Water Pouring Out of Roof Vent

[jgaryclark]

2021 Jay Flight SLX 267 BHS


Sunday morning gray tank was full. Dumped about 25% of it. A couple of hours later I dumped the black tank. After it was empty I connected the hose to wash out the black tank. Everything seemed to be going fine but after a couple of minutes, water (looked clean) started pouring out of one of the roof vents. I immediately turned off the water at the source and it eventually stopped. I tried to open the valve to empty the black tank again but it was much harder than the normally easy pull. When I crawled under the trailer to get a better angle to pull at it, I noticed water leaking from the enclosed undercarriage. I tried to push up on it but it was heavy heavy heavy full of water. I finally got the valve open to flush the black tank and emptied it and the gray tank.

What did I do wrong? I've done the same exactly process every time I've emptied the black / gray tanks (as my dealer had instructed me to do) and never a problem.

I turned the water source back on (only to the city water connection) and no leaks anywhere.



Any ideas what might have happened?

[bankr63]

Total guess here. When you dumped black, did it take a normal amount of time? I'm thinking your dump pipe got clogged making it look like it was done. Probably at the valve, which might explain why it was hard to open again. With the tank still partially full, turning on the black flush could have quickly overtopped the tank causing it to spout out the vent, and probably some overflow from the vent piping or toilet line leaking into the underbelly.

Again, just a guess using some inductive reasoning. Others may have better ideas.

[Marcm157]

Did you happen to leave the black tank valve closed when you flushed the tank? I agree with Bank it sounds like there was some obstruction or a closed valve. I close my black tank valve when using my flush but I will NOT walk away from the trailer or do anything else while I have it running. I repeat this closed / flush/ open cycle a few times.

[jgaryclark]

Originally Posted by Marcm157

Did you happen to leave the black tank valve closed when you flushed the tank? I agree with Bank it sounds like there was some obstruction or a closed valve. I close my black tank valve when using my flush but I will NOT walk away from the trailer or do anything else while I have it running. I repeat this closed / flush/ open cycle a few times.

That's exactly how I do it...flush black tank, close valve, run tank flush for a minute or 2, open valve, repeat. Finally, close valve, run it for 2 minutes then shut off water. Then go to the toilet and drop in some chems.

[jgaryclark]

Yes...it took what I consider to be a normal amount of time.

[Dbunke]

A wise old guy once told me, never use the tank flush with the valve closed..Unless I wantd a shower from above...

[garywilson]

Bath floor get wet?

Guess at how much water leaked from under?

[Fiss1068]

Any time you connect the flush hose, you have to keep the gate valve open for the black tank. Don't close the gate valve when flushing the tank.

[jetlag]

Originally Posted by Marcm157

Did you happen to leave the black tank valve closed when you flushed the tank? I agree with Bank it sounds like there was some obstruction or a closed valve. I close my black tank valve when using my flush but I will NOT walk away from the trailer or do anything else while I have it running. I repeat this closed / flush/ open cycle a few times.

Originally Posted by jgaryclark

That's exactly how I do it...flush black tank, close valve, run tank flush for a minute or 2, open valve, repeat. Finally, close valve, run it for 2 minutes then shut off water. Then go to the toilet and drop in some chems.

Exactly what I do, plus I have the BMPRO app with me as well. When it reads 3/4 tank full, I dump and repeat until water comes out clear. I then add about 3 gals of water and a scoop of happy camper.

[TWP723]

I empty the black completely. Once I have nothing passing the clear elbow, I attach to the flush valve and leave the valve open. I expect to start seeing dirty water flowing past the elbow almost instantly. If I don't, I shut the water off and investigate. It's happened to me once and the black tank drain was clogged and holding water. Got out the wand and went to work. My wife kept watch as I was rinsing from inside. She banged on the wall and said a large amount just went by the elbow. So yeah...the drain or valve could be clogged. I would imagine it would have to be a serious clog to retain the amount of water it would take to drain out the top.

[jgaryclark]

I scheduled service at local Jayco dealer and they couldn't get me in for a look until May 11...I have 2 trips planned before that. Went to the trailer yesterday and opened up the black tank valve and nothing came out (as expected). It's completely empty. I poured a bucket (10 liters) of water in the toilet to test to see if there was a leak anywhere. I hung around for about 30 minutes and no water was leaking from the undercarriage. Went back today...still no water leaking below. Opened up the black tank valve and 10 liters of (mostly) clean water came out into the bucket. So I'm deducing there isn't a leak in the black tank and there isn't anything clogging the valve.


Must be something between the hose attachment to the trailer and the sprayer to clean the tank...that must be where something is broken to send clean water through the roof vent...right?

[norty1]

OK, I could not pass this up. Thank you Robin Williams!

https://www.youtube.com/watch?v=-lJlEzPzhKc

[jgaryclark]

Funny...but not even close to what happened. Clean water coming out of roof vents, not dirty water.


(Watching that movie was almost enough to scare me away from my purchase last year though!)

[garywilson]

Originally Posted by jgaryclark

Must be something between the hose attachment to the trailer and the sprayer to clean the tank...that must be where something is broken to send clean water through the roof vent...right?

Probably not... the water just looked clean compared to previous dump.

If it went out the vent, the tank was full.

The only reason your floor wasn't flooded was because your toilet seal is good.

For source of water from under, I would guess that the vent pipe leaks somewhere, maybe not glued at a joint or coupling.

My BIL let his flush run for a bit.... toilet seal wasn't too good...he wife kept 'flushing' the toilet trying to get the water to go down...I'm still laughing.

[Bayoutalker]

My tank was overfull once and I saw water dripping from the belly. When I investigated I found that the tank had fallen out of the cheap brackets holding it to the floor and there was a mess on top of the tank. After cleaning it up I re-bent the brackets, reinstalled the tank and added hanger straps across the underside of the tank to keep it from happening again. You should have some play between the belly cover and the bottom of the tank. If you try to push up on the belly and feel it touching the tank you better check that out.

[kblast523]

Originally Posted by jgaryclark

So I'm deducing there isn't a leak in the black tank and there isn't anything clogging the valve.


Must be something between the hose attachment to the trailer and the sprayer to clean the tank...that must be where something is broken to send clean water through the roof vent...right?

There is an anti-back flow breaker that keeps from siphoning black water into the water supply. The first time I attempted to "test" black tank flush, before ever using the tt, with the dump valve closed I got water out of the roof vent...IMMEDIATELY, with only one or two gallons of clear water in the black tank.


My thought is: You attempted to "flush" tank 3/4 full, clean water on top of black tank fill shot up the vent...and the vent has breach which let the water into the area between roof and ceiling. All with dump valve closed.


Second issue: When the tank pressure prevented any more water to enter, the breaker shot water down the wall and filled the bottom cover.


Good Luck.

[jimmoore13]

Since there will be a future dump, I'll share my technique...such as it is.

1. Get a CLEAR FITTING to add to the end of your black tank dump valve...leave it there and cap it when done dumping. This is an important addition to enable you to monitor the dump;
2. Dump the black tank...leave the dump valve open;
3. Using a "dirty" hose...a utility hose...bring the hose inside the bathroom. With the water pump off, open the toilet dump valve and hold it open...be careful with the hose to not damage the flush valve seal. Jet the utility hose down the toilet to dislodge any solids that might be piled up on the floor of the black tank. Flush thoroughly. Close the flush valve. Leave your utility hose inside;
4. Continuing to leave the black tank dump valve open, if your grey tank merges with the black tank dump, dump the grey tank to flush out the stinky slinky. Leave the grey tank dump valve open;
5. Using the utility hose, jet water down the kitchen sink and bathroom sink drains to clear the traps and flush any small particles out of the grey tank;
6. Close the grey tank dump valve, but leave the black tank dump valve open;
7. Now attach your utility hose to the black tank flush fitting. This black tank flush activates a sprayer in the black tank that washes down the walls of the black tank and flushes the residue - tissue, waste solids, etc. - out the black tank dump. LET THIS RUN FOR A LITTLE WHILE UNTIL NO MORE WASTE COMES OUT OF THE TANK AND THE WATER RUNS CLEAR;
8. Turn off the black tank flush, but leave the utility hose attached;
9. Watch that all liquid has drained out of the tank, then close the black tank dump valve;
10. Turn on the black tank flush and add a bit of water...about a gallon or two...to "float the new effluent when you start using the toilet again. This will also slosh in your black tank and continue tank wash-down while you're on the road.
11. Note that the black tank dump valve stays open ALL THE TIME right up to the very end of this process. Closing that valve while adding water to the tank is a recipe for disaster...as you now know.

If you dump at dump stations and there's a line, know that you will need to bring your own utility hose. Most utility hoses provided at dump stations are short, and many don't have an end on that hose...to attach another. A 50' or 100' collapsible hose can be deployed quickly. Bring water pump pliers to swap the supplied hose meant for dump station wash down for your hose. (their hose may be cranked on there very tightly.) Have a helper to help deploy the utility hose and/or operate the garden hose hydrant/hose bib valve. Have "dirty" storage like a flip lid tub to store what you need for this job. Plan your steps and practice, and with practice, you can execute these steps in less than 10 minutes.

Always have high quality nitrile gloves to handle all hoses/stinky slinky, and have a helper who has clean hands to operate doors, etc. Practice removing contaminated gloves in a manner that keeps you from contaminating your hands. Have a place to dispose of the gloves...if one is not provided. Also have a handy supply of hand sanitizer so you don't contaminate your door handles, keys, and steering wheel. Practiced teamwork makes for speed, just like a NASCAR pit stop. Your efficiency will ensure that people in line behind you don't become impatient while you fumble about.

I dump at home using our sewer drain cleanout...and at my previous home, dumping into a port in our septic tank. But I follow all the same steps. I NEVER have issues with my black tank, but there is ALWAYS at least one lump of "something" that wants to block the dump. This is where the hose jetting down the toilet really matters, because you are looking down the toilet drain and can see the water level rising if there's a blockage. I've never had a blockage that actually dammed up the output to the point that the water in the tank wouldn't push it out. The hose down the toilet method is VERY reliable at dislodging and draining out all solids in the tank.

Again, this doesn't help with your OP problem, but this is my way of avoiding such problems from happening and keeping your wastewater systems running smoothly.

[dustyww]

Most municipalities have varying flow rates; Gallons Per Minute (GPM). I’ve seen as low as 8 and as high as 80 for 3/4” line.
Many factors to consider but if it’s your own water, you can easily measure and record it so you know how long to walk away.
I tend to just leave the valve open when flushing the black. My final rinse comes from the toilet down using two five gallon buckets.
Safe travels

[Parrott]

My previous Fleetwood with the toilet on the passenger side(which I will never do again) I installed a hose fitting to the cold side plumbing for the bathroom sink under the cabinet to flush down the toilet to keep the pipe clear from the toilet to the tank. Got tired of dragging a hose through the motorhome. Poor design.

[VKC]

Probably pressured the tank and it was venting so hard it carried water over with it. I’ve done this a couple of times myself. I also had a dirt dobber build a nest in a vent stack and the water would not empty quickly from tanks.