| Author | Message | ||
| S Davidson (Sdh3)
Registered Member Username: Sdh3 Post Number: 13 Registered: 7-2006 Posted From: 69.19.14.43 Rating: N/A |
After much reading, hmmming and hawing, we decided to vent our septic through the engine. Keeping more holes out of the roof seemed like a good idea. We have been having septic smells though in the bus, especially when we turn on our 'fantastic' vent, to remove smells and humidity from the bus, or when running the washing machine. Yes, the water traps throughout the bus are always full. Before we go cutting holes in the roof, is there something we may be missing? | ||
| George M. Todd (George_mc6)
Registered Member Username: George_mc6 Post Number: 681 Registered: 8-2006 Posted From: 207.231.75.253 Rating: N/A |
As in you're NOT vented thru the roof now? Do you mean engine as in air cleaner, or as in engine compartment? (Doesn't matter, DON'T DO EITHER!) It smells to me like you're not properly vented thru the roof now. When the washer empties into the grey tank, the air above the water in the tank has to go somewhere, which is why there is at least a 1 1/2" vent out the roof from the top of each tank, straight up, NO trap. One other thought: Where does the air come from to replace the air exhausted by the fantastic vent? As in open a window, instead of making it come in thru little holes everywhere. G | ||
| Glenn Williams (Glenn)
Registered Member Username: Glenn Post Number: 178 Registered: 6-2006 Posted From: 216.163.57.189 Rating: N/A |
When I plumbed my bus, I did not want the extra holes either. So I ran my black water tank vent behind the fridge, and then through the fridge vent cap. Works flawlessly. For the grey water tank, I put a 90 degree bend off the top of the tank and ran it out the rear wheel well. Again, no smell at all. I think I got that idea from Ace. Good luck! Glenn | ||
| John MC9 (John_mc9)
Registered Member Username: John_mc9 Post Number: 736 Registered: 7-2006 Posted From: 72.146.79.49  Rating: N/A |
Hey "S" - Glenn's fridge vent idea is good, as is Ace's! But you oughta' keep in mind, that you can go out the side (near the roof line), rather than the roof itself. The gas will still rise at it should, and you won't have to worry about parking on a hill... Many of the new commercial motorhomes have vents out the side, especially when the kitchen is built on a slide-out! And that includes fridge vents as well as water/sewer! Cheers! | ||
| Len Silva (Lsilva)
Registered Member Username: Lsilva Post Number: 192 Registered: 12-2000 Posted From: 71.99.25.84  Rating: N/A |
The powered tank vents work quite well to maintain a slight vacuum in the tank. These are not too expensive but it doesn't look difficult to roll your own, maybe even solar powered. http://www.lslproducts.com/index.html | ||
| Bruce Henderson (Oonrahnjay)
Registered Member Username: Oonrahnjay Post Number: 340 Registered: 8-2004 Posted From: 72.12.39.78  Rating: N/A |
How far should a "side vent" be from an openable window? | ||
| Tim Brandt (Timb)
Registered Member Username: Timb Post Number: 247 Registered: 10-2003 Posted From: 66.165.176.60  Rating: N/A |
Not a bad idea Len. Probably not as strong as the one listed but solar vents are pretty common in the marine world for cabin ventilation  | ||
| Larry & Lynne Dixon (Larry_d)
Registered Member Username: Larry_d Post Number: 182 Registered: 7-2005 Posted From: 71.111.188.44  Rating: N/A |
We are vented out the top and had a cap on the pipe and got bad smell when traveling down the road. A power vent was suggested, also taking the cap off and putting a T on the top rather than a cap. I put a T on perpendictular to the coach and it eliminated all smell, we get none. A T was put on both pipes. Just adding to other ideas. 4905 Larry | ||
| Dan West (Utahclaimjumper)
Registered Member Username: Utahclaimjumper Post Number: 151 Registered: 1-2005 Posted From: 208.66.38.60 Rating: N/A |
I did one better than that, a "T" in such a way to create a venturi effect when moving, works great!!>>>Dan | ||
| James Robinson (Jjrbus)
Registered Member Username: Jjrbus Post Number: 183 Registered: 12-2000 Posted From: 70.10.86.155 Rating: N/A |
I tried the power tank vent "LilStinker" My experience was it did not hold up well. They are simply a box with a small computer fan. The computer fans did not like a humid enviroment. I replaced the fan twice and then threw out the powered vent. If doing it again I would use a bilge blower, which are designed for humid enviroments. | ||
| John MC9 (John_mc9)
Registered Member Username: John_mc9 Post Number: 737 Registered: 7-2006 Posted From: 72.146.76.156 Rating: N/A |
Bruce - I don't know what the specs are, but I would imagine if that question was asked about the proximity of roof vents, the answer would be as similar. Our Winnebago's intake/exhaust vent was directly in front of the black/grey tank vent. The "Georgie Boys" vents for the fridge, roof intake/exhaust, and the plumbing vents were all on the same side, and within 2' of each other. | ||
| Gus Causbie (Gusc)
Registered Member Username: Gusc Post Number: 799 Registered: 11-2005 Posted From: 208.54.200.37 Rating: N/A |
My black tank vent pipe goes slightly above the top of the tank (To prevent overflows, then back down through the bottom of the bus, works great. No odors, no holes in the roof or pipes through bus, the whole thing is in the tank bay. I got this idea from Ace on the other bus forum about a year ago. (Message edited by gusc on January 08, 2009) | ||
| Bruce Henderson (Oonrahnjay)
Registered Member Username: Oonrahnjay Post Number: 341 Registered: 8-2004 Posted From: 72.12.39.78 Rating: N/A |
In my part of the world, anything larger than the point of a pin is going to have an insect going into it (ever make a landing with an ASI reading "0"?, DAMHIK). Does anyone put screeens etc. over black/grey-tank vents? | ||
| Ednj (Ednj)
Registered Member Username: Ednj Post Number: 225 Registered: 3-2003 Posted From: 68.197.95.38  Rating: N/A |
Here's what I did, always on the Low pressure side. Natural draft. But it's through the roof. 1 on the gray tank and 1 on the black tank.  | ||
| Douglas Wotring (Tekebird)
Registered Member Username: Tekebird Post Number: 389 Registered: 10-2004 Posted From: 71.59.75.212 Rating: N/A |
my 04 for better than 30 years was vented out the bottomwith a simple U turn out the top of the tank then straight down. never had any internal smells key is proper placement and diameter and good wet Toilet seals | ||
| Gus Causbie (Gusc)
Registered Member Username: Gusc Post Number: 800 Registered: 11-2005 Posted From: 208.54.200.62 Rating: N/A |
Like Doug says, no need to make this thing so complicated. | ||
| Douglas Wotring (Tekebird)
Registered Member Username: Tekebird Post Number: 390 Registered: 10-2004 Posted From: 71.59.75.212 Rating: N/A |
my Custom Coach built MC-8 is also Vented through the bottom. | ||
| John MC9 (John_mc9)
Registered Member Username: John_mc9 Post Number: 738 Registered: 7-2006 Posted From: 72.146.76.199 Rating: N/A |
"S" - One other thought crossed my noggin... If you're using a standard RV type toilet, make sure you fill the toilet overflow, after you drain the system. We would fill the toilet to the top, and let the water run out the toilet's overflow. That insured the built-in "P-trap" of the toilet had water in it, to stop the raw odors of the holding tank to stench up the living quarters! It's amazing, how few avid RVers knew to do this. The entire rig can stink like hell, if it's overlooked! Cheers! | ||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 627 Registered: 10-2006 Posted From: 66.82.9.75 Rating: N/A |
Big problem is not All RV toilets have a P trap. You can experiment with a piece of masking tape over the bowl overflow , and open a forward window at cruise speed. You will know in about 10 seconds afrer opening the window. FF | ||
| Tony Gojenola (Akbusnut)
Registered Member Username: Akbusnut Post Number: 30 Registered: 11-2006 Posted From: 208.98.151.220 Rating: N/A |
Mine is vented through the roof. I have a sealand toilet and have had occasional odor problems - usually when underway in windy conditions. Last year I had to replace the seals in the toilet. When I took it apart I found that the overflow was a direct line bypassing the water seal - no trap. So, when I reassembled the two body parts I simply reversed the gasket which then blocked the overflow. I have had no problems since, but of course some might fret a possible overflow sometime. | ||
| john w. roan (Chessie4905)
Registered Member Username: Chessie4905 Post Number: 1281 Registered: 10-2003 Posted From: 71.58.110.9 Rating: N/A |
That overflow tube causes most of these problems in all those toilets. If concerned about running over when unattended, have a shutoff valve there or a solenoid in water supply system to shut off water when away from coach. Unless you don't have a water pressure tank in system. For that, a normal pump switch will do. | ||
| john degemis (Degemis)
Registered Member Username: Degemis Post Number: 34 Registered: 3-2008 Posted From: 71.92.155.232  Rating: N/A |
Great timing for this topic. Just getting ready to start putting in tanks. Like the idea of venting out bottom. For the purpose of letting air into the tank so things flow and for overflow both make sense to me. But doesn’t black water produce gas? And if so will it force its way out thru the bottom? | ||
| Arnie Smith (Arniemc5a)
Registered Member Username: Arniemc5a Post Number: 10 Registered: 11-2008 Posted From: 24.71.46.230  Rating: N/A |
For what it's worth.. A thought occurred to me that if you vent out the bottom of the coach, it is fine when you are on the move, but when you stop at your favorite parking/camping spot, where is the odor going to go. A light breeze blowing under the coach will cause a venturie effect and the odor will carry on down wind. If you are down wind that could be rather annoying, and if it is blowing it the direction of your neighbor's lot.... I won't go there... Just food for thought Arnie | ||
| Gus Causbie (Gusc)
Registered Member Username: Gusc Post Number: 801 Registered: 11-2005 Posted From: 208.54.200.1 Rating: N/A |
John, Yes, gas will move out the vent by its own pressure plus the pressure from waste coming into the tank. That is the whole idea, don't want the odor in the bus. Remember to run the vent line higher than the waste tank before it goes out the bottom of the bus. This is also your overflow pipe in case you let it overfill. Never had an odor problem with my bottom vent, moving or parked. I always presumed the gas went up as soon as it cleared the bottom of the bus, thus no neighbor problem. We're not talking big time gas generation here. I have a water pump switch on my toilet wall. We always shut off the water when not using it even when in the bus. With a switch at the toilet there is no chance of ever being on the john without water!! | ||
| FAST FRED (Fast_fred)
Registered Member Username: Fast_fred Post Number: 633 Registered: 10-2006 Posted From: 69.19.14.29 Rating: N/A |
"Like the idea of venting out bottom." Sometimes "saving" effort can be costly. Why not work out extra use for the roof vent? WE use it as a down feed for the solar panel , really EZ to get water tight . One working hole in the roof , instead of 2. FF | ||
| Ednj (Ednj)
Registered Member Username: Ednj Post Number: 227 Registered: 3-2003 Posted From: 68.197.93.24 Rating: N/A |
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| Don Evans (Doninwa)
Registered Member Username: Doninwa Post Number: 175 Registered: 1-2007 Posted From: 208.81.157.90 Rating: N/A |
Something to consider no matter where you vent things. Is it a low pressure area when you are rumbling down the road, as in sucking out which can empty you drain traps? Is it a high pressure area that can blow fumes back through the traps? It is not always easy to tell. That is the reason for the various vent cap designs for roof top installation. They try to neutralize the effect of air rushing past. If you put the vent somewhere else and it has either constant high or low pressure it could be a problem. The fact that many people report venting under the coach with no ill effects may mean it is just not that critical. If you have no odor when camped, but odor during or immediately after travel you may be sucking or blowing out the traps. Don 4107 | ||
| Gus Causbie (Gusc)
Registered Member Username: Gusc Post Number: 802 Registered: 11-2005 Posted From: 208.54.200.40 Rating: N/A |
Don, I haven't tried to get too scientific on this. It works, so the other stuff is immaterial. |