What Is This? Black Water Tank Flush???

74Beeper

Member
I took possession of my 2009 Razor 3612TS last weekend. I've been going through it and getting familiar with it. This is my first camper and I'm still learning but what is the hose connection on the lower left? (See picture... it uploaded sideways)
I know the upper right hose connection is city water. I hooked it to city water and it flows out of the fuctets. But when I hook to the lower left hose connection, nothing happens. The water just deadheads. I called Heartlannd and they weren't much help. They said it could be a black tank flush but really not sure because they don't keep info on anything this old. (Really?)

I removed the inner panel and followed the line. It's red, goes across to the right side and turns to the rear and that's where I lose it.

If this is a black tank flush, is there another valve that's needs opening that I'm missing? Any help would be greatly appreciated
. IMG_0071.jpg
 

danemayer

Well-known member
Hi 74Beeper,

That's the black tank flush fitting.

That line goes to an anti-siphon valve that is often located behind the shower. If you have an access panel in the shower, you may be able to see the anti-siphon valve.

The anti-siphon valve is intended to protect the campground water supply. If pressure goes negative while using the black tank flush, in theory, contaminated water could flow backwards to the campground supply. The valve prevents this from happening.

Unfortunately, the valve is made of plastic and occasionally fails. Many owners either remove the valve completely, or may cap the line and use a different method of cleaning the black tank.

If you have an access panel in the shower, take a look behind it. Maybe you'll be able to figure out what's going on.

Btw, take a look at the inside of the cargo door near the Universal Docking Center (UDC). There may be a large label that explains what everything in the UDC does.
 

Jesstruckn/Jesstalkn

Well-known member
I took possession of my 2009 Razor 3612TS last weekend. I've been going through it and getting familiar with it. This is my first camper and I'm still learning but what is the hose connection on the lower left? (See picture... it uploaded sideways)
I know the upper right hose connection is city water. I hooked it to city water and it flows out of the fuctets. But when I hook to the lower left hose connection, nothing happens. The water just deadheads. I called Heartlannd and they weren't much help. They said it could be a black tank flush but really not sure because they don't keep info on anything this old. (Really?)

I removed the inner panel and followed the line. It's red, goes across to the right side and turns to the rear and that's where I lose it.

If this is a black tank flush, is there another valve that's needs opening that I'm missing? Any help would be greatly appreciated
. View attachment 51408

I'm taking it that you are asking what that Black tank flush connection is for ? Is that correct ?
If you hook the hose up to that connection and turn it on it will run water to the upper side of your black tank "Free flowing" to flush out the tank. now if your saying it's not working then it could be that valve Dan is talking about or the soft white hose coming from that valve going to the tank is kinked or smashed. I've seen that a lot.

Hope that helped
Jerrod
 

JohnDar

Prolifically Gabby Member
If you hook to it, it's very possible that you won't hear it flowing. With your sewer line hooked up and a clear adapter on it, open the tank valve and then turn on the flush line. Providing the tank was empty, you should see "clear" water flowing out. I would find that (expletives) anti-siphon valve and make sure it's not dumping water inside the trailer.


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74Beeper

Member
Thanks for all the replys. I assumed that connection was the black tank flush but since it wasn't labeled I wasn't 100% sure. After removing more panels I see that it is. I found the anti siphon valve behind a panel in the toilet room. That's the culprit. The spring loaded check valve in it was stuck closed. I freed it up but i can see how this would restrict water flow and cause the flush system to not be as effective. Gonna bypass it and put a check valve at the hose connection.

Thanks again!
 

JohnDar

Prolifically Gabby Member
Thanks for all the replys. I assumed that connection was the black tank flush but since it wasn't labeled I wasn't 100% sure. After removing more panels I see that it is. I found the anti siphon valve behind a panel in the toilet room. That's the culprit. The spring loaded check valve in it was stuck closed. I freed it up but i can see how this would restrict water flow and cause the flush system to not be as effective. Gonna bypass it and put a check valve at the hose connection.

Thanks again!

Smart move! I first replaced the inlet in the UDC with a standard city water inlet w/brass check valve when it broke a few years ago. Then last year, I cut out the anti-siphon valve and replaced it with a Sharkbite check valve after it dumped water into the rig. In my floorplan, the PoS was hidden in a wall cavity and not accessible without ripping the piping down.
 

TravelTiger

Founding Texas-West Chapter Leaders-Retired
Smart move! I first replaced the inlet in the UDC with a standard city water inlet w/brass check valve when it broke a few years ago. Then last year, I cut out the anti-siphon valve and replaced it with a Sharkbite check valve after it dumped water into the rig. In my floorplan, the PoS was hidden in a wall cavity and not accessible without ripping the piping down.

If you replace the anti-siphon valve with a sharbite check valve, does it still have to be located up high above the shower? I would think this would be a good solution to reduce the plumbing run to the black tank flush and make it more efficient?


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If you replace the anti-siphon valve with a sharbite check valve, does it still have to be located up high above the shower? I would think this would be a good solution to reduce the plumbing run to the black tank flush and make it more efficient?


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.


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JohnDar

Prolifically Gabby Member
If you replace the anti-siphon valve with a sharbite check valve, does it still have to be located up high above the shower? I would think this would be a good solution to reduce the plumbing run to the black tank flush and make it more efficient?


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It wasn't above the shower, but above the toilet in a closed cavity with no access port. I secured the Sharkbite fitting to the underside of the bedroom floor so it's still above the tank. And there is a second brass check valve at the UDC fitting. Add to that a shut-off valve on the line feeding the UDC connection and it's extremely doubtful that anything is going to get into the public water system.

I don't wait until the toilet is backing up to go out and dump the tank, either. From experience, I can tell by the sound of the flush when it's ready to dump, before it actually burps.

Reinstalling another anti-siphon valve up in that cavity is not an option. Putting it behind the shower enclosure where there is a round access port puts the furnace directly under it. Ain't no way in shell I'm taking that chance. If I hadn't moved the converter and suppressor long before it failed, I would have lost both of them. As it is, I have a permanent water stain on the carpet on the bottom riser of the stairs.
 

TravelTiger

Founding Texas-West Chapter Leaders-Retired
Oh sorry John. I wasn't suggesting you do that, I should have ask can *anyone* remove the anti-siphon plumbing that is up in a wall (most behind the shower) and just add the check valves instead.

You did exactly the right thing to minimize any future problems.


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JohnDar

Prolifically Gabby Member
Oh sorry John. I wasn't suggesting you do that, I should have ask can *anyone* remove the anti-siphon plumbing that is up in a wall (most behind the shower) and just add the check valves instead.

You did exactly the right thing to minimize any future problems.


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No worries, Erika.:cool:
 
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