Gray tank odor problem

[jello_jeep]

I have been chasing around an odor problem in the bus, ok wise-crack artists, place your comments here ---> <--- . Part of it was a diesel odor that was cured by tightening up some clamps on a vent line.

The other part is a gray tank odor. It is worse when the bus has been sitting all closed up ( no surprise here) . You can smell it strongly in the plumbing bay and not as strongly but very annoyingly inside the coach. The only place I could really identify it as coming from, was sometimes it seems like it is getting blown out of the grillwork under the reefer, when the reefer fan is running.

I wasn't looking forward to pulling the reefer for sure as that looks like a big job.

I heard tell of a feller in Lake Havasu City that specializes in cleaning out holding tanks, so I gave him a call. He basically inserts I high pressure nozzle up in the tank, via a clear connector in the sewer line that has a hole in it for the hose. He flops the nozzle around in the tank, and watches the various material wash out down the line. It took about an hour and a half. He charged $150.00. He also dumped some bleach mixture down the P traps to clean them, and lubed the seals in the dump valves.

The guy seemed vary knowledgable and also advised not using toilet chemical once your tank was all cleaned out, but instead using a pint of Lysol, which ever scent you liked.

I mentioned our rally in Pahrump, and he asked if he could do a seminar on holding tanks. Sounds good to me, Skiffer let me know what if anything he has to do to arrange it.

I don't yet know if it cured my problem, as I had to leave the next day.



Anyway I am still baffled at how the odor is coming out from under the fridge. As I was servicing the toe kick heaters (see other thread) I pulled access hatch from the bottom of the bathroom sink base cabinet. I saw a black ABS vent of some sort that says "Best Vent" on top of it. As I was poking around in there, I heard a fan come on, and noticed that there is a raceway that connects that cabinet to the one under the reefer & kitchen sink cabinet.


I have no idea what kind of vent it is, or why its inside? Any of you plumbing experts please chime in! This would sure explain how this odor gets distributed inside! I didn't smell anything coming from it at that point and not sure on how it works, or what causes it to vent. From its placement it obviously comes from the plumbing bay, not sure which tank.

Someone smarter than I (insert more wise cracks here) suggested maybe changing the vacuum breakers. Are these the brass device with the chrome top?


At any rate, please share your thoughts on this!!

[Jon Wehrenberg]

J-J......here are some thoughts.

If your coach is unused for a while the traps in the sinks, shower, etc are dry and the odors from either tank will end up coming through the traps into the coach.

If you are keeping the traps filled then look for traps you do not keep filled such as a dishwasher, washing machine or even the trap for the refrigerator ice or door drain.

Also, verify you are not smelling diesel. Both can be mistaken for one another.

Crude comments to follow.

[Just Plain Jeff]

Odors come from trapped, rotting organic material or water which has 'gone bad.'

The Commander has always recommended the use (again) of Kelley Clamps which Will Be Used to clean any trap: http://forum.prevostownersgroup.com/...ead.php?t=1549 prior to its use by any person.

Furthermore, Bleach Will Be Used to clean any said waste piping immediately upon the cleaning of said traps. (Dilute 1:10) You do get to choose which kind you buy, but only Clorox has been used in our coaches.

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Now my side of the story: In most 'RV manuals' they suggest that fresh water tanks be flushed not less than every 14 days, dry to dry. Gray water tanks the same. Black water the same. If you look carefully at a mixed gray and black water tank (which was outlawed by the RVIA Police in 1992 but are still manufactured) most of them have an inlet, marked or in sleuth mode which can be used to put fresh water into the tank. Since these have a nozzle on the inside, take care to use a different hose than you would for fresh water so as not to contaminate the hose with icky stuff.

If, after all of this and the prior posting you have a gray water smell, chances are that you have either a leak or a loose fitting somewhere around the gray water tank.

As we often suggest here, stand back and look at your water system. Where does the water come from and where does it go? Ice makers, washing machines, dishwashers, instant hot water units are often overlooked by owners if they aren't used much.

Then identify each and every waste system out of the coach and check there. It is harder to check the waste system as it has little or no pressure, but as you have noted, is detectable by odor.

A happy water system is clean from the shore input through and including the tanks.

If you have a macerator, make sure that is used on a regular basis. If it 'locks up,' the best way to fix that is to back prime it from the outlet using the icky hose, get it to run, then unhook the backprime and let it run for a bit.

Although bleach is lubricious, it can be tough on seals and fittings and should be reserved for the waste system on an as-needed basis.

A bit of baking soda now and again on the fresh water intake side can't hurt you and will change the ph and also keep the fresh water tank a tad cleaner, depending upon where you got the water originally and its quality.

The Best Vents aren't. Usually they have to be completely replaced. Winnebagos, no kidding, often use them due to bad waste plumbing design and almost always get jammed up and allow gray water odor to flow.

Now there.

Not a single crude comment.

[Jerry Winchester]

Jon,

Can you not pour something like olive oil or some other oily substance in the traps when you are storing the coach to keep the water from evaporating? Seems I read this somewhere, but I have never done it as I am generally in my coach every week or so.

Any comments on the Lysol deal?

[Jon Wehrenberg]

Jerry,

Yes there are products for that purpose. In areas without plumbing, or in which water is scarce there are waterless urinals. No flushing is required. The principle is that the urine enters the drain which has a certain quantity of an oil or liquid that is both lighter than water and is scented. The urine being heavier than the liquid it passes through it, and the liquid prevents the urine odor from escaping from the trap and also prevents or at least minimizes loss through evaporation.

The use of oils such as olive oil are typically discouraged because any vegetable based oils or animal fats are causes of sewer blockages so the liquid has to avoid having that type of property.

Jeff,

If cleaning makes you feel good have at it. There is no downside except for the cross connection used in flushing which is illegal by every plumbing code in the nation. But if your traps are filled with clean water you should never ever get an odor from a holding tank except at your roof vent, and no amount of cleaning will do you a bit of good after the first use of your system It is like only washing your car when it is going to rain, and then heading down a dirt road immediately after the rain starts.

[Jon Wehrenberg]

Here's the stuff jerry was talking about....

http://www.waterless.com/product.php?product=blueseal

[jello_jeep]

I called Leon from Marathon OR and asked him about the black plastic "best vent". He said there is one at every vented device, sinks, d/w, w/d etc.

They are not normally open, but vent if there is pressure present for some reason, and in a coach at the ten year mark or so, that they will become stuck open. All you have to do is to unscrew the top of it, and screw a new one on.

He said they are available at RV joints, Camping World etc!

I will be getting a handful of those for sure, and when I take the boards back up to replace the toe kicks, I will replace those..

[Just Plain Jeff]

Jerry,



Jeff,

If cleaning makes you feel good have at it. There is no downside except for the cross connection used in flushing which is illegal by every plumbing code in the nation. But if your traps are filled with clean water you should never ever get an odor from a holding tank except at your roof vent, and no amount of cleaning will do you a bit of good after the first use of your system It is like only washing your car when it is going to rain, and then heading down a dirt road immediately after the rain starts.

Trying to keep this conversation civil and within the bounds of common decency, there is a likelihood of some organic matter within the traps which can be rather bothersome to those who have sensitivity to such matters and must be freshened up from time to time.

As to the common single waste tank, the RVIA outlawed same in 1992, however many converters have continued the use of them up to the current day. Don't shoot the messenger.

Even at some hoity-toity rallies, the direct discharge of gray water is not only allowed by suggested by the hosts and hostesses thereof.

-You can see that this topic can be discussed with discretion and articulated with common manners.

-There are even some coaches where there is a likelihood of black water entering into the fresh water supply, however I have chosen not to specifically address that issue here for the benefit of the kinder, gentler approach we are taking these days here.

Have a wonderful afternoon.

[Jon Wehrenberg]

I also have refrained from making less refined posts regarding this matter.

J-J...They are known in the industry as air emittence valves. They are usually frowned upon, and in most plumbing codes they are forbidden. Typically they are used as a substitute for a roof vent. There are applications where they are allowed such as in a home with an island sink, where there is no wall or vertical structure in which a vent pipe to the roof can be run.

JPJ,

I was specific in calling out fresh water in the traps. J-J's post about the vents clear up the matter and it is more about his plumbing system design that any material which may be in the drain or vent system. My only comment about cross connections is that they should be avoided at all costs, but in the event a coach has any there should be fail safe ways of providing backflow protection.

[win42]

Sometime back we got on this odor/clean the tank subject. Jon mentioned to a couple of us the merits of dumping about a half gallon of Cascade consentrated liquid dishwashing soap down the stool and the grey water devices. Left there with about a half tank of water to slosh around as you head down the road. will clean the tank interior and cleans the sensors on the tank walls that send signals to your tank level indicators. In our case this method cleaned the grey and black tanks and eliminated tramp odors floateing from the tanks. Repeat this method every few months. The soap was not that expensive and does the job.

Old Guys Know Stuff.