Black Water Flush Valve - Water Leaking Under Nautilus System

[Andy+Mo]

I recently ran water into my black water flush valve while draining my black tank. I had a pinch in the water hose and when I released it there was a surge of water into the valve. Then I noticed water dripping from under the side of my camper -- not from under the Coroplast but from under the side nearby the water heater area. (directly south of the side compartment containing the Nautilus system.) The water was running down propane lines that travel up from the main line to underneath the heater and water heater. It seams that water is leaking now under the side and the hole where the propane lines run through the sub-floor area is just an "opening" for the water to escape. UGH! Gonna probably have to take it in to get looked at. When I turn off the flow of water into the black water flush valve the water stops flowing down. I was afraid there was worse damage but leaving the fresh water intake hose connected and under pressure does not produce any leaking. I was able to get through the rest of the week of camping and head home. (GD 2017 Reflection 303RLS)

[ncitro]

I would suspect the connection at the vaccuum breaker on the black flush line. This is normally located behind the shower as it needs to be higher up than the tank. It is usually accessible through an access in either the shower itself or on the wall on the other side.

[JBill9694]

Your freshwater plumbing, Andy+Mo is separate from your black tank flush pipe which only goes to the spray nozzle in your black tank (several threads with diagrams and photos discuss this routing so I won't go into anymore detail). As ncitro , suggest it could be the vacuum breaker on your black tank flush pipe, or could be a loose fitting on the back of the Nautilus panel. Being somewhat methodical in nature I would access the back of the Nautilus panel and work my way from there towards the vacuum breaker and the black tank. This will also give you a chance to make sure that all the water did drain out through your apparently unplanned drain holes.

[Canyonlight]

Andy+Mo - here is what the black tank flush vacuum breaker looks like behind the shower panel in our 303. Removing the panel (not sure if yours in the same) was as easy as removing the 4 screws and pulling the access panel away from the shower stall wall. I resealed after re-installation using clear silicone. I removed our panel to check the fittings on the cold and hot lines to the faucet.

If you have a leak in this area, you will be able to see the water on the lines, vacuum flush, wall, floor, etc. Keep us posted

Dan

[Beachcamper]

If you open the door that is on left side of hutch, you can see the back of the water heater and between it and the furnace is where water would pool IF that valve posted in canyonlands photo above was leaking. That is where the shower lines are located, just above that area.

[Andy+Mo]

This feedback all makes good sense to me. I will need to open the shower panel and take a look. Maybe have my wife run water to the black valve while inspecting that vacuum breaker. If there is a leak there I am wondering if I will be able to reach in and remove it or adjust the hose connection. I don't have the cover off yet and will have to take a look later today or this weekend. Does anyone know from experience if it is difficult to get your hands in there and remove the vacuum breaker or even tighten the connections? Looks difficult to work with.

[Canyonlight]

This feedback all makes good sense to me. I will need to open the shower panel and take a look. Maybe have my wife run water to the black valve while inspecting that vacuum breaker. If there is a leak there I am wondering if I will be able to reach in and remove it or adjust the hose connection. I don't have the cover off yet and will have to take a look later today or this weekend. Does anyone know from experience if it is difficult to get your hands in there and remove the vacuum breaker or even tighten the connections? Looks difficult to work with.

Andy - I could and did reach into the back corner of the shower to tighten the hot and cold fittings abit with no real difficulty. I could also reach the VB in ours as it was high enough. All fittings were snug and we had no leaks from any of these fittings. Now this said, I am an average size guy - a large guy with large hands/arms may have a little more challenge.

Dan

[Andy+Mo]

Thanks Dan - I am very average...you can ask my wife and kids!

[Andy+Mo]

So I pulled the cover and the vacuum breaker is right in front of the opening. We ran a little water into the clean out valve and water came out through the vacuum air port. I am guessing I should order a new one and replace.

[ncitro]

So I pulled the cover and the vacuum breaker is right in front of the opening. We ran a little water into the clean out valve and water came out through the vacuum air port. I am guessing I should order a new one and replace.

Correct, no water should come out of that.

[Canyonlight]

and, Andy - a number of folks have replaced it with a higher quality metal one. I am not familiar with those but hopefully someone will chime in who has done so. Possibly Rob Cate&Rob may have done this or may recall who has and can shake those trees.

Thanks, in advance, Rob !

Dan

[Cate&Rob]

Andy+Mo ncitro Canyonlight


It is important to note that per the vacuum break manufacturer, a small amount of water from the vacuum break is "normal".
(Which is why I have always questioned the location in a 303RLS directly over the furnace control board . . . but, I digress)

From the B&B Molders (manufacturers of the OE vacuum break) installation information . . . "Water leakage from Vac/Check is likely when water pressure in supply line is under 8 psi. It is normal for a small amount of water to escape Vac/Check as plumbing line for tank flush pressurizes." (See Pg 4 of attached)

So, back to Andy's observation . . . does the leak stop when the flush line comes up to full pressure? If so, the vacuum break may be operating as designed. From the earlier description of the amount of water leaking out, I would still look carefully for a leak at one of the vacuum break connections when operating at full flush flow & pressure.

Rob

The-Flusher2-Install-.pdf

[Andy+Mo]

Rob - I read the doc and noted the leakage when the pressure is under 8 psi. Couple of things. I ran the water for just a few seconds because I did not want a lot of water running down into the cavity. It was connected to my house so I am guessing the pressure was good. But, I may have to try it again. I did not observe leaks from the hose to valve connections as I did look at those while it was running. I can't think of where else the water would be coming from. I have the new OEM B&B part ordered already...thought about upgrading to brass...might end up being a mistake. Also, I cannot open the black tank when running the test because the trailer is in my driveway. I am not sure that keeping it closed while running the test would cause an issue. Obviously the instructions say to run it with the tank open. When I was getting a fair amount of water flowing from the side sub-floor area (back at the campground) the black tank was open. I did not see any water leaking from under the Coroplast inside the main frame. I may run the test again before installing the new valve. Again, the water really leakes out of the camper where the gas lines run through the sub floor from the supply line connection on the frame. It would seem like it has to be that valve. I did not look at the back of the Nautilus system. Guessing I would have to empty the storage area and peel back the felt wall to see behind it.

[Cate&Rob]

Andy+Mo
Hi Andy,

There is no problem running the flush into a closed black tank. The advice to do this with the drain gate valve open is only to make sure that someone does not “forget” that the flush line is filling the tank. As suggested earlier, if you open the left door of the buffet (it may be screwed closed) you will be able to see the water heater and further in, the side of the furnace. If the water is coming from the vacuum break, you will see it dripping down the side of the furnace. To get a closer look at this area, pull the bottom drawers from the buffet.

Rob

[boyscout]

It is important to note that per the vacuum break manufacturer, a small amount of water from the vacuum break is "normal".

I recently bought a quality brass Watts valve to replace ours on the black flush sometime and was disappointed on getting it home to see that warning in its box.

The warning made me think about routing the black flush line and vacuum break valve elsewhere where water leaking from the valve won't be hidden and damage things. It's currently between the shower wall and the pantry wall, like many of them.

However it should be higher than the toilet in the trailer, not just higher than the black tank, right? Even though the black flush is a system unto itself, not connected to any other plumbing, it is connected to the black tank and therefore its breaker valve must be higher than anything that feeds into the black tank.

Do I have that right Rob? Because if I do that limits the options for re-routing the black flush system to put the vacuum breaker valve in a more-accessible and less risky (valve leaks) place in the trailer.

Thanks.