Keep Your RV Gray Tank Open? Closed? How About BOTH?!
Leaving your RV’s gray valve open when fully hooked up allows you to take long showers without worrying about dumping or filling up the gray tank. But what about sewer smells that can come up from the campground sewer system? Here’s how to get the best of both worlds!
FEATURED & RELATED PRODUCTS AVAILABLE ON AMAZON:
Slunky sewer hose support: http://amzn.to/2DVAC7l
360 Siphon Vents: http://amzn.to/2EFuMby
Clear Sewer Elbow: http://amzn.to/2DVAzIH
Clear Sewer Adapter: http://amzn.to/2FHNO0j
20′ Heavy Duty Sewer Hose: http://amzn.to/2E8BKYO
One of the luxuries of staying in a full-hook-up campground is the ability to use water freely for showers, cooking and washing dishes. The sewer connection allows you to leave your RV’s gray valve open, so water can run right out instead of filling up your gray tank.
Of course the black valve can NEVER be left open, since “solids” will build up in the black holding tank when the “liquids” run out. But there’s a fair amount of discussion about the gray valve. Some people recommend that you should never leave the gray valve open either, as it can allow odors from the park’s sewer system up into your RV.
Of course leaving the valve closed means having to pay attention to the water level in the gray tank, and dumping it every few days. Seems like a shame to have to do that when your RV is connected to a sewer line, especially when you’re staying in a full hook-up site for an extended period of time.
Since the drains under every sink and shower in an RV are equipped with a p-trap, leaving the gray valve open shouldn’t allow odors into the RV. The water in the traps blocks odors from entering the RV’s living space. Long periods without use can allow the water in the traps to evaporate, and driving on twisty or bumpy roads can cause it to slosh out. But both of these situations are easily remedied by running a small amount of water down each drain.
There is, however, a pipe with a direct connection to the sewer hose…. connecting to the tank vents on the roof of the RV. This can allow air from the sewer system to come up through the roof vents. If you’ve ever smelled sewer odors in a full hook-up campground, it’s possible that someone’s RV is venting the park’s sewer system out through their roof.
In a recent RV Travel newsletter, we read about the simplest way imaginable to enjoy the luxury of a full hook-up RV park. You can leave your gray valve in the open position so water runs right down the drain. You don’t have to pay any attention to how full your gray tank is and you don’t have to dump it every few days. But there’s no chance for sewer odors to escape either. It’s the best of both worlds.
Watch the video to see how we did it!
Please use your full hook-up powers responsibly and don’t waste water!
The piano music is my own performance of Scott Joplin’s Maple Leaf Rag from 1899.
WONDERING WHAT’S THE BEST GEAR TO USE ON YOUR RV?
Here’s all of our favorite equipment that we use ourselves and recommend to friends:
http://thervgeeks.com/our-favorite-gear/
Join us at http://TheRVgeeks.com for more great RVing content!
Full-Time RVers since April, 2003, we share DIY (do it yourself) RV maintenance, repair, travel, upgrade and operational tips & tricks.
Many RVers are eager to learn more about using, maintaining and caring for their rigs. We hope our experience can help others go DIY, saving time & money, plus the satisfaction of a job well done.
We’re handy RVers, not professional technicians. We’re happy with the techniques and products we use, but be sure to confirm that all methods and materials you use are compatible with your equipment and abilities. Regardless of what we recommend, consult a professional if you’re unsure about working on your RV. Any task you perform or product you purchase based on any information we provide is strictly at your own risk.
We sometimes receive products for evaluation at no cost, and The RVgeeks participate in the Amazon Services LLC Associates Program, an affiliate advertising program designed to provide a means for sites to earn advertising fees by advertising and linking to Amazon.com. But our opinions are our own, you won’t pay an extra penny, and we only link to products we personally use, love and can recommend to friends with complete confidence.
Comments welcome! Thanks for watching! Don’t forget to subscribe! #RVLIFE #RVDIY #RVLIVING #FULLTIMERV #RVREPAIR #RVMAINTENANCE #RVMODS #RVUPGRADES #RVTRAVEL #DIYRV #RVGEEKS
source
You're effectively creating a whole house trap. These used to be common in houses but not any more. They had a problem with accumulation and backups. I guess if you're in an RV, you probably clean that line regularly, but I would be careful if you're planning on staying a long time.
Smart!
I always leave the grey tank open
Good info. Just got an old bumper pull so learning as I go. I don't have a fancy support for line but did have a section on plastic c shaped gutter, could use the 4" pvc pipe too. Elevated the gutter with stones so good flow to sewer and did add that trap loop. I didn't like the idea of just laying the tube on the ground. Bad thing about older trailers is there is no fancy tank level, you have to flush and look.
I have heard mice and rats can work their way into your Gray tank if you leave it open…how would you prevent that ?
I am always telling people to do this. So many assume just because they can't smell it, we can't. However, on warm summer evening when the hot air is park just above us, that nasty smell always makes it's way into my open window to wake me from a dead sleep.
I wish everyone would think of this common sense solution. Along with properly securing their hose to the sewer connection. Ugh… seriously. Especially with today's parks seemingly getting smaller as they add more sites. The park I'm in now is allowing small trailer to use half of a site. I can literally reach out my window and touch the neighboring trailer. I'm not even exaggerating. If he needs me to wash his back, all be has to do is ask. Not that I would oblige. I might pass him my back scrubber. This issue of two RVs just inches apart exacerbates the sewer gas issue. He is in a little trailer and I am in my DRV. Just three feet away at the same level as my bedroom window is his sewer gas vent. Because we are so close, the gases coming out of an ill fitted sewer hose and the vent pipe are not moved or diluted due to a lack of airflow from being too close together. Sure he gets a discount, but I'm the one suffering from his snoring, poor sewer connection, and gases coming out of his vent just three feet from my nose. I dare not complain. The park is full. Bit $110 a night for this is insane. The spaces are so tight my truck is park in an overflow lot a five minute walk away. I'm disabled too. So this walk is difficult despite my younger age.
doesn't make sense to me. seems like you are watching the black tank so no big deal. use the gray to rinse the drain hiose, as i am sure you are all ready aware.
No odors but valve has snapped off when i closed it and then opened it got muddled by a somebody now its broken how can i fix this and who can do the job thanks
Brilliant!
This is an amazingly simple and effective technique, in 30+ years of RV'ing I've never thought of it. Although my RV has only one tank and one valve, so I'm guessing I should continue to keep it closed except when dumping like I always have. Since the trend in recent years is to have two tanks, which would seem to double the costs and points of failure, I'm curious what the advantage is for having two tanks.
Very helpful thank u
What I don’t get is why not flush the black and use the grey to clean it every few days? It’s just two handles you pull. I’d rather save my grey to clean the black out of the hose every 3 days
I learned to shut my gray valve until I fully drain my black tank, then I can flush black tank by draining gray tank and then close gray tank back up fast..I don't leave the black one open full time, just make sure you keep enough fluids in there with some solution to break down the hard materials and your good
Hi
Help me why when i opened the grey water every 3 o 4 days cause we are full timers the black tank show me empty too if i just pull out the valve from the grey water ?
Thanks again allways 👍
Brilliant!
Thanks guys!!!!
Why not just place charcoal filters in the tank air vents
when living in a travel trailer fulltime and through winter in a trailer park, the travel trailer is hooked up to city water and sewer. Is there always maintenance to do on the black water tank?
Really best thing to do is keep the grey tank closed. It's not hard to pull the grey tank valve to flush for 30 seconds every few days and it's good to have grey water available to flush out the hose if you flush the black.
been doing this for years with the hose on the ground but putting a wheel chock under the hose to make the trap
Good thinking. Thanks for the tips.
I've heard others say that you want to keep the grey tank closed even when hooked up so that you can flush the hose after voiding the black tank.
ok for the gray water because there are no solids, but keep the Black water valve closed because the human waste will pyramid and not mix with the water.
I suppose though you would want to return the hose to normal when dumping the black tank?
Also one question that puzzles me is why so many campgrounds charge a fee to dump, but they don't charge to use the flush toilets. I can understand they charge to use the showers since they have to heat the water, but why do they charge to dump when they don't charge for the toilets? Isn't it all the same $hit ending up in the same place? They should give a discount since you brought your own toilet and they don't have to maintain a bathroom house on your account but instead they typically charge more.
Always leave the valve shut so that rats or other animals can't climb up the hose and into the tanks.
How about with two gray water tanks (kitchen and bath?) Should I leave them both open?
Thanks.
Joe
I always let the gray fill up so I can flush the sewer hose after dumping the black tank, but I guess that's just me…
Will creating that artificial P trap on the outside still allow water to flow down to the sewer?
doing this womt effect the ability for solids on the black tank to drain correctly?
Had an idea I never tried. If you add a gate valve to the discharge where you connect the hose. After emptying the black tank, close the added valve and open the grey tank valve allowing the grey water to gravitate into the black tank, then open the added valve. That should help clean the black tank with an extra rinse. Opinions????
Not Legal if your getting technical but in this major California drought you can break a rule for mother nature and run the gray water out at night with a garden hose to the closest tree. Wifey and 2 daughters all have Farrah Fawcett hair so water conservation is a hot topic. Soap is harmless and the little pine tree that is in a struggle to stay alive will appreciate the extra H2O!!!
I did lotsa research on the Wynn poop box and no way am I mixing smashed coconuts to create a compost to carry a box full of poop. See ya Ka flush!
Thank you RV Geeks.
I loved the input, but I have a question. I have an RV. Does leaving the gray water tank open continually cause carpet flooding? Or is it another leak elsewhere….p.s. its in the bedroom
What an easy solution. Thanks for sharing.
Maybe just a reminder to never leave the grey open or the hose p trap position in below freezing temperatures .
tanks! :^D