Serious Plumbing Considerations

[Jon Wehrenberg]

Lew made mention of a flush valve problem we had on the trip to FL, but once we get past the toilet jokes we get to the serious core of the issue.

The following applies to Head Hunter toilets and flush valves but may also apply to other products.

In the plumbing industry the cardinal sin is cross contamination. Every single plumbing code in the country has extensive regulations to prevent the possibility of waste water entering the fresh water supply system. Our coaches with the aforementioned toilet and flush valve would likely never be accepted by any of the building codes relating to plumbing. I am sorry for the length of this, but it is important for all coach owners to completely understand the following otherwise they might as well brush their teeth with water from the toilet, unless they already have.

The HeadHunter toilet operates by having a very high volume flow of water create a low pressure to evacuate the toilet bowl. A diaphragm valve is caused to open, the flow of water is actuated and in a short period of time the valve closes and the water stops flowing. The problem begins if the flush valve fails to turn off the water flow. The response is to turn off the pump or municipal water supply. Here is where every owner needs to look at his or her coach. If the water supply to the toilet can be isolated and shut off while maintaining pressure in all other water systems in the coach (such as the sinks and shower) there is a potential for cross contamination but it is slight.

If the only way to turn off the flow to the toilet is to shut down water flow to the entire coach you may have a serious problem. When the house water pressure drops to zero with a flush valve that will not shut off the flow to the toilet, the valve is open. With zero house water pressure and a ball type check valve in the water system it is probable the toilet contents will backflow, through the flush valve, and into the fresh water tank. It is less likely if the coach is equipped with a spring type check valve. All chack valves are more efficient if the water pressure on the downstream side is much higher than that on the upstream (pump) side.

If you store your coach with the pump turned off and the water pressure bled off the potential to create this contamination condition exists. The only sure way to prevent cross contamination is if there is an air gap between the water flow source and the soiled water, and with the toilet design that is not possible.

I never studied my system when it was working but when it failed to shut down on the trip to FL I studied it to determine how it worked and I now have a fresh water supply to sanitize. The toilet and valve are elegantly simple and as such should prove very reliable, and are very easy to service, but since the toilet will backflow into the fresh water tank under certain conditions it would be wise for everyone to at the very least understand their own coach system and determine if they can assure themselves of a means of prevention.

[Joe Cannarozzi]

Jon I keep reading this over and over and either Im missing something or you have mistated something. If the toilet can be isolated that is good, right? Or are you suggesting that one way its a slight problem and the other way its a serious problem but either way is incorrect? Furthermore I'm pretty sure, you, would not have that problem of pressure bleading off and that further confuses me. Please clarify for dummy me.

By the way hate to have missed you that morn. a few days back. I'm guessen you overnighted at the 2mm at the Flying-J? We pulled in there for fuel right after we saw each other. I had just gotten done mentioning to Debbie to keep her eyes open for someone heading South and then there you were!

[garyde]

I believe what Jon is saying is that his toilet ,for the fresh water supply, has no check valve, so if the flush valve fails and you can not stop the water from flowing thru the toilet, you will have back flow from the toilet the minute you turn off the water pump or city water. The back flow from the toilet would drain back towrds your pump and fresh water tank.
This would be a worse case scenario depending upon how your cold water pipe is plumbed from the toilet back toward the pump and tank. If there were T's in the line, and or wheter the toilet cold water pipe was plumbed vertically up the back wall high enough to create an air space.
My question would be ' what was Liberty's opinion on this?' Gary

[Jon Wehrenberg]

This is not a converter issue so I am not going to even try to opine what the position of Liberty or Vantare or any other converter using this type of system is. From many years of teaching seminars in the plumbing industry I have learned our coaches are huge compromises and among the compromises is a plumbing system that fails muster with respect to building codes but works. My concern is that all owners understand the risks.

We have never used water from our faucets for ingestion, and this only reinforces our decision that was made in 1990.

Gary's answer to Joe was right on target. I am going to add some valving to our coach to minimize our risk, and will provide detailed information. I do know some of the converters have installed spring type check valves which will help, especially those with Headhunter pumps.

I will tell you I am disappointed this issue has never been widely discussed by anybody, and it is my opinion the installation of spring type check valves was probably not done to prevent cross contamination, but because it was an engineering requirement to make the pumping part of the system function properly.

[Joe Cannarozzi]

It was suggested to me, I'm absolutly sure with good intent, in another post of another thread, that I might be trying to reinvent the wheel.
Hmmmmmmmmmm.

[JIM CHALOUPKA]

Karl M., How are these plumbing issues addressed in the boating world? It seems to me they would be quite similar. Wouldn't three separate pumps work here. Drinking, Grey,Black. JIM

[Jon Wehrenberg]

Joe, We waved and I grabbed the CB, but I now remember you don't use one.

The plumbing issue would benefit from fresh thinking. To be safe there needs to be an air gap between the waste and fresh water side. That way the waste water cannot flow back into the fresh water tank.

Jim, the problem is unrelated to pumps or the number of them. It is the principle of how the valve works. That particular valve in concert with the toilet piping sets up a high speed high volume momentary flow that evacuates the toilet bowl by creating a low pressure area in the bowl. As designed it would not work with any kind of air gap.

In your quest to find the perfect coach don't dwell on issues like this one because there are ways to minimize or eliminate any cross contamination as long as the system is well maintained.

[GaryB]

HELP! We are very new to this. We have a 2006 Liberty. Yesterday we noticed a foul smell. (Our bus has been parked for about a month at our new farm. Having had to replace the space heater in the water bay, having first drained all the water, all the water in the fresh water tank was new a week ago.) Back to the smell. We Searched and found black water had backed up from the shower drain. The black water tank was about 15% filled. My wife noticed the gray water bypass was closed and opened it and the water drained from the shower. We put some clorox down the shower and washed the shower pan.
We had something like this happen a few months ago out on the road.
What are we doing wrong? Why would black water back up into the shower when the tank is almost empty and why would it drain when you open the gray water bypass. We're in Dallas and what I know about plumbing is even less than I know about electricity. HELP. By the way, if anyone could talk to me or email me about this, that would be wonderful. gary.lawson.lawyers@gmail.com or 469.964.8500 thanks 2 million!

[Joe Camper]

Here's what I think is going on. On your Liberty you do not have separate grey and holding tank there's just one.

You have Headhunter tank sensors and possibly your tank sensors need to be calibrated because what it's saying it's 15%. It's completely full.

By opening the gray water bypass it lets everything out onto the ground except for the contents of your holding tank so that's why it drains out when you open up the bypass, that is working correctly.

In my opinion there is 2 things that could be causing this and calibrate the tank level sensors is one of them. Headhunter has a very easy process for you to do that.

If you go to the remote panels for the tank level sensors and take the four screws and pull the panel away you will see some dip switches on the back of those panels we're all the little red lights are and you calibrate those tanks first empty and then full. If u r lucky that's all you need to do.

However before u do that check another component first.

Another thing with the Headhunter tank level sensors that could be causing the bad calibration. There's little quarter inch push in Street elbows at the top of the tank where the airline goes into the tank and then down. If those Street elbows failed and they r leaking air it could be that causing the incorrect t level. It could also be the micro compressor the little micro air compressor that they use could have failed as well but prob not in this case.

I would go to those little push in fittings the street elbows on the top of those tanks check there first, those fail all the time. If it's not the street elbow then calibrate the tank.

I think you could test the micro compressors there is a little red reset button on them and there should be a green light for them on the compressor. There r 3 of these they look like a small fish tank air compressor.

If it seems like it's kind of complicated all this to go through for your tank level sensors well you'd be right because it is. I do not care for Headhunter I think their systems r over complicated and overpriced.

If u go through the house manuals Headhunter and calibration procedure will be in there or they also have it online.

If the airline at the elbow is leaking snip a short bit off the end and reinsert it.

[Gil_J]

Agree with Joe. Your tank is full.

The first thing I would do is make sure the flashing LED on the bottom of the micro pump is flashing green. If it's flashing red there is a leak in the line. If it's flashing green, disconnect the hose from the bottom of the pump and blow it out. It's possible debris is restricting the air/fluid flow in the tube in the tank.