Community Forums

Romer1 · 12-22-2019, 10:08 AM

Had a random thought this morning in the shower. Why do RV's have two holding tanks, but sticks and brick use same pipe for all waste? It all ends up in same place when you dump, so why two tanks?

Tha_Rooster · 12-22-2019, 10:33 AM

Maybe so when it backs up you don’t have poop overflowing in shower.

IBTripping · 12-22-2019, 10:48 AM

You're not supposed to think in the shower; you're supposed to sing!!!

saddlesore · 12-22-2019, 11:09 AM

Several reasons..
Way back when...one was allowed to let the gray tank drain onto the ground when camping, and the black tank had to be disposed of into a sewer.
Now, on most of the current production RV's, there just isn't enough room underneath for one really big gray/black combination tank that will drain solids/liquids properly .. so they still split them up to make everything fit and still work (somewhat) correctly ...

The only RV's that I know of that have gone to the single combination black/gray tanks on some models, are the Foretravel, Newell & Provost conversions..

brandss · 12-22-2019, 11:26 AM

Thats an interesting thought. I'm not what the real answer is but I like Roosters answer.

Nudge · 12-22-2019, 11:40 AM

Ummm...cause’ RV’s move and can travel?

Jayco19 · 12-22-2019, 12:09 PM

It's more of a space issue with today's rv's. I have 2 gray and 1 black tank on mine.

scenic route · 12-22-2019, 03:14 PM

I guess weight and balance could be part of the equation. Our last coach was a bath & a half with two gray tanks(40g ea.) and two black(also 40g ea.)along with a 60g fresh water tank. Even if those tanks(B&G)were combined, that's a lot of weight(8.3 # per g.) that should be balanced out.

Old-Biscuit · 12-22-2019, 05:09 PM

Quote:

Originally Posted by saddlesore

Several reasons..
Way back when...one was allowed to let the gray tank drain onto the ground when camping, and the black tank had to be disposed of into a sewer.
Now, on most of the current production RV's, there just isn't enough room underneath for one really big gray/black combination tank that will drain solids/liquids properly .. so they still split them up to make everything fit and still work (somewhat) correctly ...

The only RV's that I know of that have gone to the single combination black/gray tanks on some models, are the Foretravel, Newell & Provost conversions..

This ^^^^^^^

I have 1 black, 1 grey and 1 galley
BUT I can Combine both greys or all three because I added an extra dump valve that allows me to do so.
Great for when boondocking

airshot · 12-22-2019, 06:32 PM

In most cases the gray fills long b4 the black tank, if it was one tank, you would be empting the tank more often. I empty my gray tank 3x to 1x on my black tank, saves on chemicals ...If an emergency comes up I could allow a small amount of gray out but never the black tank! If all in one tank energencies would really be emergencies!!