rear toilet to tank run?

[robertglines1]

Time has come to plumb rear toilet to utility bay..Toilet is approx 3 ft from rear of bus-bedroom floor is raised 8 inches to allow for dual slide mech.(raised roof) so was thinking about running the 8ft with 5 inch drop from toilet..so will this be ok with a RV toilet??or do I need to do something different?separate holding tank?macerator  pump? ideas or observations as the rear bath is a done deal. Bob

[luvrbus]

 Bob,won't work with a RV style toilet not enough water you'll need a air flush or one of the marine vacuum type  been there 


good luck

[ruthi]

Bob, we got a lot of great advice on this subject from Fred Hobe in Florida. Maybe give him a call, he loves talking bus.

[cody]

Now you've got me confused bob, arn't all toilets to put your rear on? 

[Len Silva]

The common wisdom is that it won't work, but I have personal knowledge that it will.  You will need to use a lot more water per flush, but it will get there OK.  More critical than the length is the number of fittings.  Keep the bends to an absolute minimum.

Now, if boondocking and water conservation are an issue, all bets are off.

[scanzel]

My toilet will not be directly above the holding tank, it will be about 3 feet away with a 45 degree slope into the tank. But I found a 3" pvc 45 degree connection that has a 1 1/2" side connection. Since my showere will be next to the toilet, when the shower is used it will add extra water to that 3 foot pipe and flush out anything that may have not made it to the holding tank.

[Joe Camper]

We have a Raritan macerator toilet that is in a rear bathroom 2 or 3 feet from the very rear of the bus.

The toilet discharges out the side and then up on top of the OTR A/C duct that runs front to rear.

It goes forward all the way to the plumbing bay first bay forward of the drive tires.

The drain pipe lies flat on that duct we have no issues it works great.

The bus also had a drivers head directly behind the drivers seat that was the same.

The drain for the kitchen sink that is also at the rear runs on top of that same duct, running up the other side of the bus and it and it does not have the help of a pump like the toilet to flow but also never gives us any trouble. Go figure

[luvrbus]

Bob, you really don't want that much slope on the toilet 1/4 per ft max works best most of the time with the greater steep slope the water runs off and will leave the solids 



good luck

[kyle4501]

If water useage is not an issue, use plenty of water with each flush & you should be fine with standard household drain plumbing practices.

If you desire to minimize water useage, I'd suggest an auxiliary holding tank directly under the toilet that drains to the main tank via a valve. The smaller this tank is, the more often you'll have to dump it into the main tank - may not be an issue if its dump valve is easily accessible.

BTW, it is the paper that causes the majority of problems of things sticking to the piping & causing valve seals to leak.

[TomC]

My toilet is on the right side of the bus (my bathroom is built around the rear door of my transit for entrance from the outside if need be) and my holding tank is on center line.  I have about a 3-4ft run to my tank.  The only time it got clogged was when my wife first traveled with me and was trying to save water (bless her heart).  A bucket of water solved that.  Granted you can flush an RV toilet with about a pint of water.  When you have a bit of a run to the tank, just pre-fill the toilet with about what a house hold toilet would have and it flushes just fine.  I frankly don't know why everyone continues to preach that you must have an RV toilet over the tank!?  On my truck, I'm using the same thing-except it is a longer run.  Just have a good slope on the pipe and will be OK.  After all-at your house-how long of a run is it from the toilet to the sewer connection at the street? Good Luck, TomC

[robertglines1]

going to try with 3 inch pipe but reduce the fall to about 2 1/2 inches will use  slow 90 's and tie shower and sink in rear bath in same run. Thanks for come back. the sink and shower can be plumed easily to flow thru the toilet outlet(just below) so should help keep line clean..thanks again for help...Bob

[kyle4501]

I frankly don't know why everyone continues to preach that you must have an RV toilet over the tank!? 

Over the tank is only a requirement if you wish to take advantage of the minimal water use feature.
(At a pint/ flush, you will get 8 flushes for each gallon of water - should be easy to do the math.)
If you are using full hookups when you camp, water conservation isn't much of an issue.
If you like to have the freedom that comes from not being tied to full hookups, then water conservation is one way to extend your time between hookups.
With 4 of us using a 30 gallon black tank, water conservation allows us almost a week before having to dump.

To each their own.
It is easier to make a good choice when you know the options. 

[luvrbus]

TomC no one is preaching to Bob I just answered a question a 8 ft run with 5 inches of slope will cause him problems why cause your self problems he may or may not want to pour water into the toilet to flush his each to his own



good luck

[TomC]

If in doubt about a long run to the black tank, then use a macerator toilet.  But personally-that's another relatively complicated appliance to worry about.  Good Luck, TomC

[gus]

There is no problem if a toilet is not directly over a tank. This is a myth.

My commode is on the opposite side of the bus from the tank (one tank only). The sewer pipe passes forward into the next bay, then across that bay back into the rearward bay and then into the bottom of the waste tank!! It has very little slope anywhere!! And there are two 90* Ls in the line??

I don't think a lot of slant will matter, but I don't know that for sure. It would seem to me the solids would move faster but that may be wrong. Sort of like a water slide, so to speak!!

This toilet sewer pipe is about 12' long and is also connected to the kitchen sink and shower near the commode!!

According to everything I've read on the forums this won't work, but it does, even on an opposite slanted parking spot?? My setup violates all the rules laid out by the naysayers on the forum.

I probably wouldn't have done it that way but it was on the bus when I bought it but works fine.

The only thing I can figure that makes it work is that we always use plenty of water to flush. I don't mean great quantities, just a little extra. I believe that the more water in a black tank the better.

Long may even be better because you aren't exposed to the whole black tank surface every time the toilet flapper opens. Since my sewer pipe goes into the bottom of my tank the only surface area my toilet sees is whatever is in the drain pipe.

I also have a tank vent which makes a loop above the tank then back down through the floor. I'm not recommending you do this because the code police will get on my case, but it works for me and a few others.