Sinks not draining/poor venting?

[buckarooman]

Two new under sink vents and it still is not draining my sinks, if I unscrew the air vent the sinks will suck down like a champ. I can't have a roof vent because I have a island sink, the only roof vent I've got is for the bathroom gray water tank and the black water tank, and there is only one vent but I don't have issues with the bathroom tank or the black tank. I'm at a loss, either my tank just is vented poorly and it's what I get to live with.

[buckarooman]

Got it! Finally just gave up on the aav and ditched it all together, I screwed a cap on to the pipe and drilled and tapped a 1/2 inch barb fitting. Then I ran a hose under the counters, then exited it out into the power cord box and silicone the heck out of it that's sealed back up. Then I kicked the hose and guess what the sink backs up, then unkinkrd it and what do you know it vents now to the out side! Like the dam thing should.

[Bowti]

With only one roof vent, it sounds like your three holding tank vents are plumped together. with your shower and black water drains working properly, I would guess the island sink holding tank vent is plugged before it joins the other tanks vents.

I don't know how you would be able to direct a hose to that specific area, but it may be worth a try. I'm thinking if you kept the shower and black tank valves closed. Then open the island sink tank drain, and run water down the roof vent and if water comes out of the holding tank it would tell you the vent is not clogged.

In doing this you are kind of running the risk of water backing up through the shower or bathroom sink drain if that vent is clogged.

[buckarooman]

Dano1955 wrote:

buckarooman wrote:

Bowti wrote:
Again, your AAV has nothing to do with venting your holding tank. You have people telling you your holding tank needs to be vented. Find the vent and make sure it is not plugged.

I realize that the aav doesn't any thing to do with the vent, I only have one roof vent and it's in the back of the trailer on the bathroom gray water tank. There's no physical way that the tanks are tied together the kitchen tank has only a aav an nothing more. The roof vent in the back vents the one gray tank and best I can tell the black tank, I can't see how they would have ran a vent line from the island sink to that roof vent with out it being under water.

Your island sink will be vented. Since there is only one roof vent, all the waste tanks should vent out to that single outlet

OK with that then how could the bathroom sinks and shower drain? If I shoved a hose down the roof vent would that clear the line? I guess I could do that and open bothbtanks and see if water comes out.

[Dano1955]

buckarooman wrote:

Bowti wrote:
Again, your AAV has nothing to do with venting your holding tank. You have people telling you your holding tank needs to be vented. Find the vent and make sure it is not plugged.

I realize that the aav doesn't any thing to do with the vent, I only have one roof vent and it's in the back of the trailer on the bathroom gray water tank. There's no physical way that the tanks are tied together the kitchen tank has only a aav an nothing more. The roof vent in the back vents the one gray tank and best I can tell the black tank, I can't see how they would have ran a vent line from the island sink to that roof vent with out it being under water.

Your island sink will be vented. Since there is only one roof vent, all the waste tanks should vent out to that single outlet

[buckarooman]

Bowti wrote:
Again, your AAV has nothing to do with venting your holding tank. You have people telling you your holding tank needs to be vented. Find the vent and make sure it is not plugged.

I realize that the aav doesn't any thing to do with the vent, I only have one roof vent and it's in the back of the trailer on the bathroom gray water tank. There's no physical way that the tanks are tied together the kitchen tank has only a aav an nothing more. The roof vent in the back vents the one gray tank and best I can tell the black tank, I can't see how they would have ran a vent line from the island sink to that roof vent with out it being under water.

[Bowti]

Again, your AAV has nothing to do with venting your holding tank. You have people telling you your holding tank needs to be vented. Find the vent and make sure it is not plugged.

[Joe_Way]

buckarooman wrote:


I wish I had a roof vent haha stupid island sink doesn't have one so the tanks only vented with the aav

In our trailer, the sink vents are separate from the tank vents. The tank can't vent properly through an under-sink vent. You might check on the roof for a vent in a location that makes it likely to be for the gray tank. Then see if the vent is clogged.

Joe

[momentum_rv]

buckarooman wrote:

Bowti wrote:
Not sure if you have found the problem yet, but from what you have posted so far it sounds like your holding tank vent is plugged. The Air Admittance Valve's only purpose is to keep your drain trap from being siphoned dry, which would allow fumes from your holding tank to stink up the place.

Your sink drains good with your tank drain valve open, and gives you problems with it shut so that points to your holding tank vent being plugged. This it what Old B was getting to.

Get on your roof and find out what pipe leads to the tank you are having problems with and unplug it.

I wish I had a roof vent haha stupid island sink doesn't have one so the tanks only vented with the aav

There has to be a way for air to get out of the tank. AAV allows air in but not out. Something is not right here.

[buckarooman]

Bowti wrote:
Not sure if you have found the problem yet, but from what you have posted so far it sounds like your holding tank vent is plugged. The Air Admittance Valve's only purpose is to keep your drain trap from being siphoned dry, which would allow fumes from your holding tank to stink up the place.

Your sink drains good with your tank drain valve open, and gives you problems with it shut so that points to your holding tank vent being plugged. This it what Old B was getting to.

Get on your roof and find out what pipe leads to the tank you are having problems with and unplug it.

I wish I had a roof vent haha stupid island sink doesn't have one so the tanks only vented with the aav

[Bowti]

Not sure if you have found the problem yet, but from what you have posted so far it sounds like your holding tank vent is plugged. The Air Admittance Valve's only purpose is to keep your drain trap from being siphoned dry, which would allow fumes from your holding tank to stink up the place.

Your sink drains good with your tank drain valve open, and gives you problems with it shut so that points to your holding tank vent being plugged. This it what Old B was getting to.

Get on your roof and find out what pipe leads to the tank you are having problems with and unplug it.

[buckarooman]

Wll I got about a quarter inch of silicone off the bottom of the pipe looks like from when they pushed it into the tank, I have ran a tape measure down the drain/vent pipe an there's no blockage. With the tank drain open the sink will drain like a champion with the tank closed it builds pressure again, only thing it could be now is I'm going to pick up some draino and wait till the sink backs up again and dump it down the drain to see if it clears the blockage. There also appears to be a smaller line or somthing in the middle of the tank that I can't reach after work I'm going go put the nozzle jet sprayer on and shoot it in the tank to see what that is I'm suspecting it's the level Guage but won't hurt to spray it down.

[buckarooman]

Now to figure out how to clean it, looks like they used a metric ton of putty and that is what the block is going to snake first and then use a coat hanger to dig on it from the outside

[wvcampers]

Sounds like you have found the problem

[buckarooman]

So i just went and looked my drain pipe is about a 1/4ich sticking through the top so it's not to far in, I'm going to get a snake and clean the pipe I'm thinking now it's maybe clogged were it enters the tank.