Holding Tank Question

[Jlb27537]

Hi All,

We have a 2014 3150RL. It has 2 gray tanks. The shower, bedroom sink and washer/dryer drains into one below the front storage area. The second tank is kitchen sink only. It is in the main frame rail area by the wheels. The second tank is mounted higher than the shower tank.

The brochure shows 93 gallons of gray storage. I have the Valtera 3" valve on the output of the drain pipe. I realize the sink tank is higher than the shower tank but is lower than the shower floor, so has anyone closed the add on Valtera valve, opened the 2 gray valves and let the shower tank back up into the kitchen tank.

We are in a site with water and electric. The shower tank is almost full and the kitchen is empty.. Thinking the shower tank can back feed the kitchen tank???

Who has tried this?

Thanks Jim

 

[Kenneth Deiss]

I have not.But I know others have done this Mod!

 

[HOOK-MOC]

I had the outside valve on the 3455, basically the same as yours, and always let both grays back flush the black. Your idea sounds good to me.

 

[Jlb27537]

Larry, I am not trying to back flush the black. I am trying to use the kitchen gray tank for shower water by back filling.

Jim

 

[vangoes]

Jim,
I have some friends that have done this on SOB's....it typically will work until the pressure (water level) becomes equalized between the two tanks which is somewhere short of full for both tanks.

 

[takpak]

I have done what you are thinking about/suggesting on our 2011 3400. Same situation, "bathroom" grey is lower than the kitchen tank, but it works. I had to install the shutoff valve on the main outlet of the sewer line so the two tanks would "cross over". If we are somewhere without sewer connection, I close that main line valve, open both the bath and kitchen valves, and let the water build up in both. One thing, because the bath tank is higher than the kitchen, the bath tank will fill up first. It will stay that way (showing full) the whole rest of the time. Then what you need to watch is the level of the kitchen tank. When it gets full, you really ARE full. I'm not sure on your model, but on ours, if I forget to watch the level, because the shower and sink are higher than the kitchen sink, if you overflow it, you could have shower water coming up in the kitchen sink. Not as bad as black water, but not pleasant, either. So, you can do it, but watch your levels carefully. Also, NOT recommended to "backwash" the black tank with that water. Tried it once, was not pretty. Didn't blow anything, but the odor that came out of the vent on the roof was pretty bad when that water surged into the black tank. Plus, there is always the possibility of getting a backwash of black water into the grey tanks. So, not a good idea. Keep the black one separate. Doing what you want to do, we can go 4 days plus on the grey tanks. The black tank we can go 7 or 8 days easily. Hope this helps.

 

[DQDick]

I agree with Terry and did use them as one during an emergency. Would not, as Terry says, open them to the black tank for any reason. The possibility of cross contamination worries me too much.

 

[Carl n Susan]

I used to share the two tanks all the time on my 2005 Montana. The tanks were all on the same level and it worked well. I will not do it on my current Montana with the split level installation of the tanks. The top of the shower tank appears (to me) to be lower than the bottom of the galley tank. Consequently, the shower tank will fill completely before storing "water" in the galley tank. Given the number of folks here with leaking tank problems, I don't want to over stress the top or the bottom (or even the sides) of a tank.

We routinely go 10-12 days without filling the tanks using water conservation techniques. By then we are ready to move and dump along the way.

I don't understand the "cross contamination" concern of using the galley or shower tank to back flush the black tank. It's not like anyone has potable water in any of those tanks. In fact the galley tank often has a worse odor than the black tank.

 

[Jlb27537]

We did not have to try and back feed the tanks this week. When I dumped I did the black first. No odor's. Next the galley, whew... then the shower, no odor's.

Yes, the galley was by far the worst in the odor department.

Jim

 

[moutard2]

Not quite on topic but are you sure that your washer/dryer drains into a holding tank? It's my understanding after reading numerous MOC posts on the subject that the washing machine drains directly out of the trailer and that you should always be connected to a sewer system before using your washer to avoid nasty surprises. Perhaps the 2014 models are different.

 

[bncinwv]

quote:Originally posted by moutard2

Not quite on topic but are you sure that your washer/dryer drains into a holding tank? It's my understanding after reading numerous MOC posts on the subject that the washing machine drains directly out of the trailer and that you should always be connected to a sewer system before using your washer to avoid nasty surprises. Perhaps the 2014 models are different.

It is totally model and in some cases year specific. For instance, the new 3850 which has the washer/dryer in the kitchen slide apparently drains into the galley tank (I was told this, but have not confirmed, but it makes sense). Our 2007 3400 and 2011 3750 did not drain into any tank.
Bingo

 

[jswharton]

I do that in our 3100 but have the opposite problem, galley fills before grey tank. 93 gal of grey capacity and I believe h galley is smaller. The Gary and black tanks sit right next to each other and extend under the basement. Based on what I could feel the grey and black are the same size @ 50 gal.

Water will seek to equal and on my unit I think they galley would be high enough that the water would probably be half way or more up the shower drin pipe. Thy galley drins quickly ino the grey

 

[Jlb27537]

quote:Originally posted by moutard2

Not quite on topic but are you sure that your washer/dryer drains into a holding tank? It's my understanding after reading numerous MOC posts on the subject that the washing machine drains directly out of the trailer and that you should always be connected to a sewer system before using your washer to avoid nasty surprises. Perhaps the 2014 models are different.

Yes, I am 100% sure it drains into the shower gray tank.. Wife did laundry, all valves closed. Water was in the bottom of the shower and closet.

Trust me, I know where it drains on my rig...

Jim

 

[2Wanderers-MOC]

Something to consider. I, at first thought this was a pretty good idea, especially when camping in locations that had water and electricity, but no dump. However I then realized that to equalize the water between the two gray water holding tanks, the water has to pass through the common discharge pipe (which is also common to the black water tank). Did I really want either of my gray water tanks exposed to the same discharge pipe as my black water tank. This would involve constant leveling between the two tanks and not the quick rush of outflow that occurs when dumping. If we had a pipe that ran between the two gray water tanks without being exposed to the black water residue, I might reconsider. What do you think!