Winterizing the Black Water Tank

[Art_Davis]

When you winterize, what do you do to the black water tank? I usually drain, put a bit of water in, and add some antifreeze--with some antifreeze in the toilet bowl.

I assume I shouldn't store it dry. Right?

[Art_Davis]

Sounds like mixed opinions! I have always put a bit of antifreeze in the toilet bowl, too, to keep the seal lubricated--even during the summer. I just pulled the rig out of the garage to ready it for a trip, though, and found that it had dried up! What gives? I've always seen this recommended!

[MFL]

My FW does not get used from Nov. to May. I don't like leaving the black tank dry anytime, even in winter.

I do flush it out better for winter storage, and then add a couple gallons of the cheaper RV antifreeze. I like to have some liquid in there, and the other thing is, the antifreeze seems to keep the valve seals lubed, better than water or "air". JMO

I pour extra antifreeze down the drains for the two gray tanks as well, to help lube their valve seals.

I do leave the fresh water tank dry, for winter storage. I sanitize it spring time, and usually keep a little city water in it, between outings, until winter again.

Just my way,
Jerry

[Cummins12V98]

beemerphile1 wrote:
Store empty, air won't freeze.

ZACTLY

[rondeb]

I completely clean the black tank with a wand so it is spotless. Drain all tanks. Then winterize with the pink stuff. All tanks are stored dry. Pink stuff is in the traps and about a qt in the toilet bowl. We only use a little water in our fresh water tank while we are moving and as soon as we are stopped for longer than a few days we drain it. Most of the time our Fresh Water tank is dry. I have always figured that any water sitting for any length of time will grow "something" so when stored all tanks are cleaned and dry. We leave the outlets open to the fresh, gray and black and use a screen to make sure nothing crawls in. Who knows if it is the right way or not. There are sure a lot of different ideas after reading this.

Just winterized 2 days ago

[Dick_B]

I dump a gallon or so of the pink stuff into the tank over the winter. I'd be cautious of storing it `dry' unless you are absolutely sure the tank is clean; hard to do with a Black Tank.

[jk31668]

for the black tank, sink and shower drains/traps i use the blue cheap windshield washer antifreeze. it only around $1.99 a gal vs the pink stuff.

[frankdamp]

If the black tank has any "black" water in it, it will have a lower freezing point than clean water anyway. If the tank is more or less empty there's lots of room for it to expand if it does ice over.

Don't waste the anti-freeze!

[beemerphile1]

Store empty, air won't freeze.

[downtheroad]

....and I blow compressed air through our black tank flush to clear the water from it also.

[LynnandCarol]

Always stored dry for the winter (all tanks). Put RV anti freeze in the all the lines and toilet (don't forget outside shower if have one). we now just move the trailer south!

[n7bsn]

I make certain there is antifreeze in the inlet valve to the toliet.
But as long as the the tank is empty, it shouldn't matter. Recall the issue is water expands, a (nearly) empty tank has lots of room for the waste water to expand

[gbopp]

I drain the black tank. I don't put any water in because you probably can't get all the water out, there will be some left.
Add Antifreeze to the tank and toilet.
Sounds like you got it right.

[empty_nest]

That's exactly what I do.