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Which Is The Black Water Tank Valve and Which Is The Gray Water Tank Valve On Our RV???

by Carrie
(Isleta Pueblo, NM)

Help! We're all hooked up to dump our 2003 Aurora Coachmen tanks for the first time ... which is the black tank drain valve and which is the grey water drain valve - there is one on the left that doesn't move at all and one on the right that kinda swivels when turned. I have read thru all the manuals given and even tri...ed to find on internet - all I'm finding is "be sure to dump black tank first THEN the gray water tank - none tell which valve is which. Can someone please help before the sun goes down - lol - thanks much!

ANSWER: Greetings Carrie thanks for submitting your question on our Ask An RV Question Page.

First I need to let you know that I have been there and done that. If the valves are not marked there is no way for sure for me to tell you which valve is which. You have a 50/50 chance of pulling the right valve the first time you dump your tanks.

If you end up dumping the gray water first and the black water last, nothing bad will happen the world won't end and your RV will not blow up. The only consequences are that the gray water will not flush out your sewer hose, so you will have run some water down your sewer hose before you disconnect it from the RV parks sewer system to flush out all of the gunk remaining in the sewer hose.

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You are not alone in this dilemma you might want to read the answer I gave to How Do I Figure Out Which Lever Dumps Which Holding Tank On My RV?

OK now it's time to make a choice on which valve to pull first. Just keep in mind those famous words that Clint Eastwood said in the movie Dirty Harry "Are You Feeling Lucky?" Now close your eyes and count 1, 2, 3, and pull a valve!!!

I hope that luck was on your side and you pulled the right one, if not consider it a slightly messy learning experience.

Do you have any suggestions or comments on this topic? You can add them to this page by clicking on the "Click Here To Post Comments" link located near the bottom of this page.

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Happy RVing

RVing Al

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Comments for Which Is The Black Water Tank Valve and Which Is The Gray Water Tank Valve On Our RV???

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Rating
starstarstarstarstar 		Grey galley tank release
by: Anonymous

We have a 2016 Crusader and after asking everyone (to no avail) where in the heck the galley grey water tank dump valve is, we found it! It's to the right of the drain, tucked up under there is the galley grey water tank release. It looks just like the others. You almost have to be on your back to see it. Hopefully this will help a few people out!!!
Rating
starstarstarstarstar 		Tank indicators
by: Anonymous

Answers are all unclear, which one is number 1 and 2 on the indicator panel. Again, when I press "test" on the panel inside my trailer which one is black water and which one is grey water? I want to know should I quit peeing or doing dishes inside my camper???
Rating
starstarstarstarstar 		Which tank is gray water?
by: Anonymous

thanks, but sorry if I was unclear, I mean literally "which tank is called number one" and "which is called number two"...so when we are in the Rig and press the rocker switch and it indicates full, empty or somewhere in-between, we 'know' which tank the number is referring to...I replaced the sewer clean out myself, so I understand the pipe end of things, just trying to make sure we have the indicator panel correct...so, is there a standard like 1 is always black and 2 is always gray or the inverse?
Thanks,
Meredith :)
Rating
starstarstarstarstar 		Which tank is gray water?
by: Meredith

Hello,

We are now confused which tank is our black and which is our gray water on on hood style (1989) monitor panel...thought we knew but circumstances have now made us unsure, any standard labeling here on which is tank one and which is tank two?

Thanks,
Meredith :)
Rating
starstarstarstarstar 		how to tell black holding tank from grey holding tank
by: Anonymous

The way to tell which one is Grey and which one is Black is to look at the size of the drain pipes on each. The larger drain is always the Black valve dump.

I hope this helps :)
Rating
starstarstarstarstar 		Valves
by: Anonymous

If they are valterra valves the black valve 3" will have a black handle, while the grey valve 2" will have a grey handle
Rating
starstarstarstarstar 		Big and Small
by: Ed

The best way to tell is just by looking at them. There are two differant sizes, the bigger of the two is black water and the smaller is gray. He also said that he turned them and nothing happened, he has to PULL straight out on the handels.
Hope this helps

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