What to do w/gray water on full hookup

[Larry-NC]

Originally Posted by bubbles

If there's wind blowing up the hose into the tank then the sewer connection is not done properly. The hookup is supposed to be a sealed connection.

Huh? Can you explain clearly exactly how this is done?

[V6TOY4X]

Originally Posted by BriaBeck

We just treat a FHU site as a regular site with a dump station... we really don't do anything differently, except take a little longer showers and rinse the dishes a little better. We keep all the valves closed, and if a tank gets full, we just drain it.

THIS!

[Tom48]

Originally Posted by cboss

Exactly. And let the black tank fill up a little also, it helps to break down the sludge. Always dump the black first, rinse out with the gray.

Ditto. AND NEVER leaves the black valve open, except, of course while actually dumping.

[Scrapper]

Originally Posted by bubbles

If there's wind blowing up the hose into the tank then the sewer connection is not done properly. The hookup is supposed to be a sealed connection.



The black tank continuously expels gas out a vent stack.

Originally Posted by Larry-NC

Huh? Can you explain clearly exactly how this is done?

I don't understand how bubbles thinks this works. You cannot have a closed system in a sewer system. Whenever you dump into the system air/sewer gasses needs to go somewhere when it's displaced.

All the full hookup sites at the campground needs a vent. If the only venting is done through your roof vent it will take a while for the contents in your tank to run out. The underground tank will accept just so much sewage before the pressure builds up enough to stop the in-flow, that pressure pushes back into your holding tanks then through the roof vent. Once the pressure inside both tanks are equalized the whole process starts over until the holding tanks are empty. Try closing off any and all vents to your holding tank and see how long it takes to empty. Even the sewer system at your home needs a vent at both ends.

When something goes in, then something must go out, if something goes out, then something must go in. It doesn't make a difference if it's your holding tank or the sewer tank in the ground.

The same if your fresh water tanks vent is plugged when you fill it with a pressurized source, the tank will expand, not because you over filled it, but because the displaced air cannot come out.

If you ever fill a 5 gallon jug with water, turn it upside down then remove the cap you will see what I mean. There will not be a steady out-flow of water.

[bubbles]

Originally Posted by Scrapper

I don't understand how bubbles thinks this works. You cannot have a closed system in a sewer system. Whenever you dump into the system air/sewer gasses needs to go somewhere when it's displaced

I did not say a "closed system" I said a "sealed system" from sewer connection to RV connection and that was in answer to the premise that a wind could blow the sewer gasses back up the sewer hose out the roof top vent. I believe most if not all commercial campgrounds with FHU's require a sealed sewer connection with either a sewer connected hose end or the use of a donut or something to accomplish it that would prevent any wind input to the sewer hose. I also add that if someone uses the sewer connection without some way of sealing it that individual is just disrespectful to fellow campers.

[dwilli1]

Thanks everyone for your replies...it's as I thought. Don't dump til you need to, then black first, flush w/ the gray. Thanks again!!

[Philandterry]

Originally Posted by dwilli1

Hi All. My first "full hookup" campsite and I'm wondering what to do w/ the gray water tank. I'm hooked up and was running gray water w/ the gate valve open to go directly into the septic but thought I should close it a couple days before we leave to have something to flush the hose from dumping the black water. What does anybody do here? I know to leave the black tank closed until we're ready to dump....should I just use the "flush" valve to help clean out the hose? or should I use some gray water to do that? Help is appreciated. Thanks!

You are doing it effectively, Dirtiest to cleanest, but If you ever get sewer fly infestation, you will never leave your grey tank valve open again. They come thru the sewer hose and then never want to leave.

[NMWildcat]

Originally Posted by Philandterry

You are doing it effectively, Dirtiest to cleanest, but If you ever get sewer fly infestation, you will never leave your grey tank valve open again. They come thru the sewer hose and then never want to leave.

If you have sewer flies/gnats, they are easy to get rid of. Fill your tanks with water, add Clorox, let it sit overnight or so. Gone, eggs also dead.
We usually leave tank valves closed, but sometimes I'm just too lazy to keep going out and draining the gray at inopportune times, especially if we have company and are producing a lot of gray water. So I will leave the gray open.
If you are concerned about sewer gnats or gases coming up your hose, just create a p-trap in the hose itself, deep enough to keep the entire p-trap portion filled with water. Simple. Easy.

[HappyCamper1962]

Originally Posted by BriaBeck

We just treat a FHU site as a regular site with a dump station... we really don't do anything differently, except take a little longer showers and rinse the dishes a little better. We keep all the valves closed, and if a tank gets full, we just drain it.

x2 this is exactly what we do. Love those longer showers

[NXR]

Originally Posted by NMWildcat

If you have sewer flies/gnats, they are easy to get rid of. Fill your tanks with water, add Clorox, let it sit overnight or so. Gone, eggs also dead.

...

If you are concerned about sewer gnats or gases coming up your hose, just create a p-trap in the hose itself, deep enough to keep the entire p-trap portion filled with water. Simple. Easy.

If it were only that simple. When we had them at work the bathrooms were infested with the little buggers. All of those sinks have P-traps and are used every day of the week. The plumbing guys dumped all kinds of stuff into the drains but that cannot kill the ones flying around the room for weeks.

https://www.orkin.com/flies/drain-fly

How Do I Get Rid of Drain Flies?
Generally, the best control for these flies is to remove the breeding site, which is the organic material that collected in the drain. The site must be located and cleaned. Drain cleaner will not fix the situation.

Once the material is removed (along with the larvae) the problem is solved, except for the adult flies. They will live about 20 days, but will have no place to lay eggs to continue their life cycles.

Ray

[grumpyoldman]

I must be in the minority, because I leave my gray tank valves open at my seasonal site. (Take long showers, wash dishes like at home and have a clothes washer) When I dump the black tank I flush all three of my tanks, one at a time, with a water hose connected to an add on dump valve on the sewer outlet. Open one gray tank valve, close the add on dump valve, open the water hose on the upstream side of the add on dump valve. I let the water flow back into the tank for about 10 minutes, shut off the water hose then open the add on dump valve. I watch the clear section of this add on valve to ensure the water is clear.
I do have a built in black tank flush connection that I use, but I also use the water hose flush via the add on dump valve. I do get additional gunk out after using the built in black tank flusher.

[NMWildcat]

Originally Posted by NXR

If it were only that simple. When we had them at work the bathrooms were infested with the little buggers. All of those sinks have P-traps and are used every day of the week. The plumbing guys dumped all kinds of stuff into the drains but that cannot kill the ones flying around the room for weeks.

https://www.orkin.com/flies/drain-fly

How Do I Get Rid of Drain Flies?
Generally, the best control for these flies is to remove the breeding site, which is the organic material that collected in the drain. The site must be located and cleaned. Drain cleaner will not fix the situation.

Once the material is removed (along with the larvae) the problem is solved, except for the adult flies. They will live about 20 days, but will have no place to lay eggs to continue their life cycles.

Ray

Much different situation than an RV.........

[Bhrava]

Originally Posted by NXR

If it were only that simple. When we had them at work the bathrooms were infested with the little buggers. All of those sinks have P-traps and are used every day of the week. The plumbing guys dumped all kinds of stuff into the drains but that cannot kill the ones flying around the room for weeks.

https://www.orkin.com/flies/drain-fly

How Do I Get Rid of Drain Flies?
Generally, the best control for these flies is to remove the breeding site, which is the organic material that collected in the drain. The site must be located and cleaned. Drain cleaner will not fix the situation.

Once the material is removed (along with the larvae) the problem is solved, except for the adult flies. They will live about 20 days, but will have no place to lay eggs to continue their life cycles.

Ray

So thats what these little buggers are in my basement. They drive me nuts and I have not found where they are coming from either. Annoying buggers, fly right at my face. I must kill a dozen or more a day. I checked all my sump pits, nothing but clear water, and the one in my workshop where my work office is located is flushed at last twice a day from the washing machine, ac condensation, and laundry sink. I will have to dig deeper now to find out where they are breeding. Probably my son's room, I sure hope my room wasn't like that when I was a teen!

[reevesfamily]

Originally Posted by eye95

We keep both valves closed. If the gray tank fills, we partially empty it. We want as much gray water as possible to flush the sewer hose after emptying the black. We haven’t completely filled the black yet, so there hasn’t been a need yet to even partially dump it before the end of a trip.

On another forum, my wife read a post from a person who reported a sewer smell in his RV. He thought this shouldn’t happen because he left his gray valve open. Several people alerted him that this could actually contribute to the sewer smell if (for some reason) one of his traps was not blocking sewer gas.

My advice: Keep you valves shut. Dump only at the end of your trip or if a tank becomes full. If you either of your tanks becomes full, only partially dump it.

Spot on. Both gate valves closed until dumping tanks. We typically dump the gray tank several times on a trip, but the black once when we get ready to leave. Try to make sure to have full gray to flush the hose after dumping black tank, but with my tank flush and my process of cleaning it I end up with clear water out of the black tank anyway. Leaving gate valves open is just not a good idea.

[OLEJOE]

Originally Posted by NMWildcat

If you have sewer flies/gnats, they are easy to get rid of. Fill your tanks with water, add Clorox, let it sit overnight or so. Gone, eggs also dead.
We usually leave tank valves closed, but sometimes I'm just too lazy to keep going out and draining the gray at inopportune times, especially if we have company and are producing a lot of gray water. So I will leave the gray open.
If you are concerned about sewer gnats or gases coming up your hose, just create a p-trap in the hose itself, deep enough to keep the entire p-trap portion filled with water. Simple. Easy.

You could draw a picture and they still wouldn’t get it. I leave our grey valve open also along with the p-trap in the discharge hose. No smell or bugs.

[bowebow]

first I find out how many days our family takes to fill gray tank. let's say 5 days estimate. black tank usually takes 3 weeks. encourage them not to put to much paper in toilet. use wastebasket for cleaner paper. when a smell occurs or shower pan get wet or say 4 days. dump black, raise hose to floor height open gray, fill a black, close gray , dump black, repete, then dump gray completely. empty hose close valves. when prepping to leave dump day before so there is slosh to clean tanks or dump at leaving and add a little clean slosh water with chemical additive.

[Skidooman]

No one goes #2 in our camper. If you dump in the camper you dump the camper. So far in 7 years no one ever has. So when at a full hook up site we leave the gray and black valves open

[NMWildcat]

Originally Posted by Skidooman

No one goes #2 in our camper. If you dump in the camper you dump the camper. So far in 7 years no one ever has. So when at a full hook up site we leave the gray and black valves open

I do believe that is a little more extreme than most of us will consider

[Moore Travels]

Originally Posted by BriaBeck

We just treat a FHU site as a regular site with a dump station... we really don't do anything differently, except take a little longer showers and rinse the dishes a little better. We keep all the valves closed, and if a tank gets full, we just drain it.

Same here...and I use the black tank flush when I can for added cleanliness!

[Midwest Ed]

Originally Posted by Witch Doctor

I have learned to keep my tank valves closed even with full hook ups , you don’t want what ever is in the CG tank coming back into your RV. If you need to dump just dump. But leave all the tank closed.

My mind immediately went to the sewer/compactor scene from Star Wars...some wicked stuff living in there.