Add black tank

[Crows Nest]

Our 21NE has only a 13 gallon black tank. I’m thinking about adding another tank and have made a rough sketch of a proposed concept. I’d appreciate any feedback.

 

[Donna D.]

I don't see a pipe into the second tank. I do see the discharge from it however.

 

[Centex]

Suggest it's time to advance from the provided 'concept sketch' to a dimensioned scale drawing of the same view based on actual frame / chassis and pipe / fittings measurements.

Methinks that simple reality-check will reveal a lot regarding feasibility and provide a basis for meaningful review / comment.

 

[7Gentex]

Guess you missed all the "fun" in 2020 and before when ETI had the E19 & 21NE black tank published specs at 19/22 gallons, though it wasn't..................

Good luck sir - following for options..........besides a 21C, 5.0TA or a 23.

 

[Ron in BC]

If you were doing that with grey water it'd probably work because water flows easily. It would fill the lower tank and then the top tank.

However considering the consistency of the contents I think that you could end up with an immovable mass in the wrong spot that created a blockage.

Definitely a second thought is required for this project.

Ron

 

[Crows Nest]

Yikes! That would be a big problem. As regards Donna D’s comment, I would replace the elbow from black tank to outlet with a “T” connector.

 

[John in Santa Cruz]

we run out of fresh water and grey holding long before we run out of black tank capacity. We can stretch the water+grey a full week of dry camping, the black can go 2+ weeks.

I guess there's always one of these...
https://www.amazon.com/Camco-Gallon-Portable-Holding-Steerable/dp/B083N2WSXY

but full, that would weigh close to 300 lbs, so other than rolling it on flat pavement, it would be brutal to have to transport to a different site to be dumped.

 

[Crows Nest]

The NE has only 13 gallon black tank. What model do you have?

 

[John in Santa Cruz]

The NE has only 13 gallon black tank. What model do you have?

ah, righto, I have a 21 classic. I don't remember how big the black tank is

 

[Ron in BC]

I would replace the elbow from black tank to outlet with a “T” connector.

I don't want to be too graphic but you know how a pyramid sometimes forms? The tank contents are a suspension of solids and liquid. Forcing them into a situation where it's easy for the liquid parts to rise and the solids to settle out, probably around something like a Tee would result in a blockage.

There may be a way of getting good flow etc. through a second tank but what's proposed so far doesn't seem the way to go.

Personally I think the best way to go is a portable tank if extra storage is required.

Ro

 

[Steve Clark]

I don't want to be too graphic but you know how a pyramid sometimes forms? The tank contents are a suspension of solids and liquid. Forcing them into a situation where it's easy for the liquid parts to rise and the solids to settle out, probably around something like a Tee would result in a blockage.

There may be a way of getting good flow etc. through a second tank but what's proposed so far doesn't seem the way to go.

Personally I think the best way to go is a portable tank if extra storage is required.

Ro

Plus, The black tank uses gravity to drain through the exit valve. The low profile of all Escapes places the existing black tank lower than most other RVs on the road. Adding a second tank below would make it nearly level with the valve, and all gravity would be lost. I don’t see solids draining at all!

 

[GinoandLinda]

Sounds like a great application for a compost toilet

 

[Crows Nest]

We have a 15 gallon shuttle. Unfortunately the outlet on the trailer is too low for the shuttle. I put on smaller wheels and it looks like it’s going to work. We have folding 10’ ramps that I use to put our 100 lb generator into the truck. Hopefully I’ll be able to push the 120 lb shuttle up the ramp too.

 

[hugh]

We have a 15 gallon shuttle. Unfortunately the outlet on the trailer is too low for the shuttle. I put on smaller wheels and it looks like it’s going to work. We have folding 10’ ramps that I use to put our 100 lb generator into the truck. Hopefully I’ll be able to push the 120 lb shuttle up the ramp too.

FWIW, the outlet on my 21C is also too low to "gravity" drain from my onboard tanks into my 36 gallon Rhino tote tank. But my macerator pump works great as a "transfer" pump! I hook the empty tote tank to the hitch, and then use the macerator pump to transfer gray water from the Escape tanks to the tote tank.

 

[hugh]

we run out of fresh water and grey holding long before we run out of black tank capacity. We can stretch the water+grey a full week of dry camping, the black can go 2+ weeks.

I guess there's always one of these...
https://www.amazon.com/Camco-Gallon-Portable-Holding-Steerable/dp/B083N2WSXY


but full, that would weigh close to 300 lbs, so other than rolling it on flat pavement, it would be brutal to have to transport to a different site to be dumped.

That's the one that I have. I use it almost daily when we're beach camping at the state parks. (lots of showers, water hookups, but no sewer hookup).


FWIW, the 300lb isn't as bad as it sounds. If you're lifting it full, you're typically just lifting one end onto the hitch while the other end stays on the ground. So maybe ~150lb actual lift. The version you linked has the optional "dolly wheels", so I guess no need to lift it at all. I'd worry how well those small front wheels would hold up to being towed though.



That said, I wouldn't want to try to drag this thing to the dump station any other way than having it attached to the hitch.

 

[Thane-ESC]

I added a 13 gallon auxiliary tank to my 2006 17b and it has worked well for us. The tank can store black and/or grey water. Usually we just use the extra 1.5 gallons or so of storage space due to the larger manifold of pipes that hook everything together. Here is a link to a description of my installation.

https://www.fiberglassrv.com/forums/f56/escape-trailer-auxiliary-tank-30273.html

A few years ago I encased the tank in a built-up metal cover that is bolted and epoxied to the cross frames for added strength and protection from road debris. This summer I am changing from 14 inch to 15 inch rims for a little more clearance. The auxiliary tank has worked well for almost 17 years.

You would need a vent line for your new tank and I think the water would flow better into and out of the tank if the tank hung low enough such that the plumbing did not require water to flow up and into the tank.

My auxiliary tank is totally isolated from the rest of the system by a normal dump valve and the tank is not used most of time. When I use it, I open the gray or black tank dump valve and the auxiliary tank valve to fill the auxiliary tank as needed, then I close all valves to isolate all tanks for further camping time and transport. An added dump valve downstream of all other dump valves is needed for my system.

 

[Crows Nest]

Wow! I’m impressed. I don’t have the patience or courage to undertake such a detailed project. Kudos to you! Beautiful work. For now I’ll stick with the tote tank. It would be great if I could carry a full tote under the trailer instead of in my truck bed but there’s just not enough clearance.

 

[7Gentex]

Hmmmm.............

Maybe a tank underneath the floor / directly under the existing black tank between the frame rails that is "top fed" (yuk!) directly by the existing black drain - straight shot down to the aux tank - then sideways from the bottom side of the aux tank to the drain valves..........an aux tank there should "recieve" the solids directly due to the bottom drain design of the existing black - appears there is room on the E19, which is very similar to the 21E. Having the "high lift" may be a plus for this idea.............???

 

[Crows Nest]

Ok, new idea. We’ve been successful using macerator into shuttle in the bed of truck and driving it to the dump station (if available) and emptying with slinky from back of truck. It’s just time consuming going back and forth. So… thinking of additional tank adjacent to existing under the bench with it’s own outlet and vent pipe plumbed into existing one. Use macerator to transfer into auxiliary and drain it with slinky at dump station.

This could effectively double our black tank capacity.

 

[Donna D.]

Back in the day of using my 16' Scamp and it's itty bitty 9 gallon black tank, I made one of these. I can pick it up and dump anyplace black water is allowed. I bought one of those old luggage totes (with wheels) at Good will and can cart the tank by hand. This is at least 15 years old, still works as designed. I've used it for gray water too...