Black tank flush

[14george]

Do not know if I'm in the right section but flushed tank out when we left campground had to use the bathroom on way home yesterday when out to drain tank and flush it out no water would flow to flush tank out. Took out check valve going to replace it with a nipple and use a check valve on hose.

[Face Down]

I have not had many problems with my new Carbon, but this is one that I have had. I have two black tank flushes systems (floor-plan has a bath and 1/2) and neither of them were working. The main bathroom would leak through the vent and the rear bath was same as you, no water at all through the nozzle. After researching I came to the conclusion to just delete both vacuum breakers. I cannot see a scenario where I could siphon anything from the black tank out through the piping of this system anyway. I used just a nipple and an elbow, cost a whooping $1.08 each to replace.

https://dl.dropboxusercontent.com/u/16283056/722015231732.jpg

[14george]

I have not had many problems with my new Carbon, but this is one that I have had. I have two black tank flushes systems (floor-plan has a bath and 1/2) and neither of them were working. The main bathroom would leak through the vent and the rear bath was same as you, no water at all through the nozzle. After researching I came to the conclusion to just delete both vacuum breakers. I cannot see a scenario where I could siphon anything from the black tank out through the piping of this system anyway. I used just a nipple and an elbow, cost a whooping $1.08 each to replace.

https://dl.dropboxusercontent.com/u/16283056/722015231732.jpg

That's what I'm going to do with mine thank you that is the same valve I have

[Face Down]

That's what I'm going to do with mine thank you that is the same valve I have

Much happier. When I did a leak test you can really hear the jet of water hitting the inside of the tank now. No more restriction and it is going to get the tank cleaner, faster now. ;)

[Ittle Dew Too]

I would love to do mine, but I don't know where it is located in the 2014 28RBS.

[SteveC7010]

I would love to do mine, but I don't know where it is located in the 2014 28RBS.
If you'd do a little searching back through the posts here, you will find dozens of posts and threads about the location of the black tank flush vacuum breaker.

In many of the trailers, it is up high inside the cabinet for the bathroom sink. You can trace the piping from the the blank tank flush connection and see where it goes up into the floor of the trailer. The vacuum breaker will be about 3 feet above that point.

Here's a diagram of a typical black tank flush system. It's pretty simple so you should not have much trouble locating the vacuum breaker.
http://beamalarm.com/image/Plumbing/no-fuss-flush.jpg

[14george]

If you'd do a little searching back through the posts here, you will find dozens of posts and threads about the location of the black tank flush vacuum breaker.

In many of the trailers, it is up high inside the cabinet for the bathroom sink. You can trace the piping from the the blank tank flush connection and see where it goes up into the floor of the trailer. The vacuum breaker will be about 3 feet above that point.

Here's a diagram of a typical black tank flush system. It's pretty simple so you should not have much trouble locating the vacuum breaker.
http://beamalarm.com/image/Plumbing/no-fuss-flush.jpg

I located mine going to like face down did with his(tx)

[ncrzrbk]

I want to do this as well. What size fittings are those?


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[SteveC7010]

I want to do this as well. What size fittings are those?


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They look to be 1/2" NPT, but the only way to be sure is to pull yours out and check it. While many of them are 1/2" NPT, Murphy's Law may still apply. RV manufacturers are notorious for using whatever they can get this week from their suppliers.

[14george]

I want to do this as well. What size fittings are those?


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Mine are 1/2 inch

[ncrzrbk]

Replaced the back flow with a brass fitting and nipple this afternoon. Seems to work much better getting water to the black tank sprayer!! Thanks for the info everyone.


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[JRTJH]

Be sure to use a pressure regulator with your black tank flush. The "weakest link" for you used to be the anti-siphon valve, now it's the nozzle INSIDE your black tank. Too much pressure and you can destroy it, then all you'll have is a "hole that spills water into your black tank. The repair for a "blown nozzle" isn't a pleasant task !!! :)

[ncrzrbk]

Thanks I will add the 40 psi regulator to the black tank rinse side


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[14george]

Put the elbow in like face down still no water yo nozzle got water to the elbow thanking the nozzle bad

[Ittle Dew Too]

How can I trace the line with the inlet ( where you attach the hose ) is a fitting in my docking station a few feet up the exterior wall in the front drivers side wall in front of the slide out and the black tank is in the back of the trailer and I have a completely inclosed underbelly? I have no idea where the vac breaker might be.

[14george]

How can I trace the line with the inlet ( where you attach the hose ) is a fitting in my docking station a few feet up the exterior wall in the front drivers side wall in front of the slide out and the black tank is in the back of the trailer and I have a completely inclosed underbelly? I have no idea where the vac breaker might be.
Look under bathroom sink if it is there you will see 3 white water lines and 1 red

[Face Down]

How can I trace the line with the inlet ( where you attach the hose ) is a fitting in my docking station a few feet up the exterior wall in the front drivers side wall in front of the slide out and the black tank is in the back of the trailer and I have a completely inclosed underbelly? I have no idea where the vac breaker might be.

The vacuum breakers will be installed a couple of feet above the tank itself and as other have mention usually under the bathroom sink. While researching this last week, some older models have the breaker installed in the wall, I am glad I did not have that configuration!! Even though I was 99% sure of what I was doing, I used a shot of compressed air after the breaker was off to verify I was removing the correct piece.

[Face Down]

Put the elbow in like face down still no water yo nozzle got water to the elbow thanking the nozzle bad

Bummer....I might let the dealer handle that one!

[14george]

Bummer....I might let the dealer handle that one!

Take it to dealer sat(tx) for your help

[SchafferFamily]

So, newbie question here. What does this valve do in the first place? By removing it and making a regular elbow there, what feature are we taking away or risk are we taking on? seems to be a common issue that is posted in the searches. Even replacing it with a brass one by some members.

I'm picking up our new Passport this saturday, and I"m going to see if we have a tank flush system or not, but if I do I don't want to risk having a leak inside the new camper. I've got plenty of PEX supplies, since we remodeled our house and I"m handy, so I'm not worried about doing it myself.

[14george]

So, newbie question here. What does this valve do in the first place? By removing it and making a regular elbow there, what feature are we taking away or risk are we taking on? seems to be a common issue that is posted in the searches. Even replacing it with a brass one by some members.

I'm picking up our new Passport this saturday, and I"m going to see if we have a tank flush system or not, but if I do I don't want to risk having a leak inside the new camper. I've got plenty of PEX supplies, since we remodeled our house and I"m handy, so I'm not worried about doing it myself.valve to prevent back flow. Mine located under bathroom sink Face down has a picture of it in this post

[SchafferFamily]

Right,... so if we remove it, and if our water valve is near the same elevation as our hookup for the hose, I guess potentially there could be a chance of this line having some black water in it, at least up the one vertical side under the sink?

I guess it is more important to maintain the high elevation of the elbow to keep that point higher than the black water tank entirely.

(Looking at diagram in Post #6)

[Face Down]

From what I understand it is installed to keep a siphon situation from happening and sending contamination back into the water system ....but it seems to me this is very unlikely. For this to happen...


Your black tank would need to be full up to where the spray nozzle is located.
With the tank full, a hose hooked up to the Flush System
All valves on the water system open
Water system loses all pressure
Then and only then, could a siphon happen.


Since I only use the spray system once the tank is empty and open...it could could not happen with what my procedure is for flushing the tanks.

[SteveC7010]

Right,... so if we remove it, and if our water valve is near the same elevation as our hookup for the hose, I guess potentially there could be a chance of this line having some black water in it, at least up the one vertical side under the sink?

I guess it is more important to maintain the high elevation of the elbow to keep that point higher than the black water tank entirely.

(Looking at diagram in Post #6)
The height alone is not enough. Remember this is an anti-siphon device. Under the right conditions, the nasty stuff can still back feed through this line without the vacuum breaker in place.

You're better off to see if you have a problem first. If you decide to remove the vacuum breaker, use an anti-siphon hose bib on your garden hose where you attach it to the flush inlet. I got several of them with various aftermarket RV accessories for flushing waste lines. If you don't have one, they're cheap and readily available at home improvement centers and hardware stores: http://www.homedepot.com/p/Orbit-Hose-Bib-Anti-Siphon-Valve-67750/203720437

More info: If your vacuum breaker is brass, the chances of it failing are much slimmer that with the plastic ones. That would definitely fall into the "if it's not broke, don't fix it" category.

Folks forget to winterize the the black tank flush which could leave water in the vacuum breaker. When it freezes, it may break the plastic ones. Brass, not so much. I have an air to garden hose fitting and use it to blow out the black tank flush in the fall. It's not easy to pump the pink stuff up there, but a blast of air is sufficient to protect it over the winter.

http://www.keystoneforums.com/attachments/photobucket/img_181280_0_7cd553847f57aaa11838ff5c61dbaa1c.gif

[SchafferFamily]

Thanks Steve. I have one of those Air connection fittings and a regulator from winterizing our popup (that didn't have a black tank, only sink and grey water).

Also, thanks everyone for the clarifications,... trying to be patient and waiting for Saturday. My wife and I are excited to move up to the new camper.

[14george]

Take it to dealer sat(tx) for your help

Took it to dealer worked there?