I have 2 drains under my kitchen sink. Is this to code?

I am selling my house and the people buying our home had an inspector look over the house. He stated that our kitchen sink has 2 drain pipes and this is not code. He said sewer gas can back up in the one that has a trap that looks like an S. We have lived there for 10yrs and never had that problem.
Help.

If you can shoot us a picture that would help us better answer your question.

Here is a drawing of it. Sorry no artist

here is a drawing of it. This probably is original plumbing.
I hope this attachment works. The other pipe drains into the wall and then goes down to the main larger drain. Both drains coming together in the basement.

Yea an S trap is not legal at all. A plumber can fix this for you.

s trap

Can I do it myself?

Ok, sorry to highjack this a bit, but I am curious about this S trap.

My tub seems to be on this type of setup. It drains into a P trap, but in order to go around some obstacles an S trap occurred. The obstacles are now gone and it wouldn't be real hard to change from the S, but it seems to work and the trap, which has a cleanout, seems to hold water. Should I change it?? I have everything I need as I am doing some other plumbing connections.

I have attached a drawing in hopes of showing exactly what I have. If need be, I can supply a picture later.

The vent and main line are 4", the tub drain is 2" and is the only item draining into this vent. The tub drains quickly, but does have a gurgle as it's draining. Not sure if the gurgle is normal or not, it comes from the overflow tube. My last house had the gurgle, but I don't doubt it had vent issues.

Thanks for the help and sorry for the highjack....

I think the distance between the trap and that elbow might make a difference as to whether or not you actually have an "S" trap, but I am not sure about that.

That is an s-trap. You should change it while you have the chance. The fact that it is working doesn't mean anything; it still has the potential to siphon.

S trap

The configuration, not the distances, make it an "S" trap. But since there is no way for you to look down and see how much water is in the trap, how do you know it is working? As far as the sink drawing, I would wonder WHY someone would go to the trouble, time, and cost of doing it that way, when it is so simple to connect both sinks together and use the single "P" trap on the left.

Thanks for the replies about my tub, and again, sorry for the intrusion.

Assuming the distance from the (vertical) vent is not more than 8 feet, you are in business. Just reposition the 4 X 2 sanitee (cannot use a wye and 45, or combo) up a few inches to give 1/4 inch of grade per foot of horizontal run on the 2" trap arm to the trap. It will work great.

Many tubs and showers drain slow because they are run flat without grade or even slightly back-graded. It is also a good idea to support the trap arm just before the trap to ensure it has no way of slipping down the tailpiece from your tub and reducing or eliminating the grade.

Iduchen,

Cap off the s-trap and use one of these to tie the 2 sink drains together to drain into the p-trap...

sixlashes said:

Assuming the distance from the (vertical) vent is not more than 8 feet, you are in business. Just reposition the 4 X 2 sanitee (cannot use a wye and 45, or combo) up a few inches to give 1/4 inch of grade per foot of horizontal run on the 2" trap arm to the trap. It will work great.

Many tubs and showers drain slow because they are run flat without grade or even slightly back-graded. It is also a good idea to support the trap arm just before the trap to ensure it has no way of slipping down the tailpiece from your tub and reducing or eliminating the grade.

Click to expand...

I absolutely can't move the 4 x 2 sanitee, as this is just below where I had to support a 4" cast iron pipe, which is the vent for the system. I can however cut the line before the P trap and lengthen that. I would however have to use a 45 or a 90 to make the bend to the 4 x 2. Are you saying that won't work, it would not be a verticle connection, only horizontal. I can snap a pic if need be.