Black Water Tank Flushing

[DirtyMax88]

Hey everyone! We went to flush our black tanks yesterday on our LM Newport after our trip. Hooked everything up, and turned on my garden hose, and no water was going into the tanks. Disconnected, read the directions it gives you on the inside of the door (pictured below) on how to hook up and flush, and still had no water being pumped into the tank. Am I missing something here. Is there a special valve somewhere I need to open so water will flow to the black tanks? The valve that you rotate around for city water, filling your fresh tank, etc, has a sanitize/winterize option, am i supposed to rotate to that position (pictured below)? Seems that since that's a different connection, they two aren't related. A warming label next to the black water flush hose connections reads "do not use tank flush valves unless the fullway termination valve is on the open position." Where is this fullway termination valve? From what I have read and heard, this is a pretty simple process, correct? And I should be able to hear the water being sprayed inside the blank tanks as well? There has to be something simple I am missing. Thanks!

 

[RoadJunkie]

The warning is designed to ensure the dump hose is terminated into a sewer connection and the black water valve is open prior to adding flush water into the holding tank. Otherwise, the tank would back flow water into the coach via the toilet when the holding tank became full. No other valves are in play during this process. The flush water is sprayed into the tank and does not make a great deal of noise; I have to listen very carefully to hear mine. I use a clear section on the sewer hose to monitor all aspects of dumping the RV tanks. When I flush the tank I can observe the flow and color of the contents to determine when the flush is complete. I don't rely on just hearing when flushing. Also, never, never, leave the flush process unattended! You won't like the results.

 

[danemayer]

The 2 water hose connections under the 4-way valve are where you hook up the hose to flush each of the black tanks. The appropriate black tank gate valve (two Waste Water Holding Tank handles at the bottom of the UDC) has to be open when you're flushing each tank or you will overfill the tank and create a huge mess.

 

[DirtyMax88]

Thanks Dan,
Good deal, That is exactly where I had the hose hooked up. I had both black tank valves open when I was doing this process. I may have been doing it correctly, and just not heard or seen the dirty water come out. Maybe it takes some time, We have septic at our house so i had the sewer hose connected, but loose enough to see if anything came out. I just assumed that with the amount of water going into the tank to flush, a ton would be coming out, and that wasn't the case. Also, I left the hose water on when I disconnected and it seemed almost like the flush outlet was clogged or something, because a decent amount of water came out through it. It just seems like this is a super simple process, and there really isnt much that can go wrong, if done correctly. Also, I have seen or heard of people closing there black tank valves and letting the flush water fill up inside to help with cleaning as well. Only thing with that is im guessin you really need to pay attention to your tank gauges, so you don't over fill it huh.

- - - Updated - - -

Thanks RoadJunkie,
Maybe everything was working and i just couldnt hear it. I'm not sure, as i stated in my reply to Dan, I'm not exactly sure what i was doing wrong, or if just didnt give the system enough time, but i didnt see any water (dirty or clean) comeing out of the sewer hose. It worried me that since i had everything hooked up and the hose on, that the water was going somewhere, and it wasn't coming out the sewer hose. Maybe i can give it another shot when i get home this evening. Like i was telling Dan, we are fortunate (or unfortunate depending on how you look at it) that we are on septic, so i can just attach my sewer hose to the cleanout on the septic tank. I am have a clear elbow on order as well! If all else fails, i can do it the old fashioned way, from inside the bathrooms.

 

[danemayer]

You may find our owner-written Water Systems Guide useful. Pages 17-21 address dumping the tanks, and useful accessories as well as a discussion on how to clear blockages and how to avoid them.

It's not unusual to open the dump valve and get a quick rush of outflow, and then almost nothing. This happens if a big wad of solids block the tank outlet. If adding water through the tank flush, you need to be very careful at this point because you can overfill the tank pretty quickly.

With a clear twist-on adapter, you can monitor what's coming out and take appropriate action, back flushing if necessary to clear the blockage.

The user guide should make this all clear.

While you're looking at the user guide, download the Residential Refrigerator Guide. You'll need to follow the winterizing procedure when temps drop this Fall, even if you're living in the coach.

 

[RoadJunkie]

We also work as a team where my bride fills and flushes the bowl about a dozen times. In my opinion, this is the key to getting everything moving. When you get your clear piece you will observe what I'm talking about. I always wondered how many people dump until the initial surge is complete and fail to recognize the importance of waiting for the rest of the story. Sometimes there is significant blockage that is moved by the full flush process. Good luck.

 

[Bob&Patty]

If you do not have one...get the clear adapter. I usually takes 3-4 times of flushing to get "black tanks" clean. You also should put in about 5 gallons of water and leave it in the tank. We use Calgone and a little Dawn dish soap after the flush. It keeps the tank from smelling and things loose. I also time the fill ups to 5 minutes each time. Never walk away while flushing. Don't ask. Most people install a Volterra gate valve on all the dump pipe ends and leave them there. A Black tank valve stuck open can wash your shoes and socks when you remove the cap. DON"T ASK.

 

[DirtyMax88]

Thanks everyone.

Yesterday evening I attempted to do the flush again. One of my flush connections has to be defective or plugged or bad, something. When I hooked to the second one, it worked perfectly. So I had to flush the other tank the old fashioned way (no biggy, just took a little more time). Everything is nice and clean and fresh now. With the suggestionsfrom the other posts, I filled the tanks with about 5 gallons of water, added chems, as well as some dish soap and we are ready for the next trip. Now to try and figure out whats with that hose/flush connection. I was thinking of taking that flush connection off, Swap the working one, and that at least can eliminate the flush valve connection. Other then that im not sure why its not working correctly.

 

[jmgratz]

One other suggestion I haven't seen is to be sure to not leave your tank completely empty when storing between your trips as anything that my be left in the tank will harden and never be removed. We always leave a couple of gallons in the tank even in the winter. (that small of amount would not damage the tank if it froze IMHO.

 

[danemayer]

Thanks everyone.

Yesterday evening I attempted to do the flush again. One of my flush connections has to be defective or plugged or bad, something. When I hooked to the second one, it worked perfectly. So I had to flush the other tank the old fashioned way (no biggy, just took a little more time). Everything is nice and clean and fresh now. With the suggestionsfrom the other posts, I filled the tanks with about 5 gallons of water, added chems, as well as some dish soap and we are ready for the next trip. Now to try and figure out whats with that hose/flush connection. I was thinking of taking that flush connection off, Swap the working one, and that at least can eliminate the flush valve connection. Other then that im not sure why its not working correctly.

There's a vacuum breaker/check valve on the main bathroom flush line, and I assume the 1/2 bath also has one. It's conceivable that the valve could either be defective or possibly was installed backwards. For the main bath, it's usually behind the shower wall, next to the faucets. You probably have an access panel that will let you inspect it.

If the flush problem is with the 1/2 bath, you may have to look for an access panel or call Heartland Customer Service at 877-262-8032 / 574-262-8030. Have your VIN # ready. If you find it, please let us know where it is in case someone else needs to check theirs.

 

[DirtyMax88]

One other suggestion I haven't seen is to be sure to not leave your tank completely empty when storing between your trips as anything that my be left in the tank will harden and never be removed. We always leave a couple of gallons in the tank even in the winter. (that small of amount would not damage the tank if it froze IMHO.

I was talking to a friend of mine who suggested that too! Thank you Jim!

- - - Updated - - -

There's a vacuum breaker/check valve on the main bathroom flush line, and I assume the 1/2 bath also has one. It's conceivable that the valve could either be defective or possibly was installed backwards. For the main bath, it's usually behind the shower wall, next to the faucets. You probably have an access panel that will let you inspect it.

If the flush problem is with the 1/2 bath, you may have to look for an access panel or call Heartland Customer Service at 877-262-8032 / 574-262-8030. Have your VIN # ready. If you find it, please let us know where it is in case someone else needs to check theirs.

Thank you Dan! I will see what I can find when i get home today! If and when i find it, i will be sure to let you know, hopefully even get a picture or two!

 

[wdk450]

Be aware that the plastic vacuum breaker will blow apart under high water pressure conditions, and cause a water mess in your trailer. It happened to me in Wells, Nevada.

 

[cemill]

We just purchased a new 2015 3650 Big Country and have the very same problem.
When connecting a water hose to the black tank flush it acts as if there is a valve closed
or a check valve stuck or installed backwards.
Does anyone know where the check valve is located?

 

[Bob&Patty]

cemill, see post #10 on this thread.

A great point by Bill, never ever use the tank flush without a pressure regulator. Don't ask.

 

[JohnD]

I'm new to the black tank flush system as well, but have now used it twice, and so far it has been great!

I used to have to use a wand down the toilet to clean out the black tank (still have the wand as back-up), but the black tank flush sure seems to save a lot of time and work!

One thing I've noticed (not sure if this is true) . . . but when I have the water running in the flush, it seems that the tank level indicators don't work as water is running over the sensors!

Anyone have an opinion or experience on this?

 

[Bob&Patty]

No John, I never noticed that. But I never leave the outside to go inside the look at the monitor.

 

[danemayer]

I'm new to the black tank flush system as well, but have now used it twice, and so far it has been great!

I used to have to use a wand down the toilet to clean out the black tank (still have the wand as back-up), but the black tank flush sure seems to save a lot of time and work!

One thing I've noticed (not sure if this is true) . . . but when I have the water running in the flush, it seems that the tank level indicators don't work as water is running over the sensors!

Anyone have an opinion or experience on this?

The tank sensors pass a low voltage signal when wet. The minerals in the water conduct electricity. So if you're spraying inside the tank, there's a good chance the sensors will be wet and send a signal to the control panel. TP or other solids on the sensors will also conduct electricity even when the water level is lower than the sensor(s). The crud that builds up in gray tanks is probably also responsible for creating false sensor readouts.

 

[Gapboat239]

Just went to flush the tanks on our new BC 3950 FB (1-1/2 bath), same issue. DirtyMax 88, did you get your issue resolved? It is just like the the line is plugged, no water getting to the tanks.