More newbie questions - black tank flush system

We just started our TT life in the fall with the purchase of our first one.
I have read up a lot on the care and feeding of this new "animal", but am finding some minor issues in spite of all my attempted preparedness.

Today's adventure: using the black tank flusher for the first time.
I knew we had some solids piled up in the tank that need to get out of there, so I got situated to dump at home and connected the water hose to the outside and turned it on. I ran the flusher and watched the tank level come up past 2/3's before I went outside and pulled the handle to open the vale and drain. It seemed like very little of the solids came through. So I turned on the water and let it fill till it read full this time. Draining seemed like all liquid again.
Round 3: Filled to full and looked down through the toilet to see that it really was nowhere near full even though the indicator said it was. Turned the water back on while monitoring through the toilet and filled until the liquid level was just bellow the bottom of opening into the tank. I could see a lot more moving around inside the tank this time, but it still left a lot of solids laying in there when I drained it.

The first thing I realized during this process is that the flusher system sounds great in theory, but there is no outside way to monitor the level in the tank to know when you need to shut off the water / or open the drain. Maybe this doesn't matter if you are dealing with routine dumping, but for my situation of trying the loosen up stuck solids, it's a pain running in and out around teh TT to turn on and off the water. This leads to a change I'd like to make. I'm thinking of putting a valve for the flusher on / off inside under the bathroom sink so you don't need to run outside to shut it off.

Then I stepped back inside the TT again and realized I now had a sizable puddle of water growing across the bathroom floor. I quickly traced it back to the flusher system water line. There is some sort of check valve / vacuum breaker valve under the sink. It appears that water pressure is supposed to seal it shut and then let air in when you stop flushing to let the line drain. I leaks about on drop per second while the water pressure is on. It does not look like an item you can repair so, something to get replaced to fix the leak.

At the moment, I have filled the black tank completely, and am letting it sit to soak / loosen up solids overnight. I will see how much better it drains out tomorrow morning. If it does not clear out much better, then I am thinking I may need to go get one of the through the toilet wand type washers at this point.

Any advice is appreciated!

28 Replies

Bumpyroad
Explorer
Apr 15, 2014
Heavy Metal Doctor wrote:

HMMMMMM......thanks for that link! Me and the RV dealer and possibly Keystone are gonna have a chat about this one......the way that info is written, that valve needs to be outside the TT somewhere - not under the bathroom sink where it will leak and put a puddle on the floor (like it did for me).

And just looking at the parts involved I had already considered that this valve could vent some stink out of the black tank if it does not seal tightly on the connection to that half of the circuit.

from the picture of such a device in that other thread I referenced it looks to me like my first "mod" would be to eliminate that vent at the top and just use an anti backflow device on the feeding hose, outside of the RV.
bumpy
Heavy_Metal_Doc
Explorer
Apr 15, 2014
Lynnmor wrote:

The valve will expel water, see page 11.

PDF

HMMMMMM......thanks for that link! Me and the RV dealer and possibly Keystone are gonna have a chat about this one......the way that info is written, that valve needs to be outside the TT somewhere - not under the bathroom sink where it will leak and put a puddle on the floor (like it did for me).

And just looking at the parts involved I had already considered that this valve could vent some stink out of the black tank if it does not seal tightly on the connection to that half of the circuit.
Bumpyroad
Explorer
Apr 15, 2014
Lynnmor wrote:
Bumpyroad wrote:
Heavy Metal Doctor wrote:

Not connected to the sink system in any way, that is just where they mounted the the antiflow valve. The outside connection is on that wall and runs inside the cabinet bellow the bathroom sink, then to this valve, and on down through the floor to the black tank.

So, you're saying I should be prepared for this valve to drip a little each time you shut it off? I know mine is messed up because it drips all the time when the water it is on.

that doesn't make any sense to me. perhaps somebody with the same RV can add something here. every screw on the hose end anti backflow valves that I have used do squirt out water when the water is shut off. wouldn't think they would put such a valve inside a RV however.
bumpy

The valve will expel water, see page 11.

PDF

interesting, thanks, I still don't see how that is an "improvement" to the old way. I'd still use another anti backflow device on the feed hose.
bumpy
Monaco_Montclai
Explorer
Apr 15, 2014
the idiot lites are just that,i knew that waz comeing here too.so startyed watching how much waz going it the tanks incase the lites were wrong.so tried the cem called I----c----e--. only if we were leaveing from this stop to the next, and in the warmer temps.works great. the idiot lites aint much good. I guess the technology aint there yet.the ice works great, and don't hurt a thing. now its all happy-camping
Lynnmor
Explorer II
Apr 15, 2014
Bumpyroad wrote:
Heavy Metal Doctor wrote:

Not connected to the sink system in any way, that is just where they mounted the the antiflow valve. The outside connection is on that wall and runs inside the cabinet bellow the bathroom sink, then to this valve, and on down through the floor to the black tank.

So, you're saying I should be prepared for this valve to drip a little each time you shut it off? I know mine is messed up because it drips all the time when the water it is on.

that doesn't make any sense to me. perhaps somebody with the same RV can add something here. every screw on the hose end anti backflow valves that I have used do squirt out water when the water is shut off. wouldn't think they would put such a valve inside a RV however.
bumpy

The valve will expel water, see page 11.

PDF
Bumpyroad
Explorer
Apr 15, 2014
thanks, just saw a picture of one at "WOW! What a stench - almost gassed us out! "
seems like a poor design to me, dripping water on the inside of the RV?
I mean some folks have expressed concern about hooking a 30 ft hose to a flusher or sewer solution and getting feed back into the potable water and this seems to me to be a lot riskier?
bumpy
Huntindog
Explorer
Apr 13, 2014
Bumpyroad wrote:
your flusher system is somehow connected to the sink inside the RV? a very strange hookup. and the antiflow valve will leak when shut off as a little water will drain back from the "clean" side.
and if you want to blast at the pile of stuff, do not build up a bunch of water in there when you try that. all that extra water will do is absorb some of the hydraulic shock that the sprayer is trying to give the stuff.

since you bought the RV last fall and only now are using the sprayer for the first time, it may be impossible to get that pyramid out without heroic measures. as a last resort you could use a pressure washer either down thru the toilet if possible or remove the black tank sprayer and poke it in that hole.

and the salesmans statement I guess I will get the toilet wand and the Johnny Chock (Thanks to the poster who put that up! I would not have thought of it.) and be prepared to use that since this installed flusher is not good for this situation, in spite the sales guys promises that "You'll never need anything else!" would probably be true if you would routinely use that sprayer, not once a year after it becomes too late.
bumpy
This is a normal setup nowadays. The water hose screws into a fitting on the outside of the TT. It usually goes up to a location under the sink, or behind the shower etc. It connects to a air gap antisiphon valve. The output from this valve now heads down to the tank sprayer. It shouldn't leak much when shut off, as gravity will make the clean side drain down thru the hose connection outside the TT. Maybe a drop or two.

This is to prevent the possibility of black water entering the freshwater supply..
Everyone should be using some sort of device to prevent this. It is probably code in most locations, and even if it's not, your neighbors will appreciate it's use.
Bumpyroad
Explorer
Apr 13, 2014
Heavy Metal Doctor wrote:

Not connected to the sink system in any way, that is just where they mounted the the antiflow valve. The outside connection is on that wall and runs inside the cabinet bellow the bathroom sink, then to this valve, and on down through the floor to the black tank.

So, you're saying I should be prepared for this valve to drip a little each time you shut it off? I know mine is messed up because it drips all the time when the water it is on.

that doesn't make any sense to me. perhaps somebody with the same RV can add something here. every screw on the hose end anti backflow valves that I have used do squirt out water when the water is shut off. wouldn't think they would put such a valve inside a RV however.
bumpy
wmoses
Explorer
Apr 13, 2014
Heavy Metal Doctor wrote:
I guess I will get the toilet wand and the Johnny Chock (Thanks to the poster who put that up! I would not have thought of it.) and be prepared to use that since this installed flusher is not good for this situation, in spite the sales guys promises that "You'll never need anything else!"

You are welcome.

The Johnny Chock is one of the best gadgets out there for thios sort of thing and should be standard kit for any RVer, IMO. It was very useful with my previous RV which had no flusher system and I had to use the Johnny Chock periodically when I wanted to give the RV a good cleanout.
mooky_stinks
Explorer
Apr 13, 2014
Do you live where there are freezing temps? If the tank sprayer connection wasn't winterized, the anti-flow valve could be cracked from water left in it.