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 DWV fittings
Author: sum (FL)

I have a few questions about DWV fittings, not that I want to use them but just for my own understanding on their correct applications.

(1) Flexible fittings from Fernco, Zorro and other brands. They make sanitary tees, wyes, combos that are all rubber. I would imagine fittings like this would result in the piping being badly supported, and would be chewed up badly if it's snaked with a cutting head, and not code approved. Why are these fittings even made?



(2) "Simple" and "flexible" p-traps, that just seems like it's so clog prone for hair and kitchen waste. Why are these made? Is it only intended for some hail-mary emergencies? Yet I have seen these being used as a permanent drain installations in homes.



(3) Same question about bottle traps. Are bottle traps legal anywhere in the US? They are not cheap either, I have seen some that are $300+ in high end homes.



(4) Saddle fittings. I can see why saddle fittings are useful in irrigation where some seepage or leak is not the end of the world. What about DWV saddle fittings like this 4X2 saddle tee? When will someone use this? It does not have a sweep so this can't be a drain fitting right? So is this to add a 2" vent at the top side of a 4" horizontal pipe?



(5) A 90 elbow with a side inlet. The side inlet has no sweep to it, what can you connect to this side inlet? Can you connect a drain to it? A vent? Wet vent?





Edited 3 times.

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 Re: DWV fittings
Author: exapprentice30 (MA)

None of them fittings can used legally in my state and the side inlet 90 can only be used for a dry vent but I have seen them used for a wet vent in other states or if your replacing a side inlet 90.The rubber fitting would be the worst fitting to snake too. The saddle fitting is not legal too. I have seen a lot of drains drilled and tapped in to cast iron pipe too. Bottle traps are illegal too. The tube in the water can rot and let in sewer gasses but you would see water in the trap. The flex traps are paper thin and stuff can build up in them and clog.



Edited 4 times.

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 Re: DWV fittings
Author: PlumerDan (CA)

sum,back in the old days they made a 3 tee with 4 inlets then to top it off they 4 2in in between them .we called them octapuses.. somehow i just don't think there around any more.looking down on it you seen a 3x3x3x3 tee with a 2in.inlet between the 3in. take offs.
great for group bathrooms.

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 Re: DWV fittings
Author: bernabeu (SC)

for the same reason they make kerosene space heaters

someone will buy it

- - - -

Retired U.A. Local 1 & 638
"Measure Twice & Cut Once"



Edited 1 times.

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 Re: DWV fittings
Author: bsipps (PA)

The only legal fitting is the bottle trap it covers the 4” trap seal legality everything else is just an easy way out of a tight or not close installation

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 Re: DWV fittings
Author: sum (FL)

four inlets to one fitting? I have never seen such a fitting. Is it like a sanitary cross with two additional inlets?

I have also seen a sanitary tee with two inlets facing the same direction, like the eyes of an owl.

But I still do not understand what the intent of the side inlet to the elbow is. Is it for a drain or vent? It has no sweep to it.

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 Re: DWV fittings
Author: bernabeu (SC)

space - tight quarters

- - - -

Retired U.A. Local 1 & 638
"Measure Twice & Cut Once"

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 Re: DWV fittings
Author: vic (CA)

Sum, maybe it could used in some codes upside down in attics for combining vents together such as when having only one vent going through the roof?

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 Re: DWV fittings
Author: hj (AZ)

Actually EIGHT. The 2" openings were between the 3" ones. The modern "So-Vent" systems have fittings like that.

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 Re: DWV fittings
Author: LI Guy (IN)

Sum you forgot the "low heel inlet":



Apparently these are still code-legal if you use them with the 2" facing up for a vent connection. I found one in my old where the plumber used it in place of a closet bend to connect the sink and tub to the drain, and vent the toilet.



I wound up using the same fitting in PVC because I couldn't figure another way to connect the drains given the fixture placement and framing constraints. Lived there 5 years and it never clogged.....

- - - - - - -

Not a plumber by trade but a fierce DIYer



Edited 2 times.

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 Re: DWV fittings
Author: sum (FL)

so in that case the low heel inlet elbow was used to wet vent the toilet. I think I saw a variation of this fitting with the heel inlet is slightly higher I am not sure what it's called...high heel inlet?

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