Black water flush

[Waltdrechsler]

This is the first rv with a black water flush. Wondering if I put a Y with shut off valves from the water supply and run one hose to the city water input and the other to the flush input if there is a chance of black water getting into my fresh water side. The city water has a check valve but the flush fill does not.

Thanks in advance.

[Marcm157]

You will get mixed responses here but I run the Y as you describe. I have the y marked so the black hose always goes to the same side. There is a vacuum breaker somewhere in your black tank flush line that prevents back flow. They are very prone to failure though.

I removed mine and and the same time replaced the black tank flush Inlet with a city water one with a check valve which I feel is much more reliable.

[ARoamer]

I also use a Y with built in shutoff valves when at a site long term. I also use a quick connect on the flush hose connector at the panel. Shut the Y valve and pop the QC hose off when done.

[TaftCoach]

Yikes, I've been doing that without giving it a second thought. I always spray my connections with bleach when connecting and disconnecting. I will order a check valve today before my wife thinks of it.

[Waltdrechsler]

Originally Posted by Marcm157

You will get mixed responses here but I run the Y as you describe. I have the y marked so the black hose always goes to the same side. There is a vacuum breaker somewhere in your black tank flush line that prevents back flow. They are very prone to failure though.

I removed mine and and the same time replaced the black tank flush Inlet with a city water one with a check valve which I feel is much more reliable.

This is a great idea. I’ll follow your example

[Waltdrechsler]

Thanks, that is a great idea. I will follow your example

[Waltdrechsler]

I won’t tell….. Honestly you’re probably fine.

[LuckyDuck]

Similar to the others, I disinfect the hose bib when we set up and attach my “Y” with shutoffs. I use a black Zero G for the back-flush with a backflow preventer at the end between it the Y connection. I don’t leave it attached all the time but it has a quick connect for when I’m ready to back-flush the tank, or use it to hose off dirty gear. It’s isolated from the FW side.

[Marine71-76]

We also have a Y at the water source. Also have a "gray" hose that is specifically used for the black water tank flush. When I flush, turn off the water to main unit and turn on the water to flush. When setting up or breaking down, wipe down the connection for the hoses, the Y and the water source.

[Jim Smyth]

I used to use a Y with indivual shut offs till a camper friend told me his horror story. Seems all the water hookups were in a small area. Someone accidentally turned his black tank flush line on thinking it was theres. It was on for hours while the person was gone. So needless to say it came out and filled his camper up with black tank water. Underbelly and all insulation needed to be ripped out and replaced but it still smelled. So they traded the camper away.



Another horror story to a Park model trailer where there water was turned on accidentally during construction and filled the trailer up. Morel of the story is anything that can go wrong will go wrong. I only use 1 hose and just switch it back and forth. Theres a check valve in the black line (mine failed once and you get a water fall over the left wheel well) so nothing can come back the other way. For me I keep it simple.

[Waltdrechsler]

Wow, that is something to consider for sure! I probably won’t sleep tonight after that story!

[LuckyDuck]

Originally Posted by Jim Smyth

I used to use a Y with indivual shut offs till a camper friend told me his horror story. Seems all the water hookups were in a small area. Someone accidentally turned his black tank flush line on thinking it was theres. It was on for hours while the person was gone. So needless to say it came out and filled his camper up with black tank water. Underbelly and all insulation needed to be ripped out and replaced but it still smelled. So they traded the camper away.



Another horror story to a Park model trailer where there water was turned on accidentally during construction and filled the trailer up. Morel of the story is anything that can go wrong will go wrong. I only use 1 hose and just switch it back and forth. Theres a check valve in the black line (mine failed once and you get a water fall over the left wheel well) so nothing can come back the other way. For me I keep it simple.

As I mentioned, I don’t hook up the black tank flush hose until I’m ready to back-flush. Takes two seconds with quick connect. It doesn’t negate using the “Y” connector. Personally, I would never use one hose for my FW connection AND my black tank flush. Not worth the risk, check valve or not.

[Jerry713]

I have also removed the factory vacuum breaker from my black flush line. I do use a simple backflow preventer on the outside of the camper between the hose and the connection on the camper. To make sure there is no cross contamination.

https://smile.amazon.com/dp/B0049PLE...t_details&th=1

[Marcm157]

Originally Posted by Jim Smyth

I used to use a Y with indivual shut offs till a camper friend told me his horror story. Seems all the water hookups were in a small area. Someone accidentally turned his black tank flush line on thinking it was theres. It was on for hours while the person was gone. So needless to say it came out and filled his camper up with black tank water. Underbelly and all insulation needed to be ripped out and replaced but it still smelled. So they traded the camper away.

This is exactly why I never hook up my flush hose until I am ready drain and flush the tank!

[ARoamer]

Don't set yourself up for a potential huge mess. Quick connect at black rinse, Y with shut offs, everything is in reach. Access door is locked when done.

[Marine71-76]

Originally Posted by Jim Smyth

I used to use a Y with indivual shut offs till a camper friend told me his horror story. Seems all the water hookups were in a small area. Someone accidentally turned his black tank flush line on thinking it was theres. It was on for hours while the person was gone. So needless to say it came out and filled his camper up with black tank water. Underbelly and all insulation needed to be ripped out and replaced but it still smelled. So they traded the camper away. [snip]

And that is why I only connect the gray hose when I am ready to dump and then disconnect it once I am done. Never leave it connected to the trailer just for the above reason.

[Waltdrechsler]

That looks like a nice clean set up. Thank you

[thepaulsri]

My outside faucet connector (ie outside shower) with standard hose connector, is part of my Nautilus panel and I connect the output from the outside faucet to the black water flush inlet. Then I can turn on the water faucet, including hot water, to run into the black water flush. I think this keeps my black water flush pretty isolated from my fresh water.

[Hollander Mutthaulers]

I use quick connects on both hoses and try to remember to spray the faucet and handles on the bib with lysol before attaching them.
White fresh water has a reducer, filter and Y attached. Y is for any auxiliary non-black tank rinse hose.
Green hose for black tank rinse only and only have it attached during rinsing.
Quick connects make it super easy to change hoses and the piece of mind and aesthetics is worth it to me.
Installing a city water fill inlet with a back flow preventer for the black tank flush sounds like a super idea.

[billcf7]

Originally Posted by thepaulsri

My outside faucet connector (ie outside shower) with standard hose connector, is part of my Nautilus panel and I connect the output from the outside faucet to the black water flush inlet. Then I can turn on the water faucet, including hot water, to run into the black water flush. I think this keeps my black water flush pretty isolated from my fresh water.

Your outside faucet connected to your black flush is also a bad idea if your black flow preventer were ever to fail. I never let any black come in contact with anything fresh