time. I will say that both sides of the sink get used quite often, on a daily basis, and that neither has any slow drain issues that I can tell. It's fairly rare that we use liquid soap; most things go through the dishwasher. The dishwasher soap we use isn't consistent, but it's always some kind of pod.

 

[Twowaxhack]

I actually only have 1 stopper, so i can't test both sinks at the same time. I will say that both sides of the sink get used quite often, on a daily basis, and that neither has any slow drain issues that I can tell. It's fairly rare that we use liquid soap; most things go through the dishwasher. The dishwasher soap we use isn't consistent, but it's always some kind of pod.

Get creative and find a way to fill both sink bowls up and see how fast they drain when you pull both stoppers.

I suspect the drain is slow and that’s causing build up in the piping.

 

[MicEd69]

Thanks! I do recall seeing that baffle when i'm cleaning the pipes. You can see in the picture the current orientation of the dishwasher attachment part, and it seems like form the picture that it dictates the orientation of the baffle. Is that a correct assumption? What orientation should it be in?

They are usually installed in the vertical position like below.



And your existing inlet appears to be more of a right angle than the one in the picture above. With a steeper angle on the dishwasher inlet and one without a baffle, the dishwasher flow will provide a better scrubbing effect on the drain pipe.

 

[Aggie83]

They are usually installed in the vertical position like below.

View attachment 41893

And your existing inlet appears to be more of a right angle than the one in the picture above. With a steeper angle on the dishwasher inlet and one without a baffle, the dishwasher flow will provide a better scrubbing effect on the drain pipe.

That height under the sink seems very short. Do t see where to add that piece.

 

[Mitchell-DIY-Guy]

@MicEd69 had it correct: the dishwasher tailpiece must be installed vertically.

That sink doesn’t look any deeper than my deep sink yet there’s no apparent vertical space left underneath, to the point where you need a cut-out to install the trap. What am I missing? Is this a special low height cabinet?

You can buy new drain covers and strainers anywhere..

 

[sawguy]

@MicEd69 had it correct: the dishwasher tailpiece must be installed vertically.

That sink doesn’t look any deeper than my deep sink yet there’s no apparent vertical space left underneath, to the point where you need a cut-out to install the trap. What am I missing? Is this a special low height cabinet?

You can buy new drain covers and strainers anywhere..

That's a shelf under the sink, not the cabinet bottom.

 

[Twowaxhack]

The dishwasher tailpiece does not have to be installed vertically.

 

[Mitchell-DIY-Guy]

…and yet the sludge builds up.

The guy is asking for help. Remove the shelf and plumb it correctly! Install the baffled tail piece vertically as it is supposed to. Add a high loop or air gap for dishwasher drain line. Regardless of any hidden behind the wall vent, add an AAV. That’s the way a licensed master plumber here would do it. Do it correctly by removing the shelf, and you won’t be disassembling the plumbing periodically for cleaning.

When all is said and done, if there’s and room, add any convenience shelving.

 

[Twowaxhack]

There’s no vertical space because the drain coming out of the wall is roughed in too high. Removing shelving doesn’t correct the high rough in.

But dishwasher tees do not have to be installed vertically. I’ve installed hundreds and there’s no sludge being built up. That’s from the USER not running enough water or the drain being partially clogged down the line.

But if the OP wants a vertical inlet for the dishwasher they can install this.

https://www.supplyhouse.com/Sioux-C...MIw9rb-K7_gAMVszLUAR2o6AqMEAQYCCABEgIoFfD_BwE
But when I find build up inside sink drains it’s from lack of a sufficient volume of water being used or drain is very slow due to needing a good cabling, or both.

Happy Monday everyone

 

[MicEd69]

…and yet the sludge builds up.

The guy is asking for help. Remove the shelf and plumb it correctly! Install the baffled tail piece vertically as it is supposed to. Add a high loop or air gap for dishwasher drain line. Regardless of any hidden behind the wall vent, add an AAV. That’s the way a licensed master plumber here would do it. Do it correctly by removing the shelf, and you won’t be disassembling the plumbing periodically for cleaning.

When all is said and done, if there’s and room, add any convenience shelving.

That is the best answer to fix this ongoing problem.

With a baffled tee on its back, you basically have the flow area of a 1/2" pipe instead of the 1 1/2" drain line used for a sink. Used in the vertical position, gravity allows that smaller drain area to work, and it only slows the flow from the drain. In the horizontal position, it;s like having a built-in blockage of half the pipe.

 

[Jack.Straw]

Thanks guys. I appreciate the help. Removing the shelf isn't ideal, as it isn't a matter of just taking it out. It's actually built into the unit, instead of just resting on pegs or something. You can see where the contractor cut a chunk of the shelf out to make room for the trap. The other thing that may or may not be an issue with this solution is the location of the pipe in the wall where these drains connect. If I were to remove the shelf and lower the pipes down to create enough space for the dishwasher tailpiece to be installed vertically, i would have to add vertical piping after the trap to bring the final run up to the same level as the hole in the wall. Again, i'm not sure if that's actually an issue... it's just that i've always seen a 90 after the trap in my limited experience.

Is there a product that I could put down the drain on occasion that would dissolve the sludge or prevent build up? While i would prefer a permanent solution, I would also prefer not to have to cut out that shelf out with a saw.

 

[Twowaxhack]

Thanks guys. I appreciate the help. Removing the shelf isn't ideal, as it isn't a matter of just taking it out. It's actually built into the unit, instead of just resting on pegs or something. You can see where the contractor cut a chunk of the shelf out to make room for the trap. The other thing that may or may not be an issue with this solution is the location of the pipe in the wall where these drains connect. If I were to remove the shelf and lower the pipes down to create enough space for the dishwasher tailpiece to be installed vertically, i would have to add vertical piping after the trap to bring the final run up to the same level as the hole in the wall. Again, i'm not sure if that's actually an issue... it's just that i've always seen a 90 after the trap in my limited experience.

Is there a product that I could put down the drain on occasion that would dissolve the sludge or prevent build up? While i would prefer a permanent solution, I would also prefer not to have to cut out that shelf out with a saw.

Yes, that product is hot water. Fill the sink bowls up and flush the drain with hot water weekly. If the drain down the line is free and clear your problems will resolve.

Run plenty of fresh hot water.

Removing shelving won’t help anything, shelving doesn’t hurt drainage

 

[MicEd69]

The piping that Twowaxhack had a link on, https://www.supplyhouse.com/Sioux-C...MIw9rb-K7_gAMVszLUAR2o6AqMEAQYCCABEgIoFfD_BwE, would be the best solution. You cannot raise the P-trap outlet, or you will flood your drain lines going into the P-trap leaving them full of wastewater.

 

[Jack.Straw]

There’s no vertical space because the drain coming out of the wall is roughed in too high. Removing shelving doesn’t correct the high rough in.

But dishwasher tees do not have to be installed vertically. I’ve installed hundreds and there’s no sludge being built up. That’s from the USER not running enough water or the drain being partially clogged down the line.

But if the OP wants a vertical inlet for the dishwasher they can install this.

https://www.supplyhouse.com/Sioux-C...MIw9rb-K7_gAMVszLUAR2o6AqMEAQYCCABEgIoFfD_BwE
But when I find build up inside sink drains it’s from lack of a sufficient volume of water being used or drain is very slow due to needing a good cabling, or both.

Happy Monday everyone

TWH, the volume of water being run isn't likely to change. The sinks drain faster than the maximum faucet speed, so filling the bowls and letting them drain isn't going to tell us anything, right? It is extremely rare for us to fill the sink with water, so it's only ever going to be the water coming directly from the faucet, or perhaps that rate plus some amount of water that was in a a dish that i dump out at the same time. If increasing the amount of water flowing through the pipe is the solution, could it make sense to move the dishwasher tailpiece further up the line toward the left sink drain? That would force all the water drained from the dishwasher to move through more of the pipe. If i remember correctly, the sludge build up is before the dishwasher tailpiece.

 

[Jack.Straw]

Yes, that product is hot water. Fill the sink bowls up and flush the drain with hot water weekly. If the drain down the line is free and clear your problems will resolve.

Run plenty of fresh hot water.

Removing shelving won’t help anything, shelving doesn’t hurt drainage

I see. I will try this, but doing this weekly isn't ideal for my personality haha. I will try though. I'll do the 1st one today and let you know how fast it drains. Thanks!

 

[Twowaxhack]

After you wash dishes with the dishwasher you should flush the drain clean with fresh water. Don’t let that water sit in the trap and sour.