Correct way to flush black tank

[hikerjohn7]

Originally Posted by Camper_bob

You don't need to change any of the manifold valves; the black flush runs directly from that connection on the side of the coach to a nozzle in the side of the black tank.

Here's what I do:

1) Make sure the tank is at least 2/3 full before dumping. Add fresh water if necessary
2) Dump the black tank
3) Using a dedicated hose, NOT your drinking water hose, run the flush for a few minutes with the black valve open
4) Close the black valve (yes, I know the manual says don't do that) for about 2 minutes (depending on size of tank of course) while the flush fills the black tank some. DO NOT GET DISTRACTED during this step!! If you overfill your black tank with the flush, it will come up through the toilet! SO PAY ATTENTION! You're not trying to fill the black tank all the way up again, you're just trying to get some water in there for another good gravity flush to get all the "heavy bits" off the bottom of the tank.
5) Dump the black tank again
6) Repeat steps 3-5 two or three times to get as much "stuff" out of the tank as possible
7) Turn off the flush, close the black valve, dump gray tank.
8) Put 3-5 gallons in the black tank through the toilet with tank chems

Notice, nowhere in this process did I change the manifold. By design, the waste tanks and assorted plumbing are completely separate from the rest of the water system.

Also, don't do this at a dump station where others are waiting for you. I only do this process at home or if I'm at a full-hookup site.

I leave the blackwater valve closed for a few minutes with the flush-water flowing into the tank also. I figure the escaping gas goes harmlessly out the vent pipe. But I also warm my wife not to open the toilet flush valve.


I wish the tank manufactures would come up with some new ideas for flushing that they could build into RV waste water tank designs. They could add flush water nozzles that spray areas above the sensors, for instance. Or they could build in a rotating spray device like you stick down the toilet to impinge on the walls; but install it inside the tank. It would probably stay functional for years as long as it was used regularly.

[brad104805]

I have the same RV. Just like you say. Connect the water hose to the inlet closer to the rear of RV. Open Black, close grey, turn on the water and let it run for a few minutes. Shut off water, close valve to black. I usually reopen grey then black again as they seem to hold some for some reason. They say don't run water with valve closed - I think because it could overflow the toilet if you forget.

[saarf]

my procedure also!
Note: The separate clean out line connection should have a built in check valve so water does not back up into the source hose.

[bgelyhome]

Originally Posted by Camper_bob

You don't need to change any of the manifold valves; the black flush runs directly from that connection on the side of the coach to a nozzle in the side of the black tank.

Here's what I do:

1) Make sure the tank is at least 2/3 full before dumping. Add fresh water if necessary
2) Dump the black tank
3) Using a dedicated hose, NOT your drinking water hose, run the flush for a few minutes with the black valve open
4) Close the black valve (yes, I know the manual says don't do that) for about 2 minutes (depending on size of tank of course) while the flush fills the black tank some. DO NOT GET DISTRACTED during this step!! If you overfill your black tank with the flush, it will come up through the toilet! SO PAY ATTENTION! You're not trying to fill the black tank all the way up again, you're just trying to get some water in there for another good gravity flush to get all the "heavy bits" off the bottom of the tank.
5) Dump the black tank again
6) Repeat steps 3-5 two or three times to get as much "stuff" out of the tank as possible
7) Turn off the flush, close the black valve, dump gray tank.
8) Put 3-5 gallons in the black tank through the toilet with tank chems

Notice, nowhere in this process did I change the manifold. By design, the waste tanks and assorted plumbing are completely separate from the rest of the water system.

Also, don't do this at a dump station where others are waiting for you. I only do this process at home or if I'm at a full-hookup site.

Same thing I do. In his step 4, I watch the tank level and when it gets to 2/3 I reopen the flush valve. I also have a Valterra 45 degree Hydroflush Reverse Flush Adapter that is clear so I can tell when the Black Tank drain water is clear.

[freespirit2]

Do not forget the handcuffs when filling the black water tank to flush, connect one cuff to the black water dump valve and the other cuff to yourself that way you will not overflow black water into your rig

Wayne

[TWP723]

Originally Posted by freespirit2

Do not forget the handcuffs when filling the black water tank to flush, connect one cuff to the black water dump valve and the other cuff to yourself that way you will not overflow black water into your rig

Wayne

[Camper_bob]

One other user lamented that her husband had gotten distracted yapping with a neighbor once during the flush process and almost (or did, I don't remember) caused a HUGE mess.

She literally made her husband a t-shirt that said something like "WARNING: I am in the process of flushing my waste tanks, please do not distract me!"

[RubyHauler]

I practice the same process for black water flushing with the exception of a different first step.
Number one step for me.... I do a short grey water flush to wet the inside of dump hose to make "stuff" flow easier down the hose. Then after I'm satisfied with clear black water, I finish flush with the grey water.

Have fun and enjoy your Jayco!

[cabinetmaker]

Sorry...couldn’t resist

[Lanie]

I have not used the black flush because it says "fullway termination valve must be in the open position or it may lead to unsanitary conditions" and I do not know where to find the "valve" to see if it is in the open position. Can someone help me with this?

[RubyHauler]

So funny!

[Camper_bob]

Originally Posted by Lanie

I have not used the black flush because it says "fullway termination valve must be in the open position or it may lead to unsanitary conditions" and I do not know where to find the "valve" to see if it is in the open position. Can someone help me with this?

That's just a fancy way to describe the standard knife valve near your waste outlet; the one you pull to empty your tank. You shouldn't let that scare you. If it does, just be sure to leave your black tank open any time you are running the flush.

[Lanie]

Oh my gosh, why can they just say that, lol. We've only camped about 6 times and I just filled the toilet several times to flush. How much easier to hook up an regular hose to do this. Yes too funny!

[Northwestie]

Thank you for asking that question Lanie I was wondering the same thing. I took a wild guess that it meant to have the black valve open. I didn't want to have to look in the owner's manual for my 2017 Greyhawk MVP. That has to be the most unhelpful manual I've ever encountered!

Lisa

[oldmanAZ]

Originally Posted by RubyHauler

I practice the same process for black water flushing with the exception of a different first step.
Number one step for me.... I do a short grey water flush to wet the inside of dump hose to make "stuff" flow easier down the hose. Then after I'm satisfied with clear black water, I finish flush with the grey water.

Have fun and enjoy your Jayco!

I do the same procedure, BUT my initial, short, grey water dump is to ensure all is well with my sewer hose connections!

I don't want a brain fart or bad sewer hose to create a hazmat dump! (And please don't ask how I learned to do it that way. )

[Hollander Mutthaulers]

Good to read all the responses.

Flushing the grey tank last is a great idea! We usually flush black, then grey, then rinse black and rinse dump hose. Makes more sense to let the grey tank water flush the dump hose. The back bumper will probably appreciate it as well. : ) Thanks for the tip!

Tank maintenance and dumping procedures varies depending on whether you are moving often or staying somewhere for some time. After 50 years of primitive tent camping we now have this fantastic mansion - all 16 feet of it - and we still have a tent! Hurray! We usually only stay at a camp for one night, sometimes 2-4 nights, so we're often on the road and have developed a maintenance and dumping practice that works well for us.

To eliminate black tank toilet paper problems we put most TP in an orange newspaper baggie, tie it off, and throw it in the trash. We found POM works well and disintegrates quite readily.

We use a basin in our kitchen sink for food prep and washing and rinsing dishes. That water gets dumped into the toilet when done. It adds more water to the black tank and it keeps spoiled food odors out of the grey tank. The grey tank contains mostly clean kitchen water and personal hygiene water from washing and showering.

After investigating tank additives we decided to use a solution of 2/3 cup Calgon and 1/3 cup Dawn. We keep a number of 8 oz. plastic bottles of solution on hand. 1/4 goes in the sink and the rest in the toilet. It seems to clean and lube the two 25 gallon tanks pretty well although our sensors are iffy at best. We have also used Happy Camper from time to time; it seems to break up solids.

Figuring out what works and sticking to that routine makes camping easy and enjoyable.

[scapel]

I always have water in my black water tank. When we are stopped at a full service RV park, I let the gray drain all the time, but keep at least 1/3 black water.
BTW--I will put the extra ice we have left over if we are headed home and put it in the black water tank so as we travel the ice can slush around and possibly help clean the sensors of any concretions that may have collected.

[cabinetmaker]

Problem solved!

[grantsoo]

Originally Posted by Camper_bob

You don't need to change any of the manifold valves; the black flush runs directly from that connection on the side of the coach to a nozzle in the side of the black tank.

Here's what I do:

1) Make sure the tank is at least 2/3 full before dumping. Add fresh water if necessary
2) Dump the black tank
3) Using a dedicated hose, NOT your drinking water hose, run the flush for a few minutes with the black valve open
4) Close the black valve (yes, I know the manual says don't do that) for about 2 minutes (depending on size of tank of course) while the flush fills the black tank some. DO NOT GET DISTRACTED during this step!! If you overfill your black tank with the flush, it will come up through the toilet! SO PAY ATTENTION! You're not trying to fill the black tank all the way up again, you're just trying to get some water in there for another good gravity flush to get all the "heavy bits" off the bottom of the tank.
5) Dump the black tank again
6) Repeat steps 3-5 two or three times to get as much "stuff" out of the tank as possible
7) Turn off the flush, close the black valve, dump gray tank.
8) Put 3-5 gallons in the black tank through the toilet with tank chems

Notice, nowhere in this process did I change the manifold. By design, the waste tanks and assorted plumbing are completely separate from the rest of the water system.

Also, don't do this at a dump station where others are waiting for you. I only do this process at home or if I'm at a full-hookup site.

I flushed my 26RLS with the black valve open and nearly had disaster!!
It was not draining but did let go just as it backed up into the toilet.
Fortunately I only had a small spill in my brand new (1st trip) trailer.
I must have had a TOILET PAPER PLUG in the tank outlet!
That is the only thing I can think of even though I always used RV paper. Maybe some manufacturing debris?
I saw afterward you can get transparent connectors just to make sure that what goes in is coming out.
So NEVER get distracted when flushing. Always make sure you have flow out.

[Auto_Pilot]

This is how we have flushed our black water tank for the past three years and it works well. We we are on a full service site we tame the time to flush the tank well! My wife stays inside and watches the black water gauge. I dump the black water then hook up the flush hose. Then run it with the valve open for a good 5 minutes. Then I close the valve and let it fill up. The second d the gauge says full I dump it. Our level gauge has worked the very best since we started flushing this way! As a few people have said PAY ATTENTION or sh**y things can happen!