Strange Kitchen Sink Problem

[bren99]

I have a double kitchen sink in my fifth wheel. If I run water in the sink it will not drain. I have let it sit a couple days and I look and the water is gone. If I run water again, it will not drain out. I have tried everything for sink clogs, used a snake and nothing happens or changes.

Has anyone run across this before? The sink is either clogged or it isn't, so why does it suddenly drain all the water out?

I need my sink back! Any ideas?

As a side note, my bathroom sink and shower drain fine.

[magic43]

bren99 wrote:
I have a double kitchen sink in my fifth wheel.

So does either sink drain, or neither? Do you have the "stopper" removed/loose in the sink that has no water in it? Each sink should vent through the other sink's open drain.

[ChrisMatthews]

I think for such issue calling drain cleaning service providers would be best option, as they they have full knowledge about the process and the problem. Many reputable businesses offer
drain cleaning service at very affordable prices. They may also help you with other problems other than a clogged sink.

[RV_daytrader]

BarneyS wrote:

bren99 wrote:
Am looking for the air admittance device. Not sure what I am looking for.

Air admittance valve.


Home Depot has them also.
Barney

Your P trap will connect to a vertical drain line...on top of that drain line is where the Air admittance valve usually is.

[BarneyS]

bren99 wrote:
Am looking for the air admittance device. Not sure what I am looking for.

Air admittance valve.


Home Depot has them also.
Barney

[bren99]

Am looking for the air admittance device. Not sure what I am looking for.

[greende]

So, did you ever look for an Air Admittance device under the sink as suggested previously? Usually in RVs they are black. It takes the place of the roof mounted vent. Sounds like it is sticking shut. Replacements can be found at Big Box or Ace Hardware.

[bren99]

Okay. I'm back. Thank you for all the ideas and posts. I don't have a sink roof vent. I had to get a friend to get up on the roof for me. I am unable to so that. So I was back to find more answers which I see I have gotten. I will continue to look for the vens ubder the sink. I have my gray tank open all the time and no, I don't have a galley gray tank, I checked.

[DReisinger]

I blew up the galley tank on mine, didn't realize the galley had it's own gray tank, expensive lesson

[Toolguy5]

Did it used to drain OK before?

Like others have said. Vent plugged or insufficient venting.
Does the galley have a separate gray tank that needs to be emptied?

[jamway]

Take your drain apart under the sink. Now you can clean all that junk out of the pipe and it will drain fine.

This is pretty easy to do and will fix your problem.

[Charlie_D_]

2oldman wrote:
How would you know it suddenly drains out unless you sit there and watch it? I must be missing something.

Mine drains about as fast as you add water. When removing drain plug it drains in a few seconds. No need to stand and watch it.

[dwayneb236]

So, if the galley tank is full as some suggest how and why would it eventually drain over night if there is no where for the water to go?

[rhagfo]

Mike Taverniti wrote:
Find your mechanical plumbing vent, usually at kitchen sink or bathroom sink. $ 6 at Lowes.
Problem solved

Halmfamily wrote:
If it's in an island there is an air vent under the sink. Remove that and see if it works. If it does go to Home Depot and purchase a new one. Good luck.

momentum rv wrote:
AAV (air admittance valve) under the sink if not working sink won't drain properly

^^^^^Check this first!

Except that you state it drains after a couple days. Do you have a separate Galley tank, have you drained it?

Last would be the roof vent, mostly blocked, (mud wasps).

[Memphisdoug]

Does the sink drain ok if you try slowly running water into it when empty vs. trying to drain a full sink full of water? That might help determine if it is a vent pipe problem. You say you took apart the drain pipe but did you try running a snake through the pipe and into the holding tank to see if there is a clog in the portion you did not take apart? Usually, about all you can take apart is the trap so that leaves a lot of pipe between there and the tank that could be clogged. If it is not clogged then it has to be a vent issue.