Kitchen sink not draining

[Shuff]

Bought a used 2015 Forest River Heritage Glen 356qb and started having trouble with the kitchen sink drain after about 1.5 months of use. During our ownership nothing has gone down the drain that could be questionable.

I’ve plunged it, drained all gray tanks, treated gray tanks. Pulled the p traps there’s nothing visible there when the pipes are dry. Tonight I tried unscrewing the AAV and water shot out of it while there was water in the sink..

What else can I do? Am I in over my head and need a professional?

 

[chrisski]

Take a look at the vents. I think one could be on the roof and could be clogged.

Have you tried putting any type of snake down the pipe to clear it up?

If practical, try parking on a hill so that it drains towards the grey water tank..

I have cut a hole in the plastic cardboard bottom, for a leaking tank repair, so I have some visual look at the pipes to the grey water tank. I can’t recall if the tank itself has a vent, but I know the vent pipe goes to the roof.

Others will have much better plumbing exp than I.

 

[dangerranger]

after the sink eventually drains you can snake the drain from the AAV to the holding tank. then run water down the sink to wash out the gunk.
sometimes just sitting a few months will let the debris in the pipe dry out and flake off the pipe to cause a clog. Good Luck DR

 

[glen1971]

Have you tried a new AAV? With a new valve, try snaking it like was previously mentioned, then flush with a sink or two full of hot water.

 

[5picker]

Have you inspected the drain piping from the bottom of the sink?
Do you have a conventional P-trap or do you have the HepvO trap?
Both can clog and give you issues draining.
Do not snake a HepvO trap. It has a plastic/rubber diaphragm inside that will be ruined by snaking the drain line.

 

[dangerranger]

Have you inspected the drain piping from the bottom of the sink?
Do you have a conventional P-trap or do you have the HepvO trap?
Both can clog and give you issues draining.
Do not snake a HepvO trap. It has a plastic/rubber diaphragm inside that will be ruined by snaking the drain line.

By snaking from the AAV he would be bypassing any traps. and since it had water at that point the clog is between the AAV and the grey tank. DR

 

[jimmoore13]

A word on snaking.

In many cases, what looks like schedule 40 (heavy duty) drain plumbing may be a thin-wall replica. I know this, because the drain pipe connecting my grey tank to the main dump is made of this thin-wall stuff. While the plastic is fairly durable, don't get too rambunctious with that snake.

It also seems reasonable to point out that a "blocked" vent is not likely to prevent draining altogether. Instead, water will drain and gurgle as air bubbles make their way up through the water as it drains. By all means, check and clean your vents (the "instavent" under the sink and the main vent from the grey tank through the roof. But no draining whatsoever suggests a clogged drain pipe. If you have the P-trap (or J-trap) off, you should be able to run a snake through the pipe.

BTW, if the main grey tank vent is clogged, the question is clogged with what? Could be a nest of some kind...perhaps yellow jackets. Take your time if you decide to snake the main vent.

One more word of caution. Get out your tape measure and do a crude measurement of the overall length between your starting point and where the grey tank is. Mark off that length with a wrap of masking tape on the snake. This way you know both when to stop and that you "got there" without having the business end of that snake, perhaps, tracing its way all the way down to the dump gate valve or curling up in the grey tank...and possibly damaging something. The ends of snakes are generally kind of sharp.

Lastly, my snake can be driven with a drill, and it has a lever to engage the snake spiral and move it forward or back. This is handy for making 90 degree turns and such. But be gentle with the power. Like I said, you may very well have thin-wall pipe, and these snakes are designed for schedule 40 or better plumbing.

 

[Aussieguy]

I would be taking the drain out from under the sink and clean it completely in a bucket hot water and soap


if it does not unscrew for cleaning
I would cut it off and install a P trap or whaterver I can make fit in that location

Local hardware will have all the parts you should need.
PVC glue and primer and if required rubber adapters you can put hose clamps on


before reassemble
use a hand operated snake down into the tank

find the vent and snake it too
--------------------------------------------------
If no big improvement in draining
get a endoscope camera attachment for your phone you might be able to spot the clog... use a plastic wrap to protect the little camera end

 

[Nhyrum]

I'd snake from the aav back, and the roof vent. To me it sounds like there is a clog or at least partial obstruction between the AAC and tank. If there's not much water volume moving, you don't have that large a demand for vent air.

As long as you have traditional p traps, you don't dump your grey water into a septic system, and you don't put it in the toilet, a sodium hydroxide based cleaner should do fine, just don't let it sit in the tank