Black Tank Flush with Drain Closed? Problems?

[fez111]

Yes, that's exactly what the warning is for.

You hook it up and start putting the water in, then your neighbor comes over and starts chatting, you have a good talk and next thing you know, the black tank water is coming out of the vent on the roof.

Hasn't happened to me, but I have seen it happen....

Our friends at our park in Florida admitted to once showering the park with sewage from his roof vent when he got side-tracked while flushing....

[finz04]

I did not read every page of this thread, sorry if I'm repeating what's been said already.

I think there could be a better name than "black tank flush". My experience with my Reflection and past trailers is that it certainly doesn't "flush" anything. That little whirlybird gizmo probably sprays water around the inside of the tank, but flush... I think not likely.

Having said that I do find it to be very useful for introducing water into the tank. I find the best "flush" is to close the gate and let the tank fill to somewhere between 1/2 and 3/4 (by guess, no science) and then open the gate. That sudden swoosh of water when you open the gate with a sufficient amount of water in the tank is the best "flush". Do that 2 or 3 times and it will clean out the tank better than the "tank flush" by itself. That little feature is useful for introducing water into the tank on a controlled basis, but that's about it.

I don't worry about overfilling during my process, because it's kind of dedicated time for me. I don't walk away and let it run. I stand by. If any thing came back up out of the toilet, I'd be divorced.

[phuber9458]

This is what I do as well. I set it for 3 minutes. I sometimes worry if water pressure is high whether I'm going to overflow... one of these days I will test with high pressure how long it takes to fill a 5 gallon bucket.... For those that do this with the gate closed, how long do you usually fill for ?

2 minutes. I have a 42 gal tank

[Texdan]

Yes, that's exactly what the warning is for.

You hook it up and start putting the water in, then your neighbor comes over and starts chatting, you have a good talk and next thing you know, the black tank water is coming out of the vent on the roof.

Hasn't happened to me, but I have seen it happen....

Ha. My wife was using the bath sink to rinse out a shirt. I was outside and she came out. Neighbor came over and they got to chatting. In a little while I saw water flowing into the front storage and didn't know what my wife had been doing inside. Luckily was just the sink and not the black tank!

[mbergthold]

We dump at home immediately after arriving, easy to avoid distractions. I do an initial dump, close the valve & add water thru the cleanout, dump, and repeat until clean.

[Schiefswret]

Personally I don’t use the spray connection only because I’m already hooked up to the black flush so why make an extra step? Upon finishing the flush I close the valve and let the water run to the 5 gallon point then turn it off. I bought a water meter that attaches to the hose at local home store and it tells me exactly how many gallons have passed through. I think it was about 15 bucks. Hope that helps. Travel safely.

[bertschb]

For those that do this with the gate closed, how long do you usually fill for ?

I have a water flow meter. I'm not sure how accurate it is but I usually add about 10 gallons before dumping it. Surprisingly, it takes quite a while to get 10 gallons at 55psi water pressure with my hose/fittings, etc. Maybe 6-8 minutes? Just guessing. I do this flush 2 or 3 times each time I empty the black tank.

If it didn't take so long to add the water, I'd probably add 20 gallons before dumping it.