Gray water tank & sewer connection

[gastan]

I know that, when hooked up in a site with a sewer connection, the black tank valve should not be left open - - - that the black tank should be left to fill at least 1/2 way before emptying in order to alleviate "build-up".

Is the same true for the gray water tank? Since it is mostly just soapy water (albeit dirty) and there is nothing to build-up, would leaving that valve open cause any problems? How do y'all set it up?

[A32Deuce]

I do that with both tanks. Let fill then dump.

[Chuck_S]

I leave the grey valve open all the time. As noted, it's no more than soapy water. I'll let it fill with shower water just before leaving the site to assist flushing out the black tank drain hose (same hose actually).

I don't flush the black tank as I use an enzyme and oxygen treatment and any residue decomposes just fine. Never ever use anything poison (or blue).

-- Chuck

[madatme]

Leave both valves closed, dump the black first then dump the the gray, reason is you want the gray water with soap to rinse the sewer hose

[Larry0071]

I always do a grey tank pull at 2/3, and that typically is daily while at a full hookup site. But I always will watch the black tank, and every 3-4 days it will get into that 2/3 full area. When that happens and I see 2/3 black, I know to not dump out my grey tank, instead I dump the black once the grey gets to its next 2/3+ mark so that I can use the grey to "clean" the Y connector and the flex hose of crap residue.


So I essentially never leave grey or black open. I just make it a point to watch the indicator and when the grey gets up there... I walk around back and pull the valve open for the 2 minutes or so that it takes to drain 25-ish gallons of grey water.


I will say that my flex hose does not smell crappy, I mean maybe if you stuck your face near it, it does... But in normal expected handling for connecting/disconnecting, the hose is for the most part clean and odor free.


I also do finish every full hook up camping session with 2 refills and flushes of the black tank and then 1 refill and flush of the grey tank to keep on top of tank maintenance. That adds around 30 minutes to our pack out procedure, but it leaves me feeling pretty good that I have really not allowed any solids to build up. If I am still seeing paper/solids going by.... I will add a 3rd or 4th black tank fill/flush until I no longer see indication of residual waste materials being removed. And then I finish with those grey tank flushes.


You could almost eat out of my flex hose.

[ependydad]

The only issue I've ever heard with leaving your gray tank open is that things (bugs, mostly) can come up from the sewer that can be unpleasant.

That said, 8 years of RVing (4.5 being fulltime), we almost always leave our gray open.

[fella10]

on a full hookup site, I leave the gray valve open full time, because I use the Sewer Solution and don't need the gray water to rinse the sewer hose after dumping the black tank, ... and if at a site without sewer, at the dump station I use the gray water and the hose setup below to help rinse the black tank quickly without hooking up and using the tank flush while others are waiting their turn, ...

[Herk7769]

I am a "Gray open - Black Closed" until the day before I need to dump; then I close the gray tank for showers and stuff.

After I dump the black and run the turbo flush till it runs clear, I close my end of dump mast valve and then pull the gray handle. That allows soapy water into the black tank.

Then I close the black tank and gray tank valves and open the end of mast valve, re-drain the black tank, close the black tank valve and open the gray tank for full draining.

I then run the turbo flush for about 30 seconds to put some water in the black tank to keep solids from sticking. I go inside and add 1 cap full of laundry detergent and 1 capful of Calgon Water softener.

[Larry-NC]

We have water and electricity on our site but no sewer. We use a 25 gallon tote pulled by a 1995 Club Car. We do not heat the trailer in the winter and the water is turned off. Thus we have two different practices: Summer and Winter.

In the Summer we leave both tank valves closed. When either gets the fourth LED lit, we dump black first into the tote. If it doesn't fill the tote, we top off with a little gray and take the first run. We use a different hose at the dump station; campground requirements require a solid connection there, so I have a hose with bayonet connector at one end (for the tote) and 4" IP or 3" slip fit (for the dump station). I dump and rinse that hose at the dump station, then go back and finish draining--the rest of the black if any, and as much gray as fits. Same routine for a third trip if both were really full.

In the winter we used bottled water. A little water from tooth brushing and hand-washing goes down the drains. We hook up the tote and leave the gray valve opened; the first winter we didn't and the pipes from gray tank to the valve froze and split. The dehumidifier sits in the shower and drains through the shower and gray tank into the tote.

In the winter only liquid body waste goes in the toilet. It's salty enough to lower the freezing point. We've never had a problem with leaving the black drain valve closed.

[Tundra 2014]

X2-Madatme

[Swampy]

Originally Posted by gastan

I know that, when hooked up in a site with a sewer connection, the black tank valve should not be left open - - - that the black tank should be left to fill at least 1/2 way before emptying in order to alleviate "build-up".

Is the same true for the gray water tank? Since it is mostly just soapy water (albeit dirty) and there is nothing to build-up, would leaving that valve open cause any problems? How do y'all set it up?

gastan;Ideally, you want to hold as much water in both tanks as possible prior to dumping. Leaving the grey water open doesn't harm anything, BUT when leaving the GT valve open, your rig may become the sewer vent for the park's sewer system when other campers dump plus you can get nasty 4 legged critters inside the tank from the park's sewer system. A good friend had this horrible smell overcome his TT and I helped him track it down to the GT valve being left open when I witnessed water gurgling in the kitchen sink drain with no water running in the rig, then came the horrible smell. We evacuated and the first thing I did was go to his dump valves and close the grey valve. I removed the other end of his dump hose from the CG sewer receptacle and there was a huge rush of major "el stinky" air pressure coming out. He kept the GT valve closed until his GT was full, then dumped and all was well. He and his DW were thankful that the issue had been resolved for the rest of the camping trip and I am very sure she will not let him keep it open again when they camp again. Good Camping ..... Swampy

[Reverse_snowbird]

Swampy;2253478]BUT when leaving the GT valve open, your rig may become the sewer vent for the park's sewer system when other campers dump plus you can get nasty 4 legged critters inside the tank from the park's sewer system.

^^^ This is why we keep our grey water valve closed until it need to be dumped.

[ncebeemer]

Both valves closed. Grey is emptied as needed, but held just before leaving to flush after black tank evacuation.

[gastan]

Thanks for all the responses. It's interesting to see how everyone handles it. I knew to have gray water to dump last to clean the hose (and I rinse it with clean water, too, if the dump station has it). I never thought of critters and smells coming in thru an open valve, though. And that's ironic, too, because we did have a small sewer rat get into our house once thru the toilet. We now keep the seats closed at all times and at night I won't use the toilet without first turning on the light so I can see what's what when I open it up.

[awellis3]

Originally Posted by gastan

... it is mostly just soapy water (albeit dirty) and there is nothing to build-up, …

Food particles will and do build up. And they can stank up the trailer.

[emm-dee]

If I’m in a full hookup site I don’t even get the slinky out until it’s time to dump. Grey tank usually needs it after five days but black tank is good for eight days or more.

[jimmoore13]

Grey water contains a surprising amount of particulate matter, from coffee grounds to bits of fried egg. It settles. Dumping a grey tank all at once will carry away most of this crud. Allowing the tank to remain dry by leaving the valve open will allow the particulates to collect on the bottom of the tank and slowly build up in the bottom of the tank as they glue themselves to the bottom of the tank in successive layers. This is a recipe for problems and stench.

Always keep both black and grey tanks closed until they have accumulated considerable amounts of effluent, then dump at full flow rate. If you happen to be at a full-hookups site, chase the dump with flushes and by running water through the greywater system to help flush out the tanks. Then close up and collect again.

P.S. I've boondocked exclusively for many years. My old rig was a PUP with a 12 gallon grey tank. It required dumping almost daily. We are in wilderness sites, so we use the "water the trees" method of getting rid of grey water. Our grey water was ONLY hand washing and dishwashing, but I assure you it had particulates, and it didn't smell particularly good. It was in no way hazardous, but it wasn't pleasant either. Keep your grey tank healthy and clean with vigorous, nearly-full dumps, or you'll regret it.

[Larry0071]

Originally Posted by jimmoore13

Grey water contains a surprising amount of particulate matter, from coffee grounds to bits of fried egg. It settles. Dumping a grey tank all at once will carry away most of this crud. Allowing the tank to remain dry by leaving the valve open will allow the particulates to collect on the bottom of the tank and slowly build up in the bottom of the tank as they glue themselves to the bottom of the tank in successive layers. This is a recipe for problems and stench.



Always keep both black and grey tanks closed until they have accumulated considerable amounts of effluent, then dump at full flow rate. If you happen to be at a full-hookups site, chase the dump with flushes and by running water through the greywater system to help flush out the tanks. Then close up and collect again.



P.S. I've boondocked exclusively for many years. My old rig was a PUP with a 12 gallon grey tank. It required dumping almost daily. We are in wilderness sites, so we use the "water the trees" method of getting rid of grey water. Our grey water was ONLY hand washing and dishwashing, but I assure you it had particulates, and it didn't smell particularly good. It was in no way hazardous, but it wasn't pleasant either. Keep your grey tank healthy and clean with vigorous, nearly-full dumps, or you'll regret it.

If you've ever accidentally stored grey water for a couple weeks in the summer and then dump it in a fashion that you can smell it.... It smells remarkably similar to your black water. The bacterial and algae growth is horrific and deadly. Grey water converts to black water with time and temperature.

I never leave grey tank open. Always fully flush out after a camping session to minimize any residual sediment and odors.

[Chuck_S]

If your camper is plumbed -- and maintained -- properly you can't get grey water stink inside. There should be P-traps in the sinks. (Toilet is different as it's a direct drop from bowl to tank.)

https://www.youtube.com/watch?v=zGofkKOP2SU

-- Chuck

[A32Deuce]

That works as long as you don't move your RV. Going down our wonderfully smooth highways does not empty the P traps, NOT! That's when you get smell!