Forgot to open the transition valve with the flush on

[riffgod1000]

Did anyone make the mistake of leaving the dump valve shut with the flush filling the tank?

What kind of damage happened?

Thanks!

[Ray Eklund]

Never used our Black Tank much, but the worst would be if you filled the Black Tank and it forced everything into the interior of the trailer... you would have seen the worst.

If the Black Water did not come up into the Shower... you learned a good lesson without any negative consequences. The shower is the lowest drain in the trailer. The toilet is next.

Sometimes we all find a quarter laying in a parking lot. You found a $5 Bill! Don't let your luck run out after this.

[LilPeanut]

I do it regularly to flush. It fills the tank, I reflush. I set a timer to 5 min. Don’t overfill. Also, sometimes I leave it filling while I open the valve after I have filled it. That works too but I will never do it again with a sewer solution.

Funny story, at Doswell this year, used a sewer solution to pump sewer to the remote dump. Drained the tank, filled part way via the flush then opened the valve but let the flush water keep running like I normally do. But the sewer solution doesn’t drain the tank so it kept filling, but slowly.

Note to self. Don’t do that again.

[mikeinca]

Same here; I flush, refill the tank with the dump valve closed then flush again. Repeat until black tank flush is running clear although usually the second time does it.

No harm is done leaving the dump valve closed while running the tank flush....as long as you don't overfill.

[CBWELL]

If the black tank drain valve is closed and you are filling with the flush valve it will not enter the grey tank and come up through the shower. The only way that the black water can enter the grey tank is by leaving both the black and grey drain valves open and the cap on the outlet. If the black drain valve is closed the water will follow the path of least resistance, up the vent and out on the roof. This will change if the toilet valve is open, or you have a leaky toilet floor flange. Then you have a mess on the floor inside!! Don't ask how I know this!!

[uncle_bob]

Hi

One of the "stock" ways to use the flush system is with the drain valve closed. More or less:

1) Drain the tank as far as it will go.
2) Turn on the flush system and let it go for a minute or so.
3) Shut the drain valve on the black tank (with flush running)
4) Open the valve on the gray tank and let it drain
5) Close the gray valve and open the black
6) Let the flush run until it runs clear or the guy behind you in like really starts to look mad

The idea is that the burst of "clean" water from the flush system will push out a bunch of stuff that otherwise might not go anywhere. Indeed there is some combo of flush pressure and slow gray drain that might cause a black water geyser to erupt from the vent pipe on the trailer. I've never had that happen .... yet ....

Bob

[daleyocum]

On a related note I accidentally blew off the rubber coupler between the outside sewer fitting and the black tank valve inside the belly pan. Airstream fixed it under warranty but otherwise it would have been about $800 to fix.

I did this by using one of the spiffy attachments that allow you to inject water upwards inside the tank to break up clogs. On my second cycle I forgot to open the black tank valve so the water had no where to go. Evidently those little hose clamps can’t put up with 60psi.

These attachments work great for breaking up clogs but in the future I’ll be VERY careful!

[Rltports]

Originally Posted by Ray Eklund

Never used our Black Tank much, but the worst would be if you filled the Black Tank and it forced everything into the interior of the trailer... you would have seen the worst.

If the Black Water did not come up into the Shower... you learned a good lesson without any negative consequences. The shower is the lowest drain in the trailer. The toilet is next.

Sometimes we all find a quarter laying in a parking lot. You found a $5 Bill! Don't let your luck run out after this.

This is confusing to me. How would the Black Tank back up into the shower? My shower dumps into my Gray Tank. Are these tanks connected somehow?

[Howard L.]

Originally Posted by riffgod1000

Did anyone make the mistake of leaving the dump valve shut with the flush filling the tank?

What kind of damage happened?

Thanks!

Yes, I did the very first time we used the trailer. We left the dealership and went to camp with friends. As I arrived and was setting up, everybody came over to help with multiple suggestions. In the confusion that caused, I hooked up the external water to the black tank flush instead of the fresh water connection. (A 2012 30 foot Flying cloud—trailer hookup fittings are above and below each other.). Turned the water on and continued setup of electrical, stabilizers, etc. when I walked into the trailer some 10-15 minutes later, there was water running out of the head and down the floor to the rear bedroom. Thank the Lord, we had not used the toilet and nothing but clear water with little bits of black spray liner from the tanks interior were flowing down the interior floor.
This 30 model has the bath sink also plumbed to the black tank. The toilet will not leak through it’s flapper valve so the tank continues to fill and water finally backs up through the sink plumbing then filling the sink bowl to overflowing.

Obviously I no longer socialize while setting up or taking down. The wife and I checklist and then double check each other..

And finally, yes, I do the flush, dump, fill and flush again, the black tank several times. I time it 3 to 4 minutes per fill.

[Jacob D]

Originally Posted by Rltports

This is confusing to me. How would the Black Tank back up into the shower? My shower dumps into my Gray Tank. Are these tanks connected somehow?

On my vintage rig with no gray tank, the dump valve has side inlets downstream from the dump gate. If the gate is open and the valve outlet is capped (which is how you let gray water into the black tank) the flood can enter the shower when the black tank is full. The same thing could happen if the outlet is capped on rigs with a gray tank if both gray valve and black valves are open.

[Hikingsolo]

Originally Posted by riffgod1000

Did anyone make the mistake of leaving the dump valve shut with the flush filling the tank?

What kind of damage happened?

Thanks!

Two of our airstream park members have done this. The first ran into the toilet and stepped on the toilet pedal causing a geyser flush right into his face. The second one learned a little bit from the first. He went to the blackwater handle and opened it, letting the water drain out. Both had effluent running down the outside of their trailer from the vent pipe and that was how they noticed that there was a problem.

Live and learn! Both gave us all some of the best ever belly laughs ever!

[rmkrum]

Some trailers are plumbed so the bathroom sink drains into the black tank. That’s an interesting hazard, to put it mildly if you leave the black dump valve closed when flushing the tank.

Total attention to the tank dumping task is vital...that’ll be a good takeaway instead of a sudden flood. As they say about plumbers, “it ain’t all water...”

[IrkdScientst]

Originally Posted by riffgod1000

Did anyone make the mistake of leaving the dump valve shut with the flush filling the tank?

What kind of damage happened?

Thanks!

Ummm, yeah, I did that. I had actually hooked up the fresh water hose to the flush input thinking it to be the fresh water input. My bathroom sink drains to the black tank so that's where the water came out. My wife screamed "There's water coming out of the sink! Turn it off! Turn it off!" Fortunately (very fortunately) we had just dewinterized so the black tank was reasonably clean. We caught the flood in time - no lasting damage (or odour).


Lesson learned! I haven't made that mistake again.

[jcanavera]

At least we are warned....if we can read!

[PC Conner]

2018 FC FBQ Manual: "Once the tank is about half full, turn the garden hose off and flush the water from the tank using the dump valve. The valve should be closed during the first couple of minutes, and then opened to let the water out in a rush. Repeat as needed." p. 8-14
Note: "valve should be closed during the first couple of minutes"
Not sure how to follow the directions on the inlet connector to keep the valvue open and the manual's direction to keep it closed during the first couple of minutes.