Trap 2-fer

[Bruce Ramsey]

Found a 2-fer today. Two P traps sharing a single vent under the kitchen sink AND an S trap in the master bath.

I guess you could call it a 3-fer since the dishwasher did not have a high loop before it emptied into the garbage disposal using the shared vent between the 2 P traps.

[Rick Cantrell]

I do not see a problem having two traps.

[James Duffin]

The trap in the third picture in the bath looks okay too. They used a P trap and PVC 90^. How else could it be done?

[John Goad]

With an aav so that it's vented.

[James Duffin]

Good point....

[Bruce Ramsey]

I do not see a problem having two traps.

The traps share a single vent. One could siphon the other dry.

[Jerry Peck]

I do not see a problem having two traps.

There are two trap arms shown, one from the vent out to the right and one from the vent out to the left, that is allowed.


The trap in the third picture in the bath looks okay too. They used a P trap and PVC 90^. How else could it be done?


With an aav so that it's vented.

The third photo is an 'S' trap and is not allowed, the easy correction is an AAV as John said (and James added as a "Good Point").

[mike huntzinger]

Disposal should have a air-gap device or high loop

[Mitchell Chiger]

With an aav so that it's vented.

Newbie question: What's an AAV? Thanks. Enjoy reading the forum.

[Paul Johnston]

Newbie question: What's an AAV? Thanks. Enjoy reading the forum.

Air Admittance Valve.

[John Arnold]

...The third photo is an 'S' trap and is not allowed, the easy correction is an AAV ....

If an AAV is allowed. They're not in Philadelphia.

[James Duffin]

In the third picture I was thinking the vent was not visible...like it was vented like an island sink would be.

[Rick Cantrell]

In the third picture I was thinking the vent was not visible...like it was vented like an island sink would be."

An island sink, like this one, should have a loop vent, however, in most areas an AAV is allowed.

[James Duffin]

I have seen wet venting allowed on island sinks but if the pipe is not sized properly it can siphon the trap.

[Bruce Ramsey]

In the third picture I was thinking the vent was not visible...like it was vented like an island sink would be."

An island sink, like this one, should have a loop vent, however, in most areas an AAV is allowed.

Not an island sink. Master bath sink as stated in original post. Located on second story with direct access to roof with no obstructions to prevent installation of a vent to the exterior. Master bath was an 2004 bump out addition to a 1971 split level.

[Rick Cantrell]

Maybe I was not very clear in my wording.
I should have said:
An island sink, as well as this one, should have a loop vent,...

[Jerry Peck]

In the third picture I was thinking the vent was not visible...like it was vented like an island sink would be.

Nope, that is a plain old (or new) 'S' trap.


I should have said:
An island sink, as well as this one, should have a loop vent,...

An island sink COULD have an AAV (where AAVs are allowed, which is most, but not all, places).

[Erby Crofutt]

Have it fixed by someone who not only understands drainage, but also venting.

Ya just gotta wonder sometimes.

[Bruce Ramsey]

100 yr old house coverted into apartment building. "Plumber" used the same technique in all 4 kitchens.

Two bowl kitchen sink. Individual traps on each bowl T'ed into a single pipe that goes down and and out but no vent. Do these become doubled S traps?

Since the two traps share a pipe before they exit and there is no visible vent, then this is not a valid configuration?

[Mitchell Chiger]

Air Admittance Valve.

Thanks, Paul.

[Rick Cantrell]

Bruce
Pics 1,2,&3, are S Traps. Pic 4, I cannot tell, it looks like ot goes into the wall, so it could be vented.