Black Water Tank Inlet Flush Line

[gebills]

I've done some digging in the archives and have not stumbled on to discussion on this inlet line so, I'm gonna ask the forum. My question is in regard to the polyethelyne "black-water flush line coming into the RV from the back of the docking station. I'm trying to take care of all of the drips we've found in mostly PEX tubing connectors after initially picking up our BH3455RL this past fall.

The leak I'm currently working on is in PEX tubing that attaches on to the piece of polyethelyne hose coming in from the black water flush connector at the docking station. The PEX tubing carrying the flush water (in a blue PEX hose) up from the basement overhead and up about 3 feet into the back side of the shower wall, makes a loop up in the vacinity of the circular inspection opening by the shower on/off valve, where it connects to what appears to be a vacuum breaker type plastic device. Coming back out of the blak round device, the factory has put on a red PEX tube that drops back down the same 3 feet and back down to the basement area. At that point, it elbows and travels over to the starboard side of the utility area in the basement, where it connects back into the polyethelyne/braided hose and I presume heads over to the black water tank for the purpose of flushing.

My question is: is this small round device a vacuum breaker in the black water flush line? Would it be for the purpose of not allowing any tainted water to back out of the black water tank and out through the inlet inlet black-water hookup connector in the docking station? I'm not finding any kind of plumbing diagram so as to identify this small round black plastic device. Attached is the best picture I could manage to get of this black device. thanx for responses ~ gebills.

 

[Ray LeTourneau]

gebills, you are absolutely correct. Anti back flow or vacuum breaker for the black tank flusher. It's nice to see you have easy access to it. There have been a few issues with them leaking a bit or malfunctioning in some way. Not many, but a few. In most rigs they are hard to access.

 

[jnbhobe]

gebills; You are right as to what your looking at, and the purpose. The thing about Pex is to have the right connectors Pex and hose use different clamping methods. Pex uses copper rings or ratchet clamps and brass fittings when you can. For the braided hose weather black or white you need a sprial hose clamp or automotive mini-clamp. I carry a one-handed Pex crimping tool with me and new brass fittings with me as well as them two pieces that went up the wall to the vacuum breaker, one hard pull and it fell right out. lol

 

[gebills]

Thanx for the replys fellows. Although it is a little difficult to see in through the round service opening in the shower wall, that is what it appeared to be, i.e. a anti-siphon or anti-backflow device. As I see that many owners are as perplexed with the PEX fittings and clamps as I am becoming, the tubing seems to be a very good quality tubing; it's just that the fittings and clamps are turning out to be not so user-friendly and tend to leak.

After much work with the dripping under the galley sink, I ordered and installed some Flair-It fittings to connect the PEX tubing to the sink faucet supply tube lines. The Flair-It fittings were 1/2" flair X 1/2" female NPT adapters. I tried and tried to seat the 1/2" male metal supply line fittings into the female poly adapters with no success. Finally went back to the Flair-It web site and found a small note warning against trying to seat a metal NPT male fitting into the poly Flair-It NPT fitting. I went out and bought a couple of GatorBite PEX hose X female pipe adaptors from HD, and life is good. Those things seal so quick, it make me wonder why more people aren't aware of them.

With my current project of replacing the PEX fittings and their respective clamps on this Black Water Tank Flush Line where it elbows up into the coach shower wall and back down to the basement area, I think the Flair-It fittings will work fine because i am not using any NPT threaded fittings anywhere in this black water inlet supply line application. Not being able to use the black water flush line is fustrating, and it just gums everything up in the black water tank so trying to get these fittings replaced is kind of a priority. Thanks again for the responses. gebills

 

[bdb2047]

Something else to check with vacuum breaker valve.I just found it leaking thru top of valve not at fittings.There appears to be a plastic valve that closes with water presuure and opens when pressure is off.Took valve out and washed out with water.Is working O.K. for now.It was leaking pretty good not just a drip.I am guessing there was some kind of dirt/contamination where valve seals.I will replace it.This will become one of the routine checks for me have no idea how long it was leaking as I never looked at it while it was in use before.

 

[porthole]

Jon - I have been using the ratchet crimps with the regular hose with success. I have only been using it on brass fittings though.

I went out and bought a couple of GatorBite PEX hose X female pipe adapters from HD, and life is good. Those things seal so quick, it make me wonder why more people aren't aware of them.

Price.

 

[gasman]

Is there any reason that those pex lines couldn't be cut loose and then, behind the basement wall, simply install a check valve on the flush line? I realize the check valve could possibly fail, but so could the back flow preventer.

 

[jnbhobe]

Thats why the vac breaker is mounted higher than any other water line in the rig. Also is a RVIA reg of some kind.

 

[gebills]

You were right bdb2047; the drip from this black waterinlet flush line was not in the PEX fittings in the overhead of the basementarea. The leak is coming from the black plastic vacuum breaker assembly insidethe wall behind the shower inspection port hole up in the cabin area. I've beenso perturbed with these PEX clamps that I was blaming them before I had a goodchance to get in and analyze what the problem really stemmed from. As we were getting ready to pull out ofMcMinnville Oregon this morning to head for home, I charged the black waterflush line from the docking station while DW was in the shower area with aflash light. Sure enough, the water leakis coming out of the top of the vacuum breaker that is mounted behind theshower wall. I haven’t pulled it outyet, but it will have to be taken care of before we head out with the RVagain. The water leak was rolling outabout a cup of water per minute, so it is pretty noticeable. I appreciate the heads-up on this.

 

[StephenKatSea]

You are very fortunate that the VBCV is mounted behind your shower near the round access port. In some BHs it is actually mounted WITHIN the wall behind the toilet with absolutely no access. This MUST be against industry standards and regulations. It is virtually impossible to see this VBCV which can allow leaking water to flow down upon electrical items mounted below within the basement area. 2008 BH 3670s, in particular, suffer from this very poor arrangement. As yet, I have seen no comment from Heartland on this issue. We continue to really enjoy our 3670. But, this one item is beyond wrong.

 

[Bobby A]

It looks like this thread is not that old and I had an issue arise today that I would like to get some feedback on. I was flushing my black tank today and heard an unusual noise, so I shut the water off and opened the round access port in the tub and had the wife stand there watching while I turned the water back on. Sure enough it was leaking a little bit and making noise. I would assume the vacuum breaker went bad ?? Is this a standard part that most RV stores carry ?? Thanks

 

[Toy1Ton]

I wounder if their is a bass one made to replace it?

 

[cookie]

I wounder if their is a bass one made to replace it?

Well, you might have to do a little plumbing modification.
I did a little search and HERE is a page full of brass vacuum breakers.

Peace
Dave

 

[Ray LeTourneau]

It looks like this thread is not that old and I had an issue arise today that I would like to get some feedback on. I was flushing my black tank today and heard an unusual noise, so I shut the water off and opened the round access port in the tub and had the wife stand there watching while I turned the water back on. Sure enough it was leaking a little bit and making noise. I would assume the vacuum breaker went bad ?? Is this a standard part that most RV stores carry ?? Thanks

Bobby, a humming or vibrating type noise is normal. Mine is one of those behind the crapper so I can't get a visual of it but I think they are connected with fittings that are the same as the kitchen and vanity fixtures. If you can reach the vacuum breaker, try to tighten up the connections and see if that cures the leak.

 

[Bobby A]

Bobby, a humming or vibrating type noise is normal. Mine is one of those behind the crapper so I can't get a visual of it but I think they are connected with fittings that are the same as the kitchen and vanity fixtures. If you can reach the vacuum breaker, try to tighten up the connections and see if that cures the leak.

Hi Ray,

This is a different type of noise than I am use to hearing, I know the sound of how it usually is and this is different. Does anyone by chance have a Heartland part # for the vacuum breaker ?? Ray, give me a call when you set settled in in Port Richey, I have several gigs and things going on that you might like to join us, give me a call or PM me.

Bobby