Water running uphill..?

[BradKW]

Getting to placement of kitchen sink and I realize that the drain line will run around 6 feet with an uphill pitch.

The house-building side of me is appalled...but maybe that's just how it is in mobile plumbing?

 

[LeeRevell]

Park on a slope?

 

[SternWake]

I hate it when physics ruins my day, and forces me to yell and shake my fist at an inanimate object that dared to defy my desires


The worst part is, those objects just sit there and do not respond.

 

[Phantom Blooper]

I am no plumber so you may have to ask masterplumber...

However all I know is hot water on left...cold water on right...

And shiat don't run up hill.....I would say that this holds true for water drainage also.

 

[TMG51]

How will it run uphill? Your tank is lower than your sink isn't it? I say you have to figure out how to pitch it correctly.

 

[GotSmart]

Power flush.  Hit it with a blast of compressed air.  

 

[VanKitten]

Yeah, that's not going to get past the building inspector. Oh..wait...no building permit...right?
Still, I would not count on the laws of gravity to be suspended.

I do like the idea of moving a few feet and slamming on the breaks. It would be fun just to explain it to the spectators.

 

[BradKW]

How will it run uphill? Your tank is lower than your sink isn't it? I say you have to figure out how to pitch it correctly.

Yes, tank is easily 2.5' to 3' lower than sink, so I guess water would certainly end up there instead of backing up into sink. It's the in between that pitches the wrong way due to front of truck being about 3" lower than rear. So there would always be water held in the line.

If this were a house, there's no way I'd even consider doing this, but I'm not sure how much it matters...

 

[Gary68]

sink,ptrap,45 and diagonal to tank,probably not the clean square and level you want but i think drainage function is more important

 

[TMG51]

Yes, tank is easily 2.5' to 3' lower than sink, so I guess water would certainly end up there instead of backing up into sink. It's the in between that pitches the wrong way due to front of truck being about 3" lower than rear. So there would always be water held in the line.

If this were a house, there's no way I'd even consider doing this, but I'm not sure how much it matters...

What?

You have 2 feet to work with, the "in between" will pitch whichever way you pitch it. :huh: Like Gary said run it diagonally if you have to. You don't want water and food particles sitting in there all the time.

My shower drain was run with very little pitch. If I park with the back weeks even slightly higher than the front, the shower won't drain. I plan around this but on the rare occasion I get in the shower without parking right the water backs up near the top of the pan before I'm finished and I have to carefully drive to an incline for it to drain. I can't imagine why you'd want to have your sink not drain even when parked level.

 

[BradKW]

Good point about food particles, hadn't thought of that. Problem is that drain line needs to cross the floor, so getting a pitch on it there can't really happen. I might need to swap tank placements around.

I might be able to cross to tank underneath the box, but that kinda kills my idea of keeping all water lines inside to make future winter travel workable with tank warmers. But that's not really a big priority, just an idea. So the other thing with crossing below the box would do is the drain line would enter near bottom of 40 gal gray tank. Need some help on physics here...is that a problem?

 

[jimindenver]

Well yeah. As the water in the tank built up it would force the water back up the pipe. Eventually the water wouldn't have enough weight to force its way into the tank. Put the sink above the tank.

 

[TMG51]

The water in the pipe would be at the same level as the water in the tank.

 

[Gary68]

your inlet needs to be on the top of your tank,you also need a p trap which will hold water preventing gasses to come up your sink and you will need a vent line on the top of your tank to let the gasses out

 

[DannyB1954]

You may have to pump it into the tank. Some homes have a basement toilet that is lower than the home's drain line. They use a pump.

 

[Dennis]

I'm trying to visualize your build and if that is the way it would be if parked level you could raise your sink and build a boxed in step up. That would give you a sunken living room. Of sorts. Or might be one of those times you need something like a macerator pump before a tank instead of after.

 

[karl]

If you enter the tank at the bottom any sloshing is going to try to geyser into the sink....the trap MAY stop it, but do you want grey water coming back into the sink or worse- all over?
Of course there is the previously mentioned issues of freezing and sediment in the line.

My suggestion is move the sink, or move the tank.

Another thought is to have a small grey water jug under the sink and manually dump it more frequently than you had planned....

 

[masterplumber]

Well you could pump it, but I always try to avoid that. Just one more mechanical system to break. One thing that may help is you can buy a compact trap with a drain hose attached at an RV supply. They are usually listed as a pop up sink drain and screw directly onto the sink strainer so you eliminate the height of the tailpiece. If you go to my cargo trailer build I think there's a picture of mine in there someplace. Other than that, I'd relocate things until it works. No sense being g so tied to a layout that it causes the basic mechanics to not work. I'm always a fan of form following function.

 

[ArtW]

the basic problem seems to be the rear of the vehicle being 6" higher than the front, so just carry a sumo wrestler on the rear bumper at all times, problem solved
Sorry, couldn't resist

 

[GotSmart]

the basic problem seems to be the rear of the vehicle being 6" higher than the front, so just carry a sumo wrestler on the rear bumper at all times, problem solved
Sorry, couldn't resist

So when you need to use the sink, he jumps off and  lifts the front by the bumper?  

You need a Trunk Monkey.

https://www.youtube.com/results?search_query=trunk+monkey+commercials