Jump to content
Sign in to follow this  
tbutler

Black water flush system caution

Recommended Posts

A friend of ours always kept his black water tank flush hose hooked up to the water faucet when parked for an extended time. As is standard practice, the black tank was kept closed except to dump as it neared full. One time the water was shut off in the park. Park personnel being helpful came around and shut off the water at each of the affected coaches before the water was shut off. Our friend was not home. He wasn't at home either when they returned to turn on the water. Evidently the person who turned the water back on was different than the person who turned it off or they simply didn't remember that only one hose was on. They turned on both hoses. Since the flush hose puts water into the black water tank under pressure, there is nowhere for the water to go but up. Our friend came home to find the black water tank overflowing through the toilet. Needless to say they had some repairs to do. The moral of this story is to always disconnect the flush hose from the faucet and the black water tank. No mistakes this way!

Share this post


Link to post
Share on other sites

OH SH*T-lesson learned.

That is what I like about the RV sani-con system. You don't need to use the sewer flush valve as I can transfer the grey into the black which does a real good rinse of the black tank with the soapy grey water.

Share this post


Link to post
Share on other sites
Guest Wayne77590

I have heard other horror stories and I have seen one horror story of an overflow. Not a pretty sight at all.

I use a quick disconnect on a separate hose. I even sometimes become paranoid and shut the water off at the spigot when we go sight seeing. If there is a leak or whatever, I want to be present if it happens. It takes me less than 30 seconds to turn the spigot off or on.

Thanks for reminding me.

Share this post


Link to post
Share on other sites

Wayne,

Aren't those quick disconnects great? I gave up screwing on hoses shortly after we began full timing. All my hoses are set up with quick disconnects. I use a hose splitter (Y) off the main faucet with the quarter turn on-off to control my water. One side is for fresh water and the other side has a vacuum breaker to prevent back flow and is used for tank flushing and/or washing vehicles, etc. I found a really good Y last year. Goodyear makes a nice plastic and rubber Y with large valve handles. It is more expensive than the brass ones but seems to be very durable. The old brass Y's haven't been the most durable or highest quality in my experience. The Goodyear Y and hose vacuum breakers are available at Lowe's or Home Depot. I also use brass angled shut off valves to change the direction of the water spout. I don't know who designs some of these connections but I have seen some really weird and unhandy connections for both water and sewer.

I keep an adjustable pliers in my utility compartment for the difficult connection that must be screwed on/off. I also keep one in my handy tool box under the second step inside our coach entry. I can open the door to the coach, lift the step and grab the tool that I need. I only keep the most used tools in that compartment. The real tool boxes are in a basement compartment on a slide tray. Perhaps we should have a forum for tools. But enough about that...

Share this post


Link to post
Share on other sites

I also use a y valve with quick disconnects. I use opposite genders so that the fresh water hose will not fit on the flush tank connection and vice versa. Plus I have a back flow stopper and triple cut-offs on the black connection. One at the valve, one on the end of the hose and one on the flush connection itself. I turn on all three to flush and turn off all three when done. It keeps accidents from happening as long as I don't forget of course.

Share this post


Link to post
Share on other sites
Guest Wayne77590

Tom,

So right on the disconnects. I was in a store, and can't remember which one (CRS - Can't Remember Store), and there was this package of two plastic disconnects. I had to do a double take as these were different. Instead of being push-on, they were "side slide-on." I had misgivings that they would not leak, but decided to buy a package anyhow being the tech geek, having to have it when it first comes out type. Wow! I thought peanut butter was a great invention! The connectio is made by sliding on "from the side" onto the other. It didn't leak. Next time I see a package of them I'll get a name and post on the forum.

The other disconnects I like are the brass(metal) ones with the black plastic knurled nobes for these old hands. The problem is that the hard water attacts the metal and they leak after a short period of time. Maybe I'll keep a solution of 50/50 vinegar and water to spray on them when I'm through for the day.

I keep a couple pressure valves on hand to prevent back flow. I also bought one of those blue coiled hoses and use it exclusively to back flush.

I use the 4 spigot brass adapter. I like that little 1/4 turn for full flow option like you do

Gramps,

I would have to be completely color blind to mix up my hoses. The only thing that touches the fresh water inlet is the white potable water hose. All of the colored hoses will leave a bad taste, whereas the white are potable hoses designed safe for consumption.

Hmmm! What year did they come out with "potable water hoses?"

.

Share this post


Link to post
Share on other sites
Guest ekaren
OH SH*T-lesson learned.

That is what I like about the RV sani-con system. You don't need to use the sewer flush valve as I can transfer the grey into the black which does a real good rinse of the black tank with the soapy grey water.

So how do you transfer the grey into the black to rinse? Sounds like a great flush!

Share this post


Link to post
Share on other sites

If you plan ahead and add a small inline shutoff valve at the flusher input you don't have to worry about someone accidently turning on the water at the hose bib. This way you don't have to disconnect the flusher hose each time you flush the tank. I purchased one in Home Depot's garden department for about $2. I shut off the flush hose at the flusher input and close the door. I also shut it off at the hose bib. I have done this for the past 7 years as a full timer using both methods of dumping (4inch waste sewer hose or Sani-Con System) without anyone accidently turning it on since they would have to turn on 2 valves, one of which is inside the compartment.

Share this post


Link to post
Share on other sites

You don't have to unhook the backflush hose if you add a shut off valve on the end of the hose inside the compartment where the hose hooks on the back flush. I had the park turn off the water and later turn it back on and turned both legs of my Y connector on. I was lucky enough to return shortly after and could hear the noise from the flusher running in the tank. Ishut it off before it overflowed and installed shut off in compartment where no one has access.

Share this post


Link to post
Share on other sites

How to transfer the gray water into the black water tank for a rinse? I have a flo jet macerator on our system. After dumping the black water tank I can simply open the gray water valve. The macerator doesn't empty the tank like the 3" hose does. The gray water will back up into the black water tank. Shut off the gray water after a few minutes and let the gray water drain out of the black tank. You can repeat this if desired. When finished, simply close the black water valve and open the gray to let the rest drain out.

Now, having said that... If you want a really good flush, dump a bucket of water directly down the toilet and see what comes out after the above rinse. The hose on the macerator is transparent so I can monitor the nature of the effluent. I have a clear adapter on the 3" hose when I use it. I have a built in spray rinse in the black water tank. Using the gray water back flush and the spray rinse, water from the black tank will flow out clear. Then dumping a bucket down the toilet directly brings out another charge of dark effluent and paper, etc. Check it and see what you get. I have three 2 gallon buckets that I use for washing, etc. When it is time to dump the black water I'll put 2 or three of these down the toilet to get it to finally run clear.

Share this post


Link to post
Share on other sites

Hey that bucket flushing Idea is great. I'm going to give that a try. I have a built in spray system in my Black tank. It normally work perty good. But some times I can see small pieces of paper still coming out. I'm sure the buckey of water will do the trick!!!

Thanks :rolleyes:

Share this post


Link to post
Share on other sites

Having worked on several black tank issues, I have found the best way to flush a black than is to allow it to fill with waste ans chemical to at least 3/4 full and go out and pull the drain handle, when it is through just shut it and step back into the coach put another dose of chemical and add a couple of gallons of water through the toilet. Allow the chemical to do what it is supposed to do, break down waste and deoderize the tank.

I have dropped several tanks that needed to be replaced because they were damaged by overfilling with a flushing system. I had one customer run me down on our way out of a park last year after him and a friend returned from a golf game. He remembered that he needed to drain his black tank, after draining the tank, he turned his flusher water hose on (with his drain valve closed). If you check most coaches with a tank flush fitting you will find a label that tells you only use with the drain valve open. His buddy came over with a beverage and the water hose was soon forgotten. He quickly remembered he left it on when he heard a loud "thud". His new fifth wheel had just lost it's black tank. It broke fittings, bent the mounting rail beyond reuse, tore up the underbelly liner and just made a big mess.

I had another customer that left his hose connected. He called me early one morning and said his toilet ran over during the night (he had gotten out of bed and when his feet hit the floor they got wet.... When he called and said the water was comming out of his toilet bowl and the pipe was full too, I told him to go and check his flush hose cutoff. He said someone had turned it on just a little bit. The park he was in had several Long term People with kids that was allowed to roam the park. The customer figured one of them saw him and played with his hose cutoff and left it on as a prank. Weather this was what happened or not, it was a mess.

After flushing out the black tank several times in a row with a flush system using a water hose, we have dropped a tank for replacement. There is still a "sludge" in the tank. I know there are many ideas about flushing out a tank, just ask anyone how they flush theirs. However, if you just fill the tank to at least 3/4 full, there should be enough vacuum as the liquid leaves the tank to pull most of the "sludge" with it. The rest can be taken care of by chemical and water left in the tank.

As most motor coaches have their tanks in the compartments, it is not a great idea to overfill the tank to the point of damage with a water hose attachment. Depending on how the mfg attaches the vent pipe or the fill pipe, you may only have a grommet fitting in the top of the tank. Overfilling the tank may lead to some waste water to run into the compartment. This can only lead to a mess that not many people want to deal with.

Share this post


Link to post
Share on other sites

midgarvservice,

Great information, thanks for adding your experiences. They should serve to make everyone more cautious.

Share this post


Link to post
Share on other sites

i'm working on a black tank flush in a rig that the owner did not use a pressure regulater when he hooked up the flush hose. after about3 min he heard a load pop followed by rushing water. the water got his power converter too of course as it was mounted under where the leak occured.

when i started in to it, i had to take the panel off the wall behind the toilet, and there it was a plastic backflow valve to keep the black tank from overflowing back out the rinse hose, it had come apart at the seams and all this ensued.

the bad part, or worese for him, was his continued service plan will not pay for the repairs cus they were not covered in the policy. :rolleyes: so if you use the blacktank rinse, it has the same resrtictions on pressure as the rest of your plumbing! i know i have been guilty of not using a press reducer on my tank flush as well, but not any more!

steve sandidge

camping world rv univ

class 54

91 rambler imperial

Share this post


Link to post
Share on other sites

Please sign in to comment

You will be able to leave a comment after signing in



Sign In Now
Sign in to follow this  

×
×
  • Create New...