Author Topic: Water leak in tank flush system  (Read 5783 times)

Tom Ryan

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Water leak in tank flush system
« on: August 01, 2015, 09:18:47 PM »
Time to find an expert, this is the place to do it.
My Beaver Patriot Thunder Vicksburg IV 2006  43’ leaks water onto the Aqua-hot unit when water pressure is directed either to the Grey or Black tank flushing system.
The water trickles from a group of water lines in a hole saw cut hole in the floor or roof of the basement.
Problem:
I can not figure a way to get to it without wrecking the place. From inside the MH the leak must be in a fitting or check valve under the shower very close to the wall. Took some of the pantry and nearest cabinet in the kitchen. Can see somewhat under the shower, can almost see the group of lines, not quite. Really makes no difference, if I could see it there is no way to reach it from there.
Next move is to remove the bathroom sink cabinet, again if I do see it think there is no way I could touch it.
Hope:
Is there a way I could by-pass that leak? It only leaks when under pressure. Has anyone re-rooted the existing lines into the tanks and forget the existing leak?
Thank you in advance these forums have reduced my heartburn.
Tom and Deanna Ryan

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Joel Ashley

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Re: Water leak in tank flush system
« Reply #1 on: August 01, 2015, 09:54:56 PM »
Unfortunately Tom, I don't have a coach much like yours, although they are the same model year.  So I am no help directing you to your leak point.

But I can proffer that the vacuum breaker for the Sani-Flush system is a common failure point, and is a candidate for your culprit.  It is designed to prevent any sewer contaminant from running backward into the hose connection in the water bay.  Given the reasonably easy access to mine, I can't imagine yours being buried in a wall somewhere.  All I can help with at this point is a picture of my vacuum break apparatus in case you've not seen it yet, and will know what to look for.  Ours is along the back wall in the bathroom undersink cabinet.  The vacuum breakers are always mounted higher than the tank(s), and not too far from them.

Hopefully someone with a similar coach and knowledge of its plumbing will come along here soon to advise you.  I presume you've removed the two screws and vent on the shower's footing below the door... that does offer some minimalist view, though I'd expect your device to be higher up than that to meet installation guidelines.

-Joel
« Last Edit: August 01, 2015, 10:06:02 PM by Joel Ashley »
Joel and Lee Rae Ashley
Clackamas, Oregon
36.9 ft. 2006 Monterey Ventura IV, aka"Monty Rae"
C9 400HP Cat

harry kew

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Re: Water leak in tank flush system
« Reply #2 on: November 11, 2015, 12:11:21 AM »
Hi Joel
I searched vacuum break and found your write up
My vacuum break has started to leak at this point I could not find one so I put a 90 degree albow and joined them  together until I can find one.
My vacuum break is located in the same place as yours
My question is is there any other purpose for this valve other than been connected to the sani flush?
To work my sani flush I have to hook up a separate hose in the wet bay to a fitting to flush the tank.
I have know flush system for my gray water as far as I know
So I think my vacuum break is not hooked up to my sani flush or am I wrong
If anyone has trace out this plumbing and know if it is safe to leave this valve out
Thanks for any help, 1999 40' Patriot 3126

Bill Laatz

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Re: Water leak in tank flush system
« Reply #3 on: November 11, 2015, 01:10:03 AM »
I just had the same problem, and the leak must have been for some time, as the floor next to the bedroom sink is completely rotted away for about 1' x 2' under tile and carpet.  This is where the edge of slide comes, and I wonder if there will be a problem with retracting the slide - does it have a bottom roller at the edge that rides on the main coach floor?  I am waiting about 3 weeks before I tear it up when I will be close to a Lowes.  Does anyone know the floor support structure in the passanger side bedroom area?  Since the flush has a separate hose, is there any internal piping connections with the potable water system?  I have currently capped both lines, but would like to connect them together so I can use the flush system.
Bill & Dawn Laatz, 
Oakland, Michigan (N. of Detroit)
2006 Beaver Marquis Jade 45QSL, #38277,
Cat 525HP C-13
2017 GMC Acadia Denali toad

Joel Ashley

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Re: Water leak in tank flush system
« Reply #4 on: November 11, 2015, 03:48:16 AM »
I can't speak to your floor structure, Bill, but no doubt others here are more familiar with it.

As to connecting the lines, as apparently Harry has done, I think the only negative aspect is that the vacuum break is there for a reason - to help prevent contamination from backflow of hose, fittings, etc., but mostly the water source.  To my notion this is very unlikely, but then again that's why backflow devices of many types are available for protecting various water resources, public and private.

I would be careful flushing though, and use a pressure regulator on the hose... I keep one on my separate flush hose.  You don't want to blow off your spray heads into the tank... they are sensitive to that possibility.

I think mine is not in perfect shape either, since some water backs out of the water bay connection when I remove the hose... it didn't used to do that.  But I use a separate hose especially for the flush function, and rinse it for a few seconds before draining and storing it.  I think as long as you use common sense efforts to counter any possibility of contaminating anything, you should be good until you can replace the valve.

The Sani-Flush system, when used regularly, is a great way to keep sensors from fouling and dump valves from jamming, etc.  The gray tank, Harry, gets kitchen detergents, other soaps, and perhaps even laundry detergents.  It's going to be by nature "cleaner" than the black tank.  At least the gray tank will naturally suspend and flush solids much better than the black, so only the addition of the occasional tank treatment might prove helpful.  I often pour Thetford enzyme formula in the traps if they sit unused for awhile.  But each owner has their own preferences.

Joel

« Last Edit: November 11, 2015, 03:53:04 AM by Joel Ashley »
Joel and Lee Rae Ashley
Clackamas, Oregon
36.9 ft. 2006 Monterey Ventura IV, aka"Monty Rae"
C9 400HP Cat