It's about that time to pick the waste tank for the 102D3 (the 40ft). I have chosen the rear most bay for the fresh water (passenger side) and waste tank (driver side). I have seen someone use a plastic barrel, but I'd like to keep it rectangular if possible for a better fit, and more volume. Black and gray will be combined. We don't boondock more than a few days at a time anyway. Any suggestions or preferred suppliers?
For the toilet I am planning on using Thetford Marine Tecma macerator, to aid with the passage of fluids from toilet in the OEM lavatory location to the rear bay.
The black/gray tank vent will probably follow the same route, and out through the bustle.
Bustle -
You're not removing the factory restroom? :o
Do you realize that underneath the stainless steel floor you've got 20+ years of urine-soaked plywood, the smell of which you'll never get out of the bus by leaving in the OEM lav? Especially in the summertime!
Anyway, to answer your question, I would suggest you order your tanks from Ardemco - one of the advertisers in Bus Conversions Magazine. By doing so, you're helping to support a vendor that's been supporting the magazine and this forum for over 25 years now. If you can't find a pre-made size in their catalog, they'll custom make one to your specifications, plus they'll spin in any fittings you may need, too. They may not be the cheapest, but their quality is excellent - you get what you pay for.
Code is having the fresh water, shore power, and sewage drain all on the driver's side, and all relatively close together.
Where are you placing the house batteries? My coach has them (four marine deep-cycle 8Ds) on the passenger side, rear bay, with the 150g fresh, 90g grey and 60g black tanks on the driver's side. Straight drop from electric Microphor toilet into black tank - no pipe run. Wye fitting allows grey to flush black, if necessary. Tanks vent straight to roof (with a mushroom cap) via the rear corner of bathroom vanity & medicine cabinet. This configuration allows the major "heavy" house systems' weight to be carried by the drive and tag axles.
(Side note: Previous coach had a 100g grey/black tank. Had to use a lot of chemicals to keep the smell under control. Not so much of an issue with the separate grey/black in current coach, as grey drain is usually left open while hooked up. When closed, the grey stinks before the black! Also, don't waste your money on over-priced "rv holding tank chemicals", simply use the septic tank tablets found in any hardware store.)
FWIW & HTH. . . ;)
Quote from: RJ on October 20, 2021, 02:48:15 AM
You're not removing the factory restroom? :o
Do you realize that underneath the stainless steel floor you've got 20+ years of urine-soaked plywood, the smell of which you'll never get out of the bus by leaving in the OEM lav? Especially in the summertime!
You ain't kidding. This was probably the worst thing ever. The smell was unbearable in the 100F heat. How much more of the plywood should I remove? We are putting another layer on top of this one. Should I also replace those insulating blankets that are underneath the plywood?
Quote from: RJ on October 20, 2021, 02:48:15 AM
Anyway, to answer your question, I would suggest you order your tanks from Ardemco - one of the advertisers in Bus Conversions Magazine. By doing so, you're helping to support a vendor that's been supporting the magazine and this forum for over 25 years now.
If you can't find a pre-made size in their catalog, they'll custom make one to your specifications, plus they'll spin in any fittings you may need, too. They may not be the cheapest, but their quality is excellent - you get what you pay for.
Will do - I will give them a shout today. I saw the ad pop-up yesterday after I posted my question.
Quote from: RJ on October 20, 2021, 02:48:15 AM
Code is having the fresh water, shore power, and sewage drain all on the driver's side, and all relatively close together.
The plan is to have all of that on the driver's side, just like a traditional RV.
Quote from: RJ on October 20, 2021, 02:48:15 AM
Where are you placing the house batteries? My coach has them (four marine deep-cycle 8Ds) on the passenger side, rear bay, with the 150g fresh, 90g grey and 60g black tanks on the driver's side. Straight drop from electric Microphor toilet into black tank - no pipe run. Wye fitting allows grey to flush black, if necessary. Tanks vent straight to roof (with a mushroom cap) via the rear corner of bathroom vanity & medicine cabinet. This configuration allows the major "heavy" house systems' weight to be carried by the drive and tag axles.
The current plan is to have electrical (inverter chargers, panels, transformers..) and 20 kWh of LifePo4 closer to the front of the bus; front bay.
Quote from: RJ on October 20, 2021, 02:48:15 AM
(Side note: Previous coach had a 100g grey/black tank. Had to use a lot of chemicals to keep the smell under control. Not so much of an issue with the separate grey/black in current coach, as grey drain is usually left open while hooked up. When closed, the grey stinks before the black! Also, don't waste your money on over-priced "rv holding tank chemicals", simply use the septic tank tablets found in any hardware store.)
FWIW & HTH. . . ;)
I've only used the rv holding tank chemicals that came with our Class-A. Previous owner had a stash that we went through over the span of a few years. Most of those treatments are made out of formaldehyde and some kind of fragrance, so not the best thing anyway. For the past few years I've been using the modified version of the "Geo" method - while it does nothing to control the smell of current content, it helps move things along faster, and prevents sticking. The trick is to not hold on to the content for too long to give it time to start breaking down.
Our black tank always starts off with 5 gallons of fresh, and treated water (oxyclean+calgon+cheap detergent), which allows us to use "quality" plush household Cottonelle toilet paper. Trick here is to not dump immediately after using the bathroom. You need to give it at least 30 minutes to start disintegrating in water. You can test your toilet paper in a cup to see how fast it disintegrates after getting wet.
For the smell moving forward - I think we will get no smell coming out of the tank through the toilet, or the sinks/showers due to venting and p-traps.
Here is the toilet we were looking at using, at the same location where the existing toilet was. The plumbing will probably be routed through the interior behind a service chute that's covered by the interior.
https://www.youtube.com/watch?v=W9pvWgslYjU
Quote from: Bustle on October 20, 2021, 05:04:26 AM
You ain't kidding. This was probably the worst thing ever. The smell was unbearable in the 100F heat. How much more of the plywood should I remove? We are putting another layer on top of this one. Should I also replace those insulating blankets that are underneath the plywood?
Excuse my ignorance, I wasn't aware that you were removing the factory restroom.
Thanks for the pic - the visual helps. I would cut/remove the plywood and insulating blankets as far back as you can see staining, which may be another 8"-12" from where you already are. The wall insulation may also have some staining, another source of smell.
That rusted out metal should also be addressed in some manner before you hide it with new flooring, which I'm sure you've probably already figured out.
Please refresh my memory as to why you're putting your toilet in the same location as the factory, instead of directly over the black tank like 99.99% of conversions do? I'm trying to understand your logic here.
Without having any experience with macerator systems, the Thetford you referenced is interesting - but having p-traps concerns me, especially if the Cottonelle plugs up the impeller before it has a chance to start breaking down.. The KISS system of the straight drop is my preference, as it is for most busnuts.
Something else to consider - the wastewater drain. As you can see in these photos, on my coach the drain is thru the floor of the baggage bay. Biggest advantage to this is that I can leave the bay door closed when not dumping. Biggest disadvantage is that when the coach settles as the air bleeds off, there's quite a sharp bend to the flexible sewer hose, but not so severe that it hampers flow. My MCI had to have the bay door open to attach the sewer hose, too each his own. I like the closed bay system better for me, because I normally leave the grey tank drain valve open when parked with full hookups, thus I can leave the sewer hose attached.
I've added the clear elbow with the flush attachment in order to rinse the black tank after dumping. The white PVC elbow and hose connection gives me a way to leave this all hooked up while parked, and the duckbill gasket keeps the effluent out of the hose, somewhat, but I normally turn on the water slightly so there's flow before pulling the dump valve. I use a brass "wye" with on/off ball valves at the park's water supply - one side fresh water into the coach, the other side to the black tank rinse. I use a pressure regulator on the fresh water side, but none on the rinse side, which hasn't been an issue.
FWIW & HTH. . . ;)
I have always kept the valves closed till emptying. Then letting the black water empty first, opening the grey to back flush into the black compartment, close off the grey, letting the now cleaner black empty. close off black and empty the Grey, clearing the throat, so to speak. I then put some clear thru the toilet and add some chemicals to break down any leftovers, which get swished around on movement, havent ever had the caked cone problems with this technique, lvmci..
I'll be building my tanks and drains to run a 2" valve from the gray to the opposite side of the black from the 3" drain, with a smaller bottom drain for the gray. The 3" will go through the panel behind the rear bay door, possibly with a cable pull on the valve mounted through the panel so it's accessible from outside.
This way I'll drain the black, then drain the gray through the black which should flush it. The small drain is in case the gray gets full and needs drained off some. I'll put a fitting for a green or black hose on it.
Hope to get started on welding up the tanks (plastic) this winter.
Jim
Quote from: Bustle on October 20, 2021, 05:27:12 AMOur black tank always starts off with 5 gallons of fresh, and treated water (oxyclean+calgon+cheap detergent), which allows us to use "quality" plush household Cottonelle toilet paper. Trick here is to not dump immediately after using the bathroom. You need to give it at least 30 minutes
Very interested in your special potty stew. Where did you come up with that combo?
Having just ordered my tanks, my advice is to find a pre-made tank that will work for you. I was sure I was going to do custom tanks to fit the unique dimensions I wanted. I pretty quickly realized that it would cost me 2-3X more than what I could buy "off the shelf" for the same volume tank. I will have to do a little more structure around the tanks because they won't fit as tight, but the cost savings is HUGE. I will have 200 gal of fresh and 170 gal of combined black/grey.
I started with my most critical dimension and went from there to find tanks which would fit within where I wanted them and give me the most volume. I had originally wanted 200/200, but I can live with 200/170 to save a serious chunk of $$$.
Don't get too stuck on "RV tanks" on the websites, especially for the fresh water. I happened to end up going with a potable water loaf tank for fresh water and a RV tank for black.
Also, don't forget shipping... Because of their dimensions, these things get expensive to freight.
about halfway through the travels this summer, we started waiting to dump first thing when we got to a new campground. Assured everything was broken up. Flushed thoroughly also.
Quote from: RJ on October 20, 2021, 11:42:06 PM
That rusted out metal should also be addressed in some manner before you hide it with new flooring, which I'm sure you've probably already figured out.
All of the rust has been cleaned up and neutralized. I don't think I'll be welding any more new metal.
Quote from: RJ on October 20, 2021, 11:42:06 PM
Please refresh my memory as to why you're putting your toilet in the same location as the factory, instead of directly over the black tank like 99.99% of conversions do? I'm trying to understand your logic here.
In our original floor plan the RV type toilet was going to be right above the bay. Since we got a 40ft bus instead of 45ft bus as planned we had to re-do the floor plan. We have to sets of bunks, another single, and a pull out couch. Enough sleeping space for 7.
Quote from: windtrader on October 21, 2021, 10:09:37 AM
Very interested in your special potty stew. Where did you come up with that combo?
It's a concoction sometimes referred to as "Geo" method, or improved Geo. It's popular on the RV boards.. Some people swear by it. It's mostly benign, but Calgon water softener does help prevent sticking from my empirical observation, but so does actually having more water content ;)
With the usual RV toilet, I recommend once you are parked, keep water in the bowl. How much is up to you but don't be stingy. That helps several ways. Kids dropped in the pool will keep their heads down, you get a good flush, and there is adequate fluid for liquifaction in the tank. Sometimes it isn't obvious.
Adequate venting is the next big thing. If you can encourage airflow through the tank it will help immensely.
Jim
Quote from: Jim Blackwood on October 22, 2021, 07:49:05 AMAdequate venting is the next big thing. If you can encourage airflow through the tank it will help immensely.
Jim
Yes, I jotted that down awhile back. Had not considered the biological process releases less bad odor when the tank is aerated with fresh water. One of the many projects on the list is to add a computer pancake fan to ventilate the black box and it can also pull air through the potty hole and prevent any smell from entering the coach. Seems like a double win
make sure the roof vent isn't adjacent to a ceiling fan exhaust.
I talked to a guy that got used 275 gallon IBC totes. You can pick them up almost anywhere on FB marketplace for $50-$150
Surplus city near home sells them for 75 bucks. Was tempted to buy one, but couldn't think of anything I'd use it for. They are really nice. Nice large drain valve on bottom. Might be too high.
U S Plastics Corp. May have something to suit. They have hundreds of different tanks and containers in various sizes. I've purchased from them and very happy with two different style tanks.
Although one big tank makes sense to me I have to agree with others that the grey tank can be the stink culprit. Not sure combining them is a good stink idea despite needing less plumbing, less dump valves etc.
When we full timed for a year we battled the stink until we talked others. We started being careful to wipe off plates and not send anything greasy down the sink. But perhaps shower water has more stink than we think? I also spend more time flushing at campgrounds. Makes me feel like I am getting more value for paying more to spend the night. We send a Home Depot bucket of hot water with Dawn down the grey. Same with the black but add some Calgon. After a bit, I take the time to fill both tanks completely and pull the handles. It takes time but it is their water and sewer. I do that twice. I am convinced the higher water volume sucks a lot of "bad" out of the tanks. At home I leave 5 gallons of water with Dawn in the black and about a gallon of same in the grey. After I started doing that we have no stink and perhaps because of Dawn the valves work much better when I dump. We use Camco when on a trip and it works great on the black tank. LOTS of water has been our best friend and though we boondock a little, always use a campground the night before coming home. Dump tanks twice and use rest areas if we can coming to home plate.
IBC TOtes - hillybilly hot tub!
Add tank flush to each tank you can buy the kits or make your own, they are great to breakup the paper and solids in the black tank and food partials in the gray tank to keep the smell down and they are priceless when you have keys in your shirt pocket and down the toilet they go :-* don't ask how I know that,they are nice to have
I'm thinking a bilge fan for a boat inline in the roof vent will be a handy accessory, wired to come on with the restroom light. But also a second low level vent so that convection heating can keep air moving through the tank under average conditions.
Here's the thing though, the stinky gasses are heavier than air and tend to accumulate in the roof vent line like a stand pipe. Then when you open the toilet flush valve they rush back down the vent pipe and up out of the toilet. So the key is to not let them stack up in the vertical vent.
Using convection to move the gasses up may not be enough and they may escape out the lower vent, but the presence of fresh oxygen will keep them from being created in the first place.
Jim
Quote from: Jim Blackwood on October 23, 2021, 09:16:10 AM
......but the presence of fresh oxygen will keep them from being created in the first place.
Jim
Full stop, nothing else required. 2 decent sized vents, nothing else required.
In line fans obstruct natural air movement, introduce unneccesary complexity.
Keep the toll window closed when flushing at speed... nothing can defend against that suction...
Happy coaching!
Buswarrior
I know you guys had many discussions here on this topic about venting. I personally haven't given much thought to venting yet... but one thing is for sure, your vent needs to be higher than the toilet bowl... 60mm fan can pull 12 CFM of air. It's plenty airflow going through 1.5"-2" pipe. If you are pulling air out, you also don't want any negative pressure in the tank either, so you need an air inlet. Traditional RV tanks only have 1 inlet/outlet. However, different school of thoughts on this. Do you aerate your tank or not? (rhetorical) I think they are called holding tanks, and not septic tanks for a reason. The "inlet/outlet" is not there to vent, but to let gases escape when you put content in the tank, otherwise, you'd get burping back into the coach. While a fan sounds like a great idea, it could be bad idea, as you would be aerating bacteria, and promoting faster decomposition of your tank content. There is a reason why they put formaldehyde in those black tank treatment/odor reducers.
I believe we will get zero smell coming out of the toilet with the macerator toilet I posted, unless there is a defect in the toilet. It's going to be impossible for tank air to escape out of the water trap it has self contained.
Downside? $600 for the plastic throne, and 12v/24v...
You've got it backwards...
Formaldehyde was put into toilet chemicals, toilet chemicals were invented, because the RV industry won't build a proper holding tank, to save a few $$ in manufacturing.
Similar for the marine folks, who have the added challenge of not being able to completely drain their tanks with the pump-out.
Smelly bacteria thrive in low oxygen, the good bacteria, that accomplish things, need fresh air. The smelly bacteria do NOT thrive in fresh air. Make the air in the tank fresh, no bad bacteria will thrive to stink.
This is a topic where going with the masses, gets you the same smelly results.
Dare to put in a pair of inch and a half vents, enjoy the absence of stink?
happy coaching!
buswarrior
Quote from: Bustle on October 23, 2021, 09:46:46 AM
I know you guys had many discussions here on this topic about venting. I personally haven't given much thought to venting yet... but one thing is for sure, your vent needs to be higher than the toilet bowl... 60mm fan can pull 12 CFM of air. It's plenty airflow going through 1.5"-2" pipe. If you are pulling air out, you also don't want any negative pressure in the tank either, so you need an air inlet. Traditional RV tanks only have 1 inlet/outlet. However, different school of thoughts on this. Do you aerate your tank or not? (rhetorical) I think they are called holding tanks, and not septic tanks for a reason. The "inlet/outlet" is not there to vent, but to let gases escape when you put content in the tank, otherwise, you'd get burping back into the coach. While a fan sounds like a great idea, it could be bad idea, as you would be aerating bacteria, and promoting faster decomposition of your tank content. There is a reason why they put formaldehyde in those black tank treatment/odor reducers.
I believe we will get zero smell coming out of the toilet with the macerator toilet I posted, unless there is a defect in the toilet. It's going to be impossible for tank air to escape out of the water trap it has self contained.
Downside? $600 for the plastic throne, and 12v/24v...
$600 they must make different models of the Temca or I really got screwed, I ordered one for my sons RV that sucker was over $2500.00 for his replacement Thetford with shipping
And at the end of all the fans, chemicals, and latest no latest no stink gadgets, before you winterize - fill tanks with water and 1/2 gallon of ZEP Orange degreaser. Wait 2 days, drain, say a little prayer, and you will be ready for spring!
Way too much misinformation about this. If you know the facts it's pretty easy. Municipal sewers are not particularly stinky. Why? because there is air in them.
I haven't checked but it is likely that the gases created by aerobic breakdown are just your average atmospheric gasses for the most part, heavy in carbon dioxide. So if there is ANY airflow through the tank they will waft away in the breeze, which will keep oxygen available. Cut back to one vent only and you insure stagnation of the air, depletion of the oxygen, and the onset of anaerobic breakdown and the creation of heavier compound molecule stinky gasses that are harder to vent out the roof. All of which leads to odors in and around the RV.
So do yourself and those around you a favor. Plan and arrange your vent lines to promote natural airflow through your waste tanks. There are many ways to do this and a fan isn't necessarily the best approach, although it could be helpful. Bear in mind that the stinky gasses are corrosive whereas the ones produced by aerobic breakdown are less so. The packaging of a bilge fan makes it easy to plumb into a vent line using standard fittings and the larger than line diameter and design of the fan blades will be no impediment to airflow when not running. Also bilge fans are typically more resistant to corrosion. So it makes a handy supplement that is easily installed in a vent line and is going to be pretty durable. Connected to the bathroom light, it will cycle whenever someone is in the bathroom, which is often enough to keep fresh air in the waste tanks, even if the vent lines are a little contorted or undersized.
Now how do you get natural circulation? First, at least two reasonable sized vent lines of say 1-1/2 or 2" diameter. Next run them to different outlet locations to help the air flow through. You could run one high and one low and rely on heating or cooling of the air in the lines to cause convection flow. You could put one on each side of the bus with a directional outlet meant to take advantage of any breeze. You could use one of those devices that go on the end that is supposed to convert any passing breeze into suction. Generally each of those will work some of the time, and some of the time may be good enough. A separate vent system for each tank would probably be best, as the quality of the discharge from the vent system (and there WILL be a discharge) will depend entirely on the volume of the flow.
Jim
Treatment plants use the digester system there is no Oxygen or air present to do the bio break down then they use the bio gas to complete the process,that process would be tough to do on a bus
The treatment plant is a Looong way from the municipal sewers. And even those do use aeration to introduce oxygen into the effluent. Those Rotator things you sometimes see churning up the water.
Now on the subject of aeration, it seems to me that is adding an unnecessary level of complexity where none is really needed. I'm sure it could help, but it could also turn into a maintenance nightmare. These liquids are considerably more corrosive than simple water, and you also add the potential for clogging and obstructions. Plus they would tend to make noise and use energy.
Jim
Quote from: luvrbus on October 24, 2021, 10:54:42 AM
Treatment plants use the digester system there is no Oxygen or air present to do the bio break down then they use the bio gas to complete the process,that process would be tough to do on a bus
Ah but if it was methane digester it could help get you down the road LOL!
another subject with over thinking. Mount the tank, vent through the roof. Next subject.
Quote from: chessie4905 on October 24, 2021, 12:28:41 PM
another subject with over thinking. Mount the tank, vent through the roof. Next subject.
x2
Not really. A secondary vent can make the difference between making bad gasses and not making them. Like everything else on the bus, thinking through the consequences of your actions can have a fairly dramatic effect on your comfort level later on.
Jim
how about a charcoal filter or compress it and feed to engine on highway.
Bustle -
My MCI had a single, 100g grey/black tank that was oriented E/W along the back wall of the rear bay, offset to the passenger side, as the compartment was shared with the genset on the driver's side. (Drain line ran thru the genset sound box!) Anyway, the 1-1/2" vent for the tank came out the top curbside rear corner 2" into an elbow pointed at the curb, another 2" length of pvc, then into an elbow pointing to the rear of the coach. From there, another short piece of pipe took the vent line thru the rear bulkhead into another elbow pointing down, with a final piece of pvc, this one cut at a 45ยบ angle facing backwards, that ended just slightly below the bottom of the floor. In the four years and 45K miles I owned that bus, only one time did we ever smell anything around the vent's exit. However, we would get the stink when flushing the toilet sometimes. This tank, like most others, got it's fresh air thru the kitchen, bathroom and shower drains.
My current coach has 60g black and 90g grey tanks. These are both vented thru the roof, the one on the passenger side is for the grey tank, the one on the driver's side is for the black. The curb side vent goes up in the back of the washer/dryer closet, the black tank vent goes up thru the back of the bathroom vanity and medicine cabinet, adjacent to the ducting for the galley's CruiseAire A/C. Like the MCI, the grey tank gets it's fresh air from the sinks and shower drain, whereas the black tank gets it's fresh air from vents cleverly concealed by the bay handles on both sides.
FWIW & HTH. . . ;)
Quote from: Bustle on October 21, 2021, 07:34:03 PM
In our original floor plan the RV type toilet was going to be right above the bay. Since we got a 40ft bus instead of 45ft bus as planned we had to re-do the floor plan. We have to sets of bunks, another single, and a pull out couch. Enough sleeping space for 7.
Bustle -I have friends with a 40' Eagle that sleeps 8 - Mom & Dad in the back bedroom with an E/W queen bed, three sets of two-high 6'6"-long bunks along the passenger wall with storage drawers at the bottom equivalent to another bunk height, a full bathroom on the curb side with the galley in front of the bathroom. There's a jack-knife sofa behind the driver, a copilot seat and a dinette round out the curbside interior. They lived in the coach full-time, home-schooling along the way until the two oldest (twins) graduated from high school. Now they're in a stick 'n brick abode, and the Eagle is just used for weekend getaways.
All that to say that with a little careful planning, you can set up a 40' coach for a large family and still keep the toilet right above the black tank, thus reducing the risk of a crappy situation if the plumbing from the back wall of the bus to the tank develops a leak!
FWIW & HTH. . . ;)