Holding Tanks Questions #1

[Seangie]

Hey All,

I am getting close to moving onto the next part of our project, installing the holding tanks.  And I am at the point where I need to order my holding tanks....fairly soon.

But...I have a bunch of questions about holding tanks as I have zero experience RV'ing.  I have learned that what makes sense in my head doesn't always make sense on the road so I am going to be posting a few questions about tanks over the next week or so and rely on the wisdom of the board.

Here goes the first one -

For my fresh water tank - I thought it would be good to install a "visual site" by putting a tube in the side of a tank and using that tube for the breather hole (at the top) and drain at the bottom.  To save mental beans I drew a picture -


The breather would be at the top of the tube with a removable hose that would redirect water under the bus when moving (for spillage) and a draincock  would be installed at the bottom to empty the tank if needed.

Feedback?  Good idea?  Bad Idea?

Thanks to all of you!

-Sean

[chev49]

you could do that. i would think that the vent at the top of the tank would take care of the spillage. a clear tube help you see the level of the water unless it got discolored a lot. You also could put in the water level sensors if you have a panel for tank levels.  I think the normal way of hooking up a tank would work fine. I hooked my tanks up with the sensors to read the tank levels at the panel.

[Cary and Don]

Our breather goes back down through the floor for overflow when filling.

Don and Cary
1973 05 Eagle
GM 107
Neoplan AN340

[fraser8]

I have the system you are talking about. A clear hose running from the bottom of the tank and connects to a vent hose at the top. works good as a level indicator, I have a 100 gallon stainless fresh water so it takes a while to use all the water. The site glass (hose) works well and is an inexpensive solution. I can put a picture on if you like.

[Seangie]

Fraser,

A pic would be great.  What size are the connectors in the tank for your setup?

-Sean

[luvrbus]

The bad thing about the clear hose for a sight is in some climates it will grow mold and mildew like crazy they get pretty nasty over time with flowing water all the time it is not bad

[rv_safetyman]

I have "sight tubes" installed on my fresh water, gray water and auxiliary diesel tank.  In each case, I had a fitting installed towards the bottom of the tank and then installed a ball valve.  The hoses are terminated at the vent of each tank. 

In the case of the fresh and gray tanks, I used about 5/16 clear tubing that you can easily get from the hardware store (think vinyl?).  The fresh water tube has not had any significant problem with "stuff" in the tube.  The gray has gotten pretty bad in 6 years and need to be replaced (easy). 

For the diesel tank, I did a lot of looking for clear tubing that would work with diesel.  Finally found some red colored tubing that is made to replicate what we used to use as gas line tubing in the old days (think multiple carbs).  Each time I fill the fresh or diesel tank, I use the sight tube to let me know how full the tank is getting.

They all work great!

One of the absolutely best things I learned from Tom Winterhaulter (BCM workshop several years ago) was to install large fittings towards the bottom of the passenger side of the black and gray tanks and then connect them with the typical dump valve (I had to use one that was smaller than the main valve - maybe 2.5 inches).  What that does is allow you to dump the black tank then go to the passenger side and dump the gray tank ***THROUGH*** the black tank.  Really helps to wash the solids out!!!

Jim

[Iceni John]

I have two interconnected 110 gal Ronco B433 fresh water tanks, and one tank has a simple sight glass (actually it's clear vinyl tube, so I suppose it's a Sight Plastic).   Unless I isolate one tank or park unevenly, it will accurately read the level of both tanks.   I had Ronco spin-weld 1/2" raised FPT fittings in the bottom and top of that tank, and the sight glass connects to both of them, i.e. it's not open at the top, to prevent creepy-crawlies getting in.

Each tank has a 1-1/2" gravity fill in its top center sealed with a Uniseal grommet, and a separate 1/2" threaded vent that has a length of tube running down to the ground.   When water comes out the vent, the tank's full!   I can also fill each or both tanks through the city water connections (one on each side of the bus) that can feed the tanks' 3/4" outlets if I open a fill valve.   Each tank's 3/4" outlet has a separate valve to isolate it if needed.   The left tank also has a 3/4" feed that runs into the main gravity inlet, and this will be used to divert not-yet-hot water back to the tank instead of wasting it down the drain while I wait for it to get hot at the tap.

For my gray and poo tanks I will use TomC's idea of a light shining down through their tops to show how much is inside.   They both have 3" dump outlets, with a third dump valve to allow back-filling the black with gray water.   The gray also has a 1-1/2" dump valve on the right side, for dumping gray water kerbside.   I had Ronco put a 3/4" fitting in my poo tank directly above its 3" outlet, to allow easy flushing of any solids near the outlet.   This will also connect to the transfer pump that moves gray water from its own 3/4" outlet near the bottom of the gray tank, so if my gray's getting full but there's space left in the black I can run the pump for a few minutes to free up some space in the gray tank.

HTH, John

[Seangie]

Jim,

Here is my idea for the flush - The gray tank will be higher than the black tank and I will be able to drop the gray only or drop it directly into the black tank to flush it or make more room in the gray tank. 
 

Not sure how to get the dumps over to the passenger side but this seems brilliant as that is the side on the curb and it would be easier to dump everything on that side.  The PO had already done a bit of work on the bus and I am just taking off from where he left.  Next bus though...its all going curbside

Would dropping the gray into the black like shown would cause black contamination of the gray tank?  Would it be better to have it drop further down into the black tank?

For my gray and poo tanks I will use TomC's idea of a light shining down through their tops to show how much is inside.

What??  No site valve for the poo tank??  JK )

John,

I like the idea of recycling cold water.  We saw this feature on Sean's Odyssey and it just made sense.  I also like the 1.5" gray water dump to curbside.  This might be an add to what I am planning. 

Thanks again guys for all the feedback. 

-Sean

[fraser8]

I tried to take a photo, it read change batteries, so no picture. The process is simple as explained above, T a clear hose into the overflow then have a connection near the bottom of the tank. I used dairy tubing ( http://www.terraflexhoses.com/dairy-hoses-clear ) I have a dairy farm, no cows anymore, just the buildings to store my old cars and bus, the dairy tubing is made so you don't get bacteria build up, there is also a special brush that you can get that is long and made to clean the tubing if something gets in it. Mine has been in use for 4 years without a problem. There are several places that sell it, the tubing from a hardware store isn't the same, dairy tubing is very heavy walled and very flexible as well as food safe.

[Melbo]

The conventional dump side is the drivers side not the curbside.

I'm sure if you have enough hoses and can wind them around and/or under the bus you will be able to get it where it needs to go.

When the bus is settled it is pretty low and the closer to the dump the outlet is the better

HTH

Melbo

[buswarrior]

If the tanks are filling the whole width of the coach, installing valves in order to dump from either side can make life more pleasant in the busy places where you've had to face a certain way for the fuel, and the dump ends up on the wrong side without turning around.

Nothing more fun than the spectacle of other RV's, all driven by folks who can't back up, autos buzzing into the between spaces, and line ups of vehicles in every direction.

Even if infrequently used, in those wild truck stop/service centre/campground dump station times when turning around would be trouble, it'll be worth the doubling of drain valve costs.

Especially if your own tight spot reversing skills are a source of stress.

happy coaching!
buswarrior

[TomC]

My tanks are made by Ronco and are white plastic.  The simplest gauge is to mount a halogen puck light above the tank and when you want to see the level, just turn on the light-course this works best at night-but how many times during the day do you have to check your tank levels?  Then you have no sight tube to leak or discolor or get moldy. I always believe in the simplest way possible.
My fuel tanks have updated vertical ball floats that are very accurate.  Good Luck, TomC

[garhawk]

Hi Seangie,

Our Eagle has 160 fresh and same for grey/black combined.  The fresh tank has a clear plastic hose from top to bottom which shows the water level.  However, it is difficult to read at times, especialy since the plastic has yellowed over time.  Me thinks the answer is twofold:  replace the aged plastic hose AND, drop a small piece of red-painted cork into the hose as an indicator.

While I intend to keep the clear hose indicator at the tank, it would be nice to have the availability of checking the water level from inside the coach. 

[fraser8]

If you have access to dairy tubing or a food grade silicone tubing it won't yellow and will stay very flexible. I have tubing in the milk house that is over 30 years old and still very clear and usable.