Winterize my black tank??

jhudson13 · 11-12-2019, 09:53 AM

We picked up our new TT a month ago, camped 1 night on the way back home and then the next day we removed the factory toilet and installed a composting toilet. So the black tank has only been used that 1 time and will probably never be used again. Any precautions you think we should take?

007matman · 11-12-2019, 09:58 AM

Quote:

Originally Posted by jhudson13

We picked up our new TT a month ago, camped 1 night on the way back home and then the next day we removed the factory toilet and installed a composting toilet. So the black tank has only been used that 1 time and will probably never be used again. Any precautions you think we should take?

If you are not going to be using it and you flushed/drained it well then you're good. The rest of your water system still needs winterized.

Jax Wylde · 11-12-2019, 10:24 AM

As a follow-on to what 007matman posted (which I agree with)...are you considering using your Black Tank as second Grey Tank?
This is something that many people, that have added composting toilets, have done.
The easiest way to do this is by using a Twist-on gate valve (such as the Valterra T58). It's cheap (<$20), and enables you to combine the two tanks to increase Grey water storage.

There are many YT videos showing how it's done, and what to keep in mind if you do this. Search 'combining black and grey tanks'.

cheers.

jhudson13 · 11-12-2019, 10:26 AM

No I had not but will 100% be looking into this. Thanks for the idea.

5picker · 11-12-2019, 10:29 AM

Quote:

Originally Posted by jhudson13

We picked up our new TT a month ago, camped 1 night on the way back home and then the next day we removed the factory toilet and installed a composting toilet. So the black tank has only been used that 1 time and will probably never be used again. Any precautions you think we should take?

Did you empty the black tank after the one use?
If so, there isn't anything much to do.

If you didn't (and I don't know what went in the tank nor care to) but if there IS anything in there, you really should get rid of it.

Since you now don't have a way to put anything in the black tank via the toilet, all you can do is drain to the best of gravity's ability.

If you have a black tank flush, hook up and flush, drain and close the drain valve and then push some (maybe a couple cups) of R/V antifreeze through the black tank flush and leave it in the tank.

Combining the black and grey tanks is an excellent idea!

Jax Wylde · 11-12-2019, 10:59 AM

Quote:

Originally Posted by jhudson13

No I had not but will 100% be looking into this. Thanks for the idea.

No problem. One thing I forgot to mention, in my earlier post, is that this will only work if you have a single outlet for both grey and black tanks. If you have separate 3" outlets (i.e. one for the grey, one for the black...as some TT's do), this solution alone won't work.

For those situations, there are other ways (such as using a 'Y' connector + waste hoses) to combine both tanks along with using the twist-on gate valve. But that is not as elegant a solution as having a single outlet for both grey/black.

DrLewie · 11-12-2019, 02:19 PM

It can't do any harm to put some RV antifreeze in the waste tanks. If you are winterizing with RV antifreeze and not just a blow-out, some of the antifreeze will get into the tanks when you pump water into the system. Just remember to flush the toilet after you see pink. I'm very conservative when it comes to simple and cheap maintenance options. I figure a few bucks or a few minutes of prevention can save a big headache down the road.

jimmoore13 · 11-12-2019, 03:56 PM

I'll join the chorus of those recommending adding RV antifreeze to the black and grey tanks for the winter.

No amount of draining gets all the water, and it's likely that water will still be in the vicinity of the dump valves...the most exposed spot in those systems.
A quart or two of RV antifreeze will settle up against the dump valves and protect them from freezing and from drying out.

I winterize my freshwater side of my PUP with air. Then I pour RV antifreeze down all sink drains to protect the traps and the dump valves. The grey tank side consumes about a gallon, because I have two traps to protect...one of which hangs below the camper body...and then I need to get enough into the grey tank to deal with dilution by water in the traps.

Alternatively, I could leave the grey tank dump open and watch for RV antifreeze to replace water, but with two separate traps to deal with, I just pour enough antifreeze down the grey drains to ensure that the tiny amount of water in the traps can't dilute the antifreeze enough to cause issues.

When you store your factory toilet, take steps to protect the flush shutter seal, or it may dry out and require replacement if you ever go back to the factory toilet...say when you trade in. As desirable as your mod may be to you, it is likely to devalue your coach on trade in.

Delco Bobby · 11-12-2019, 05:36 PM

Is there any chance that the bathroom sink drains into the black tank?

5picker · 11-12-2019, 06:27 PM

Quote:

Originally Posted by Delco Bobby

Is there any chance that the bathroom sink drains into the black tank?

We've certainly have had reports of the shower draining into the black tank in some models so there would be a possibility the sink could too.

With an empty black tank and the drain valve open, run water in the bathroom sink and see if it runs out the drain.

Larry-NC · 11-12-2019, 08:10 PM

Quote:

Originally Posted by jimmoore13

I'll join the chorus of those recommending adding RV antifreeze to the black and grey tanks for the winter.

[COLOR="Red"]No amount of draining gets all the water, and it's likely that water will still be in the vicinity of the dump valves...the most exposed spot in those systems.

Absolutely. I can testify to that. The HDPE tank is somewhat flexible, and also flares outward going up from the bottom (like an ice cube tray). The tank won't be hurt.

However, the tank drains downward in delicate ABS pipe to the drain valve. Any water will collect there, freeze, and crack the pipe or elbows. (The valve itself has so little contact with the freezing water that it won't break.)

The safest and easiest way to deal with this is to simply leave the drain valves open during freezing weather. We (and our neighbors) usually just connect the tote to the trailer and leave the valves open all winter. Any water we do flow into the gray water (e.g., rinsing dishes or brushing teeth with bottled water, dehumidifier) goes into the tough HDPE tote which also flares from the bottom.

jkoenig24 · 11-13-2019, 10:02 AM

"camped 1 night on the way back home"

If ANYTHING was put into the toilet during that trip home, it NEEDS TO BE DRAINED & WINTERIZED. There also really NO way to be sure that somebody had "used" said toilet before you took delivery. I'd add ~ 32oz of RV Antifreeze, drain it and then add and leave another ~ 32oz in the black tank along with ~ 8oz in the bowl (for a "drop" toilet). Simple and inexpensive; could save you a LOT of grief later.

Semperfi24 · 11-13-2019, 10:22 AM

I can confirm that on our Rockwood Mini Lite 2504S, the bathroom sink drains into the black tank. So it is definitely possible. I'd guess it isnt the only model that has done this

Jay2504 · 11-13-2019, 10:57 AM

X2 on Rockwood 2504s bathroom sink drains into black tank. Jay

DrLewie · 11-13-2019, 03:52 PM

My Cardinal bathroom sink drained into the black tank (I found out the hard way). The shower seemed to be connected to the grey, but I'm not certain. That model year had one black and 1 grey tank. I'm in a non-FR trailer now and it has 2 grey tanks...one for the kitchen sink and one for the basin and shower. A much better arrangement.

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