So I recently received an email to the RV Doctor Website that rang of a familiar recurring theme; holding tank odors permeating the interior of the RV. I receive similar emails every season, year in, year out, without fail. RV holding tank odors have been with us since the dawning of the modern age of RVing. Dumping holding tanks, dealing with marine-type toilets and trying to avoid nasty waste plumbing odors from both the liquid waste (gray) system and the solid body waste (black) system, have plagued RVers for far too long.
Enter a relatively new device (ten years in the perfecting), called the 360 Siphon, as produced by 360 Products, Inc. The 360 Siphon is scientifically designed to take advantage of the normal occurrences of air flow over the recreation vehicle, effectively extracting fumes and sewer gases and the subsequent odors, rather than finding a way to "hide" or masquerade those displeasing odors that naturally occur.
The Laws of Physics are irrefutable so it makes sense to use those natural phenomena to solve the problem, rather than be forced to mask RV holding tank odors, usually with another distracting, obnoxious odorant. But before I get too far ahead of myself, perhaps you or someone you know has had the experience that Barb recently went through:
Dear RV Doc, we recently inherited my in-laws' 20-foot 5th wheel. Everything's great except for the holding tank. When we travel it releases a horrible smell. We keep the bathroom ceiling vent closed and the toilet lid closed with some water in the bowl, but the smell continues to escape. Once we have parked and the tank becomes more full, the smell lessens somewhat. I know that my in-laws did a lot of rough camping where they didn't use a dump station. We're wondering how do we get rid of it? Barb, (Victoria, BC)
Here's my response to Barb:
Barb, I wish I had a nickel for every email I receive that concerns RV sewer odors inside the RV, whether moving or stationary! All holding tanks on RVs are susceptible to the proliferation of odors, even though it’s the solid waste (black) holding tank that gets most of the attention. The combination of human waste, moisture and in most cases, the use of a holding tank additive, results in a captive, living, biological playground environment of sorts, (which we just happen to carry around with us), that is continually active and thriving. The best additives, by the way, actually contain live bacteria that react with the moisture to help breakdown the solid components to make dumping and flushing easier; so that's a good thing!
The secondary aspect of biodegradable additives like Pure Power Blue (my recommended treatment), is odor control. By attacking and digesting the actual odor-causing molecules at their source, odors are controlled and in some instances, eliminated altogether. The not-so-good additives simply mask the odors with an odor all its own. This entire process, unfortunately, will always create objectionable odors; it’s a natural happenstance with RV waste containment. It's also one of my RV Facts of Life. The key is to get rid of these odors as quickly as possible.
Venting is the primary method of allowing odors to exit the confines of any holding tank. All holding tanks are vented through the roof of the RV. In most cases, each tank will have a separate vent stack that runs from the top of the tank, up and through the roof. Driving down the road (movement) and peculiar air flow movements over the top of a parked RV (stationary) can and will create a positive atmospheric pressure inside the holding tanks. It’s this positive pressure inside the tanks that force fumes, odors and other airborne contaminants into the living sections of the RV.
Venting is the primary method of allowing odors to exit the confines of any holding tank. All holding tanks are vented through the roof of the RV. In most cases, each tank will have a separate vent stack that runs from the top of the tank, up and through the roof. Driving down the road (movement) and peculiar air flow movements over the top of a parked RV (stationary) can and will create a positive atmospheric pressure inside the holding tanks. It’s this positive pressure inside the tanks that force fumes, odors and other airborne contaminants into the living sections of the RV.
Unfortunately, it’s all too common. Flawed vent designs, improper water locks inside P-traps, fouled toilet gaskets, faulty anti-siphon trap vent devices, sloppy workmanship and improper roof sealants, all contribute to an easy entry for holding tank odors to permeate the living portions of an RV. The integral vent stack is literally taken out of the equation since the odors have found an easier path rather than traveling all the way up the stack and through the roof, especially if it has to fight against the downward movement of air coming into the tank. And as I state in my seminars, you, unfortunately, then get to inhale the results.
Surprisingly, there is no requirement for coach builders to install a vent cap on the roof and those that do, often install an inexpensive cap that can actually exacerbate the problem. Typical vent caps are designed primarily to keep leaves, dust, dirt and critters from entering the holding tank vent pipe. They do little, if anything, to help rid the odors from the waste system. None are designed to specifically aid in creating a negative atmospheric tank pressure. None, except a new type of non-moving vent assembly called the 360 Siphon.
Surprisingly, there is no requirement for coach builders to install a vent cap on the roof and those that do, often install an inexpensive cap that can actually exacerbate the problem. Typical vent caps are designed primarily to keep leaves, dust, dirt and critters from entering the holding tank vent pipe. They do little, if anything, to help rid the odors from the waste system. None are designed to specifically aid in creating a negative atmospheric tank pressure. None, except a new type of non-moving vent assembly called the 360 Siphon. 
This unique roof vent automatically decreases the atmospheric pressure inside the holding tank and literally draws vapors and subsequent odors out of the tank through the vent pipe. The faster the air passing over the vent opening, the quicker odors are drawn out of the holding tank. The big plus is that it contains no moving parts and is easy to install. Any RV handyperson can install the vent (or replace existing vents), in a matter of minutes. If it sounds like I’m a big fan of this device, it’s because I am! It truly works! It’s one of those products that come along every few years that truly solves an obnoxious problem common to virtually every RV.
In a perfect world, all RVs would be outfitted with the proper equipment to be able to manage and alleviate all the displeasing aspects of RV waste management. The products and processes certainly exist, but unfortunately not every coach manufacturer takes advantage of them. Thankfully, as RV owners, we have alternatives that allows us to realize the best of all practices.
I have spent an enormous amount of time over the past few months looking seriously at the issue of RV waste management and have written extensively about processes and products I have tested that have proven quite effective at minimizing RV owner dissatisfaction. To read my complete RV Waste Management article, click this link.
The beauty of the 360 Siphon vent is that every little aspect of the design is scientifically influenced. Every bump, indentation and feature of the sturdy poly-carbonite vent has been engineered for a specific purpose; to take advantage of airflow dynamics and to create a negative pressure inside each holding tank. This is not just a simple, inexpensive ABS plastic molded device to keep leaves and critters out of the vent pipe!
Though other rotating, air-catching, mechanical sewer vent devices have proven effective in the past, (I've personally tested two such products), the design of the 360 Siphon exceeds the successes of those with moving components. With no mechanical parts whatsoever, the 360 Siphon is guaranteed to extract sewer odors and literally draw fumes up and out of the tank. This updraft, governed by the Laws of Physics, totally eliminates the possibility of odors coming into the living areas of the RV.
I think an earlier paragraph bears repeating here: "In a perfect world, all RVs would be outfitted with the proper equipment to be able to manage and alleviate all the displeasing aspects of RV waste management. The products and processes certainly exist, but unfortunately not every coach manufacturer takes advantage of them. Thankfully, as RV owners, we have alternatives that allows us to realize the best of all practices."
To order your own 360 Siphon vent assemblies, contact Drainmaster.com.
Click the video box to see a short video that shows how the 360 Siphon actually works!
Click the video box to see a short video that shows how the 360 Siphon actually works!
Remember, RVing is more than a hobby, it's a lifestyle!
