Can I install a second trap?

[Artmg]

There is a 2"" pvc horizontal drain line in my basement that runs into a 4" drain going out to the septic system. The problem is that the line does not slope it is actually about 1" higher where it attaches to the 4". The line is about 8 feet long so if I were to cut the line I would be able to pull it down a bit but then it wouldn't line up with the 4" pipe. Can I attach another trap in line since there is already a P trap under the sink? Or is there another way get it to realign such as a 45 degree elbow. It drains alright but I'm sure that there is water always trapped in the lower end of the pipe. The only thing that drains into this line is the kitchen sink. I have attached a picture of the line as well as a picture of a trap in another line that I think would work . I have a sewer smell under the sink that I will ask about in a separate posting. Thanks

 

[Reach4]

How do the two pictures relate? I was thinking the left of the second picture fed into the left of the right picture. But since both have the basement wall in the background, that does not seem to make sense.

 

[Sponsor]

 

[Artmg]

They both go into the same 4" pipe but from different directions. Here is a picture of the whole setup. I put the picture of the trap in for an example of what I was thinking might be a way to adjust the height of the pipe so that I could lower it and reconnect to the 4" line . The trap is for the washing machine

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[hj]

A "second trap" is NEVER a good idea, and there is no way it could raise the connection point anyway.

 

[Reach4]

So the kitchen is off to the left of the new photo.

You are not supposed to run your softener drain in like that. I am not sure how much you want to fix things.

But anyway, what you would do is to cut the 3 inch near the left hand steel strap. You would get rid of the under-floor kitchen trap. You would come down from the sanitary tee under the kitchen sink, down to a long sweep elbow, to the 3-inch pvc that you just cut. You would make sure that your horizontal lines keep a 1/4 inch per foot slope. Add a new pipe support to make up for the one that is no longer in use.

The only kitchen p-trap goes into the side of the sanitary tee, and the vent connects to the top side of the sanitary tee.


So where do you route the softener drain? That could probably go thru the floor and join the washing machine drain with an air gap device that is made to share a washing machine drain.

Where does that dehumidifier drain to?