Black tank flush back flow valve

[JPSCOTT123]

The black tank flush backflow/vacuum valve on my 2020 Cardinal is stuck and won’t let water through. Where can I by a replacement or should I just remove it?

[Herk7769]

The in-tank flush nozzle could be plugged or the vacuum break could be stuck.

The vacuum break is an easy fix because it is inside your camper somewhere near the outside hose connection. It can just be bypassed to check it; if bad, you must replace it to prevent black water from siphoning overboard when traveling.

https://www.amazon.com/Camco-Assembl...s%2C147&sr=8-1


The Nozzle is harder because you will first need to get access to the black tank's fittings. Normally, this will involve dropping the belly coverings to find out where they are located. (Don't pick a windy day for this)

It is easier to just drill a new hole in the black tank and install a new nozzle; then reroute the existing tubing to the new nozzle. Trying to remove the bad one and then fit the new nozzle in the old holes will leave you with potential leak sites.

https://www.amazon.com/Camco-40126-T...208693&sr=8-28

[bubbles]

Originally Posted by Herk7769

The in-tank flush nozzle could be plugged or the vacuum break could be stuck.

The vacuum break is an easy fix because it is inside your camper somewhere near the outside hose connection. It can just be bypassed to check it; if bad, you must replace it to prevent black water from siphoning overboard when traveling.

https://www.amazon.com/Camco-Assembl...s%2C147&sr=8-1


The Nozzle is harder because you will first need to get access to the black tank's fittings. Normally, this will involve dropping the belly coverings to find out where they are located. (Don't pick a windy day for this)

It is easier to just drill a new hole in the black tank and install a new nozzle; then reroute the existing tubing to the new nozzle. Trying to remove the bad one and then fit the new nozzle in the old holes will leave you with potential leak sites.

https://www.amazon.com/Camco-40126-T...208693&sr=8-28

What?

[babock]

I replaced my backflow valve with a brass elbow. You can always use an anti siphon device on your flush hose if you desire.

[KyDan]

I discovered the same issue on my trailer just last week. It's not completely blocked but very low flow. I donno how the nozzle could have gotten blocked but stuck back flow or a kinked water line came to mind. I'll probably try removing the outside flange/hose connection and see what I can see. Maybe there's enough slack to pull it out a few inches and have a look.

[nomad297]

Originally Posted by babock

I replaced my backflow valve with a brass elbow. You can always use an anti siphon device on your flush hose if you desire.

Doing what you did is irresponsible and unsafe, and it puts everybody connected to the same water system as you at risk of illness or death — all because you want to save a buck.

You obviously don’t understand the importance and purpose of this particular type of backflow device — most people don’t. Different cross connection situations require different levels of protection, and you can’t just “use [any old] anti siphon device on your flush hose if you desire” to create the same level of protection required to keep fecal matter from entering a potable water system.

I just can’t understand why people don’t take this kind of thing seriously and why they think they have better solutions than those designed for a particular situation and mandated by law/code. I have been in this business my entire adult life and I have seen some pretty bad things happen after people have decided to do away with or substitute a different type of backflow preventer for the type that should have been used.

For the sake of saving me from developing sores on my fingertips, I will just refer you to this thread I started here a year or so ago:

https://www.forestriverforums.com/fo...ns-191907.html

Bruce

[babock]

Originally Posted by nomad297

Doing what you did is irresponsible and unsafe, and it puts everybody connected to the same water system as you at risk of illness or death — all because you want to save a buck.

You obviously don’t understand the importance and purpose of this particular type of backflow device — most people don’t. Different cross connection situations require different levels of protection, and you can’t just “use [any old] anti siphon device on your flush hose if you desire” to create the same level of protection required to keep fecal matter from entering a potable water system.

I just can’t understand why people don’t take this kind of thing seriously and why they think they have better solutions than those designed for a particular situation and mandated by law/code. I have been in this business my entire adult life and I have seen some pretty bad things happen after people have decided to do away with or substitute a different type of backflow preventer for the type that should have been used.

For the sake of saving me from developing sores on my fingertips, I will just refer you to this thread I started here a year or so ago:

https://www.forestriverforums.com/fo...ns-191907.html

Bruce

Blah Blah Blah Always somebody head explodes when I say this.

Its fine. 3 things would have to happen. I would just happen to be doing this at the time. The sprayer would have to be above the contents of the liquid in the tank(That would never happen). And the area would have to lose water pressure.....all at the same time.

I took the backflow preventor off the output of my garbage disposal too!!!!!

I know too many people that have soft floors because the back flow valve was leaking over a long period of time.

[JPSCOTT123]

Well, we left the RV park and drove to the next park. Tried it again and it works just fine! I think it was stuck in a closed position and bouncing along the road freed it up. If it happens again I'll replace it. Thanks to all for the comments.

[nomad297]

Originally Posted by babock

Blah Blah Blah Always somebody head explodes when I say this.

Its fine. 3 things would have to happen. I would just happen to be doing this at the time. The sprayer would have to be above the contents of the liquid in the tank(That would never happen). And the area would have to lose water pressure.....all at the same time.

I took the backflow preventor off the output of my garbage disposal too!!!!!

I know too many people that have soft floors because the back flow valve was leaking over a long period of time.

Whatever you do is up to you.

You may want to read your post over and think about how nothing that you wrote makes sense, then edit it again to show that you have a grasp on how backflow preventers work and what they do. I will give you a couple of hints to get you started:

1/ The sprayer would need to be submerged in the contents of the tank.
2/ Garbage disposals do not have backflow preventers — the output of the disposal dumps into the drain. Older installations of dishwashers (not disposals) may have an air gap that connects to an inlet on a disposal, but they aren’t required anymore due to check valves being installed on the pump outlet at the dishwasher and the discharge hose from the dishwasher is required to be routed to a position higher than the inlet on the disposal. Your bringing this into the conversation just goes to show that you don’t have an understanding of basic plumbing and backflow prevention.

You can go ahead and discount what I wrote in my previous post as “Blah Blah Blah” all you want, but you should not be on here telling people to do things that are harmful and deadly.

EDIT: I will not be responding to any further argumentative posts from you. I have made my point and I have provided you with some useful and informative links to help you and others understand the importance of these backflow preventers.

Bruce

[wmtire]

Originally Posted by JPSCOTT123

Well, we left the RV park and drove to the next park. Tried it again and it works just fine! I think it was stuck in a closed position and bouncing along the road freed it up. If it happens again I'll replace it. Thanks to all for the comments.

Great to hear. Some very useful ( and maybe not so) information has been provided that may help others. We are going to close this thread to look at some things for review.