what is this? troubleshooting a leak

[helios]

Hi all, new wannabe plumber here (and I say that with all due respect).

I am troubleshooting an issue, where occasionally, i will find a puddle in this cabinet and on the floor.

The puddle is occurring in the basement. The house has a main floor, and a second floor. There is a dishwasher, kitchen sink, and a full bath on the main level, and a full bath on the second level.

The question is, there is some sort of setup on the plumbing under the sink in the basement I've never seen before - There is an open notch on the vertical silver cap, the part in the middle between the j trap and the main.

Can I safely remove this setup or is it somehow necessary - otherwise, how should I attempt to fix the water from overflowing? I have attached some pictures. Thanks in advance -

 

[Matt30]

That's a non-approved, cheap, hardware store air admittance valve or "cheater vent". It allows your drain to suck air when you drain the sink because a proper vent is not present.

To get a code approved air admittance valve. Unscrew old, thread new in. Apply thread sealant.

For what it's worth, it's not installed correctly either. It should be as high under the cabinet as possible, behind the bowl of the sink. That's why now that it's failed, water is coming out.

 

[Debo22]

Time to also be a wannabe electrician and put that wire in a proper box

 

[helios]

That's a non-approved, cheap, hardware store air admittance valve or "cheater vent". It allows your drain to suck air when you drain the sink because a proper vent is not present.

To get a code approved air admittance valve. Unscrew old, thread new in. Apply thread sealant.

For what it's worth, it's not installed correctly either. It should be as high under the cabinet as possible, behind the bowl of the sink. That's why now that it's failed, water is coming out.

OK thanks - will get a new valve, and raise it up while I'm at it - thanks again

 

[helios]

Time to also be a wannabe electrician and put that wire in a proper box

Good point - thanks

I bought the house in this condition finding these little things here and there to correct

 

[Zanne]

Does the trap arm slope down at 1/4" per ft? I can't tell from the pic bc I know the angle is slightly askew (I have trouble getting pics that aren't askew myself). Maybe it's the angle of the photo, but it doesn't look like there is much downward slope (if any) on that pipe.

 

[helios]

Does the trap arm slope down at 1/4" per ft? I can't tell from the pic bc I know the angle is slightly askew (I have trouble getting pics that aren't askew myself). Maybe it's the angle of the photo, but it doesn't look like there is much downward slope (if any) on that pipe.

Hey Zanne - no, not much slope - should I create a downward angle to the main?

 

[CT-18]

If water is backing up high enough to come out the aav there might be a clog issue somewhere. The water in the drain should not be filling up to the aav.

 

[Zanne]

Hey Zanne - no, not much slope - should I create a downward angle to the main?

The proper slope required is 1/4" per ft drop. I think the pros here could help you figure out how to measure that to see if you have the proper slope. I still have not quite figured it out myself (well, at least not in such a small space).

Less than 1/4" per ft and the water will sit there- too much slope and the water will travel too fast and leave behind debris.

 

[pasadena_commut]

If water is backing up high enough to come out the aav there might be a clog issue somewhere. The water in the drain should not be filling up to the aav.

If there isn't a cleanout on the drain close to the left of the picture the OP might want to consider putting a small Y in to replace the horizontal element just to the right of the T for the air admittance valve. Of course with a cap on the upper part. Otherwise he's going to have to take some of that pipe apart to get a snake in each time it backs up. (The equivalent line on our house must be snaked about once every 3 years - luckily there is a cleanout just behind the sink.)

Is there a garbage disposal? It looks like no since that was probably what the power connection was for, and at least one wire is visible and capped. So maybe he could get a snake down from the sink and through the trap. Much easier to go in through a Y though.