another black tank question

blue eyes · 08-15-2010, 08:28 PM

We are having all kinds of trouble with smell from the black tank, we have installed an electric fan to the vent pipe that is supposed to pull the smell out, however, when we were on the roof this weekend inspecting things, we were puzzled as to why we couldnt smell anything being pulled out through the pipe, we removed the fan, to make sure that it was working and moving in the correct position and all was fine. We then removed the entire fan and didnt get any smell coming out the vent. Shouldnt there be?
The smell was so bad in the trailer when we opened up and flushed for the first time that I thought I would die. As I posted previously, we are on a permanent site, so we dont have the luxury of being able to add all kinds of recommended items and let it sloosh around for awhile.We cant get the trailer to the dump station, so we have to rely on many trips there with blue tank in tow. We have it pumped out every other weekend hoping that just filling it full with water would somehow help to get it completely flushed.
Could there be a venting problem here that we are overlooking? The smell is only in the bathroom, nowhere else. I have tried everything that has been mentioned and still no success. Also, we measured the vent pipe and it is approximately 5 inches up from the bottom of the tank,,I assume that is the bottom that we are hitting... Is this the norm?
and we cant put the trailer on a slight lean as recommended because none of the doors would stay open.We did try that...Others that I have read about also have this issue with the tank not emptying out.
I dont remember the smell being this severe last year. Could the heat, along with the permanent site be the problem. is there anything else that any of you could recommend that we try.
thanks for all your suggestions...I hope that there is a fix that we are overlooking, this really puts a damper on our camping.

Boyd · 08-15-2010, 08:58 PM

If no one is able to give you a fix, draw a side view picture of black tank, where pipe attaches, height of pipe and location of fan. Include measurements and I, if not someone else, will be able to figure it out and give you a fix. Oh, and don't forget to post the picture. I'm SURE there is a simple solution....well at least A solution.

LadyWindrider · 08-15-2010, 09:44 PM

I'm curious about your statement that you "measured the vent pipe and it is 5 inches up from the bottom of the tank." How deep is the tank. Let's assume 8 inches, and that would mean once there is 5 inches of liquid in the tank, the vent pipe would be covered and become useless.

One test I would try is: With the tank empty, I would poor water down the vent and see if it goes in the tank. Just to make sure it isn't stopped up. Especially since you attempted to measure the pipe somehow, and hit an obstruction. Good Luck, and let us know where the water goes.

Iggy · 08-15-2010, 10:21 PM

You have your trailer setup on a permanent site.......
If the smell is that bad I do not think you are using chemicals or flushing the tank out correctly and a lot of $%&! is still rotting in the tank.

Are other trailers around hooked up permanently?
Do you keep any of your valves open all the time?
Could you be smelling your neighbors dumping smell?
How often do you full flush your black water tank?
Do you fill it up with fresh water and chemicals or just water?
How many times have you fully filled the black water tank with a hose and then dump?
Just a few questions that may help me figure this out.

NWJeeper · 08-15-2010, 11:12 PM

Are your sure it coming from the toilet? Our bathroom sink is plumbed to the black tank. On our maiden voyage we were overcome by the stench while driving through Arizona. The movement, heat and lack of use of the bathroom sink caused the water in the P-trap to evaporate and therefore no more airlock between the rig and the tank. WheeeWWW!! We learned quickly to give the bathroom sink a shot of water every now and then, especially in storage in hot temperatures to keep the P-trap full.

blue eyes · 08-16-2010, 06:49 AM

now to answer your questions... If we are assuming correctly about the tank,,,..the way we measured the pipe was when we removed the electric fan from the top of the roof vent, we had a direct line to the black tank. We took a tape measure,dropped it down the vent line, hit what I had said we assumed was the bottom of the tank, then we were able to hook the bottom of the pipe itself and it was approx 5 inches from the hard bottom we hit.
Our underbelly is completely enclosed so I dont have any pics to take, that is why I was hoping that someone was able to tell us how deep these tanks were. Do any of you know what they measure? We are fairly new to camping and not familar with alot of how these trailers are setup.
We are using the blue deodorizer and doubling what it calls for to use. We were also wondering about the pipe being too far into the tank and being useless once the tank is about half full. Hoping that isnt the problem,,,and if it is,,,how do we fix it.
We are in a park, so yes there are other trailers, valves arent kept open, use lots of chemicals, fill the tanks clear full with water and have them pumped every other weekend.
We have also filled them on our own and dumped, however, as I posted before, it is such an ordeal doing it this way because we have to make so many trips to the dump station, and after doing this and still not getting any satisfactory results, we stopped. Weekends were spent dumping...LOL
The smell is ,without doubt, coming from our toilet... , we were hoping to be able to find a fix without removing the underbelly. With it all being enclosed, it makes for a more difficult solution.
We still are a bit confused as to why we could smell it when we flush, however, when the vent cap is removed from the line, we dont get any odor. We are having it pumped again,,,this week, and when we go back we will see if we have any odor coming from that pipe on the roof..if we do,,then maybe that pipe is too far down in the tank..
We are still puzzled as to why this tank will not completely empty out,,and it doesnt matter if we dump or they pump...
Thank you for all your suggestion

tentcamper1 · 08-16-2010, 09:48 AM

"if" its the vent pipe, could it have slipped down causing two problems, first when the water in the tank gets above it it becomes useless and second is it leaking sewer gas from where it was connected to the tank. it sounds to me like you are going to have to take the under belly apart and look there. instead of taking the water to the sewer with the tote could you pay the honey wagon to stay there for an hour or so while you flush the tanks as mentioned on other posts. this would be a good time to also find out if the lav is draining into the black tank.

blue eyes · 08-16-2010, 06:49 PM

The pipe slipping would be a very possible reality. Dont know how those things are held together, but from what we have read in previous post, just about anything is possible with the construction of these things.As far as having the pumper stay for an hour or so, is hard to do, he comes on Mondays, when nobody is there..If all else fails, maybe I could take the day and try what you suggested. I am willing to try anything.Never really gave it much thought as to the lav draining into the black tank. Would have thought that if that was what is happening, we would be filling up much quicker than we do..however, as I said, I guess anything is possible... thanks for the reply, I appreciate all the input

LadyWindrider · 08-16-2010, 11:50 PM

I would be pouring water down the vent. If the vent doesn't work, (no smell), you aren't going to dump either. When dumping, you would pull a vacuum and the dump would stop once the tank sucked so far down. the when you flushed the next time, the vacuum would be released in to the room. As for the vent pipe slipping down, I'm not sure. Mine has a flange on top of the tank the pipe sits in, and can't go any farther. I assumed all were that way. Also if it slipped, it wouldn't stick up above the roof, because the factory would never leave it 5 inches too long, waste of good pipe. Could also tell by caulking around it.

**Herk7769** · 08-17-2010, 05:49 AM

Quote:

Originally Posted by windrider

the when you flushed the next time, the vacuum would be released in to the room.

What?

You mean air would be sucked from the bathroom down into the tank to relieve the vacuum, right?

LadyWindrider · 08-17-2010, 07:43 AM

Technically you are correct, but without a lot of computing, that air will overcharge or pressurize the tank momentarily, and the swirl effects will come in to play, and some of the tank air, since it is not a complete vacuum, will be be released back in to the room. Now I hope that is confusing enough.

Also if the vent didn't work, and the toilet was used early in the morning, with cool temps, then during the day the the heat would cause expansion which would pressurize the tank forcing release of vapor in to the room on the next flush.

**Herk7769** · 08-17-2010, 07:52 AM

Quote:

Originally Posted by windrider

Now I hope that is confusing enough.

The mathematical equation for Boyle's law is:

where:
p denotes the pressure of the system.V denotes the volume of the gas.k is a constant value representative of the pressure and volume of the system.
So long as temperature remains constant the same amount of energy given to the system persists throughout its operation and therefore, theoretically, the value of k will remain constant. However, due to the derivation of pressure as perpendicular applied force and the probabilistic likelihood of collisions with other particles through collision theory, the application of force to a surface may not be infinitely constant for such values of k, but will have a limit when differentiating such values over a given time.
Forcing the volume V of the fixed quantity of gas to increase, keeping the gas at the initially measured temperature, the pressure p must decrease proportionally. Conversely, reducing the volume of the gas increases the pressure.
Boyle's law is used to predict the result of introducing a change, in volume and pressure only, to the initial state of a fixed quantity of gas. The before and after volumes and pressures of the fixed amount of gas, where the before and after temperatures are the same (heating or cooling will be required to meet this condition), are related by the equation:

Boyle's law, Charles's law, and Gay-Lussac's law form the combined gas law. The three gas laws in combination with Avogadro's law can be generalized by the ideal gas law.

aintgotnun · 08-17-2010, 08:25 AM

Uhhhh........ Lou, Ya got WAAAAAY too much time on your hands....

**Herk7769** · 08-17-2010, 08:34 AM

Quote:

Originally Posted by aintgotnun

Uhhhh........ Lou, Ya got WAAAAAY too much time on your hands....

I am truly sorry.
With a Chemistry major and minors in Math and Physics I could not restrain myself. (and I should have)

Mea Culpa; Mea Culpa; Mea Maxima Culpa.

Did I mention the minor in Theology?

windstone101 · 08-17-2010, 10:20 AM

I have smelled the toilet odor in other trailers I have owned in the hot summer months here in texas (100+ degrees) with a permanant setup. If the toilet is over the tank go and buy a tank clean out pipe from Camping World or make your own using a 3/4 inch PVC pipe about 3-4 feet in length and put a treaded PVC female coupling where the water hose quick disconnect will be located on one end. Put a cap on the opposite end of the quick disconnect and drill holes about 5/32 in size (small holes) about 8 of them on the side of the cap (all around the cap) where the water shoots out 90 degrees from the PVC pipe. You want to have a forced stream coming out about 3-4 feet wide to reach the sides of the tank to wash all the crap that has stuck to the side walls. May take many cleanings with the PVC pipe to get all the harden crap off the side walls, but will work in time. With the valve open in the toilet bowl all the way open you can move the PVC pipe around and have someone on the outside next to the drain hose listening for the crap coming out of the tank. Sometimes you can get a thump with big clodes coming out of the tank and possible the clodes can stop up at the sewer line drain valve and will need a metal clothes hanger long ways to break and pull out the stoppage. I think around 5 or 7 dollars you can make your own clean out wand. If your not smelling the ordor from the roof then the ordor is in the tank itself and you would not smell the ordor from the roof. Also when you leave from your trailer to go home take a few minutes and use the wand to clean the inside of the tank. Camping World use to sell odor tablets for black tank smells (can look at local dealer who sells accessories) and would dissolve over time in water left in the bottom of the tank. You don't need to fill the tank full everytime just put enough water in the bottom of the tank with your blue chemical power to help with the ordor. I have 40 years of experience with RV's and RV tanks, so I know exactly what is happening with your RV.
A note here: you can take the wand and put the wand from the outside of the trailer thru the dump valve and clean the tank top that away too. Just get a bucket to catch all the crap and water, so you don't pollute the ground around the RV.

LadyWindrider · 08-17-2010, 10:33 AM

Guess I asked for it. regardless of what math you use, apparently the still bottom line is PEW!.

blue eyes · 08-17-2010, 12:02 PM

Windstone I think that I have that gadget that you are speaking of, it threads onto your hose and shoots water out in a spiral direction..I will tackle this project once again.
So what you are saying to do is just keep using this wand to continually spiral water in the tank cleaning the sides of debris that you fill are stuck on the sides leading to the nasty smell, I have gone through the outside valve and feed it up through as you suggested. However, I feel the need is more on the top section of the tank,
Are you familiar with how these tanks are setup? Once you drop down in the tank, does it distribute the water on one side or does it flow in both directions. From what we were told, these tanks are rather long and narrow?It feels as though there is only about a 4-5inch depth from the top of the opening of the tank to the bottom of the tank..
Just still cant understand why we never completely empty..No matter what we have done, from day one, when you look into the tank from the toilet, you can always see water...We never had this in the other trailer, when we pumped out, there was nothing left that was visible from looking down into it, and I guess that I feel that you can never get all the way into the cleaning of the tank if you have water in there to begin with..I hope that I am making sense.
thanks for your reply

cfsoistman · 08-17-2010, 12:04 PM

Wow there's some real technical $#!^ posted here, but no where do I see what model unit has the problem and have you contacted the manufacturer? You could ask how that vent pipe is connected? If it's any type of rubber boot connection it may be too far down in the tank since day one. Ask the manufacturer how deep the tank is. They should be able to provide that information. Maybe that tank is only 5" deep but very flat, who knows? The manufacturer knows!!!At least that could eliminate some possibilities.

**Herk7769** · 08-17-2010, 12:53 PM

Quote:

Originally Posted by windrider

Guess I asked for it. regardless of what math you use, apparently the still bottom line is PEW!.

Totally!

**Herk7769** · 08-17-2010, 01:18 PM

Our tanks look like the attached photo.

The smaller inlet on the top of the tank is the vent.
The larger one on the top of the tank is the inlet from the toilet.

The sensors are on the larger face next to the dump valve outlet.

The tank with the white hose (turbo flush) is the black tank. The one on the left is the gray water tank.

Hope that helps.

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