Bathroom flooded thanks to lovely little one way valve

[Frznrth]

Hi
I have a two year old bullet. It has a black tank clean out option that seems like a great idea - used it last year and it worked great. This year when I used it, after our first trip, I ended up with a flooded bathroom. The lovely little "one way" valve under the bathroom sink was shooting water everywhere. My thought - what a dumb place to put a cheap little piece of crap valve. Either use a decent valve or put it someplace that won't flood the inside of the trailer when it does fail. Not impressed.

Anyone have the same problem? Are there better valves available? Is the valve there to prevent sewer smell from coming back up? - Do I need the valve? - How can I keep this from happening again?

Thanks for the vent.

[Ayotte]

I heard stories like yours so I completely removed the valve before it leaked and just connected the lines together. Works fine. I think the idea of the valve is to prevent back flow. But how could that happen when the inlet you hook onto is higher than the toilet and the tank is vented!

[hankpage]

Sorry to hear about your flood. If you do a forum search you will find MANY complaints about this check valve. Yes, it is cheaply made but it also needs to be winterized along with the rest of the plumbing in the trailer. When you do the search you will find what others have done to solve this common problem. Good luck and welcome to the forum, Hank

[JRTJH]

Originally Posted by Ayotte

I heard stories like yours so I completely removed the valve before it leaked and just connected the lines together. Works fine. I think the idea of the valve is to prevent back flow. But how could that happen when the inlet you hook onto is higher than the toilet and the tank is vented!

If you'll relate the possibility of backflow that is "higher than the toilet", just think of the way we used to siphon gas out of a tank. The hose was always "higher than the tank" when we had gas flow. The anti-siphon valve is not attached to the toilet, it's attached to the side of the black tank about 1/2 way up the side. If the tank is 3/4 full, the spray nozzle in the tank is submerged in black tank effluent and could siphon back up the hose. The black tank vent (on the roof) would help provide sufficient air to keep the "flow going" if it did occur.

The anit-siphon valve does prevent black tank contents from "siphoning" back up and out the black tank rinse connection. Is it likely to happen? Probably not, but it is possible. That's why the valve is there: To stop the flow of liquid "and gas" effluent back into the city water system.

There are brass anti-siphon valves available at Lowe's and HD that can replace the "cheap plastic valve" and provide much better protection against leakage under the sink.

If you do completely remove the valve, you might want to consider adding a "one way valve" or a "screw on anti-siphon valve" to the black tank coupler when you attach your water hose. That way, you eliminate the chances of siphoning black tank effluent back into your water hose and the city water system.

[Frznrth]

Thanks for the info. I will definitely look for a brass valve and will hope it doesn't happen again.

[Lee]

Hi,

After reading all of the horror stories concerning this valve, I want to replace it BEFORE it blows.

I have searched the HomeDepot and Amazon websites but am confused by all of the choices.

Can someone please suggest a brass constructed valve that will work as a replacement for the cheap plastic one?

Thanks,
Lee

[Javi]

Originally Posted by Lee

Hi,

After reading all of the horror stories concerning this valve, I want to replace it BEFORE it blows.

I have searched the HomeDepot and Amazon websites but am confused by all of the choices.

Can someone please suggest a brass constructed valve that will work as a replacement for the cheap plastic one?

Thanks,
Lee

I use this... http://www.homedepot.com/p/Homewerks...PZ4B/202369987 In Waco a city ordnance requires them on every hose connection.

[KJcachers]

My bullet did it too after the first winter. You really need to make sure you push antifreeze through the black tank flush connection to prevent it from freezing and breaking.

[JRTJH]

The antisiphon valve is prone to freeze damage. If you don't want to replace it with a brass valve (about $15) I'd urge you rather than try to winterize it, simply remove it, take it inside with your batteries and just reinstall it in the spring.

I can almost guarantee you that if you leave it in place, push a cup or so of RV antifreeze through the side connection, you will be ordering another $47 valve or going to HD or Lowe's in the spring. They are simply fragile and extremely sensitive to freezing.

Good Luck whatever you choose to do.

[LuvsPalmTrees]

We made it through one year without it freezing - but it got us this year. My DH realized he forgot to winterize it and first outing in the spring - it broke - bathroom was a mess.

[Miamogue]

J have a little different problem. Own a 2014 313RLI 5th wheel. Have been using the trailer on cross country for the past two months. Have used the black tank flush many times. Went to use it the other day and the system just pressurized and no water to tank. Removed and checked the vacuum vale and it was working. Put a 90 in the line and re-pressurized the line. No water to tank. Is there another valve in the system? What can I use to clean out line (liquid plumber)? Where dose the flush nozzle enter the tank (top or side)? Could use some help on this one.

[Lee]

Hum,...... I hope that the line has not seperated from the port where it enters the tank. Yer not leaving a puddle under the RV are you?

I know of no other valve in this line other than the stated back-flow one.

[dandjh1958]

I had learned from the wise folks on this forum to double check any and all connections I could reach the first time I turned city water on in my trailer. I also double check each connection every year just to make sure they are tight.
I also remove this and the toilet valve after I blow out the lines for winter. They are very prone to freezing but not if I remove them and plug the ends!!

So far, so good! I have learned so much from this forum and look forward to all the good information and humor yet to be had!

Happy camping!!!

[gearhead]

OK, I need some help here.
So the plastic anti-siphon valve is on the black tank flush line? Or, on the tank itself? Or both?
When it fails, how do you know? Do black tank contents leak out, or does the tank flushing line spray out under the floor when used?
I assume I have to cut out chloroplast when replacing it?

[JRTJH]

Originally Posted by gearhead

OK, I need some help here.
So the plastic anti-siphon valve is on the black tank flush line? Yes, it is usually located under the bathroom sink.

Or, on the tank itself? No, the only "flush component" located on the tank is the actual nozzle that sprays Or both?
When it fails, how do you know? The underside of the bathroom sink will start filling with water and if your DW happens to be inside, you'll hear the "shrilling scream" as she lets you know, "There's water everywhere!!!"

Do black tank contents leak out, NO or does the tank flushing line spray out under the floor when used? Possibly, if the 1/2" PEX line is also cracked or damagedI assume I have to cut out chloroplast when replacing it? No, I've not seen any RV with the anti-siphon valve inside the coroplast. As said, usually it's under the bathroom sink, but on some previous models, it was installed in the wall behind the shower. When there, there is an "access panel" somewhere... Often beside the entertainment center in the living room. Take off the panel and the valve is accessible.

Hope this makes sense to you.....

[gearhead]

So the flush line goes from outside the RV to up under the sink in the cabinet, or in the wall, and from there back down to the side of the black tank? I think I got it!
I'll go look for it, when the trailer gets out of the shop.

[Brantlaker]

What I would do is blow air through the system and loosen the line connection at the back flow valve to see if the line is blocked before the valve or after there may be a kink in the pex line look in the storage area under the sink or in the basement.

[Scalemaster]

Mine is located behind a panel on the wall above the toilet. Can't imagine the damage it would cause if it let go inside the wall. Will be removing it and adding the brass anti siphon at the connection point. Looks like 2 different line sizes. Possible 1/2 pex and 3/8 pex.

[gearhead]

So there we were on the shakedown cruise. I found myself on the throne contemplating life; open the door under the sink for the TP, hmmmm there is the blue line, and the red line going to the sink, then there are 2 white lines. What are they for?
Ding ding ding...THAT'S the anti-siphon line. Sure enough, I stood on my head looking upside down and there was something waaay up under the sink the white lines are connected to.
Now I get it!
Thanks to all!

[JRTJH]

I'm sitting here, reading this, shaking my head, smiling and thinking outloud, "Life is good, gearhead gets it"