Holding tanks in cold weather

[bedell]

Should grey and black tanks be completely drained for the winter or do you leave some liquids in them? I have read that the black tank especially should not be allowed to sit totally dry for for long periods of time. How serious would it be if there was some freezing in those tanks?

[Uplander]

Agree with it all with the exception of the hot water tank...that I just drain and forget it (it is on a by-pass system and no antifreeze is required or needed once it is drained).

[pdmac1946]

The pink stuff in the holding tanks helps to keep the gate seals lubed. I like it in my whole system. Pipes and waste holding tanks. I also run a little in my drained
hot water tank. I flushes out easily.

[Coalminer_UG]

Just a note. All the pink stuff will freeze at certain temps. The good thing is the stuff does NOT expand and break lines etc. Only stuff to use in your rv.

[time2roll]

BillyW wrote:

EYEMAN3561 wrote:
Is it best to have PG antifreeze left standing in the toilet for the sake of the seal?

I always do. I can't see how it could be harmful, but it's easy to imagine the seal being ruined by drying out.

I need to start doing this.


For the OP I recommend drain the tanks completely and split a gallon between the tanks, traps and toilet.

[TurnThePage]

EYEMAN3561 wrote:
Is it best to have PG antifreeze left standing in the toilet for the sake of the seal?

I always do. I can't see how it could be harmful, but it's easy to imagine the seal being ruined by drying out.

[beemerphile1]

Drain and leave dry, air won't freeze. If the tank is reasonably clean, drying won't harm a thing. If you leave a pile of waste in there it could be a problem, so don't.

[EYEMAN3561]

Is it best to have PG antifreeze left standing in the toilet for the sake of the seal?

[myredracer]

brownieab wrote:
Use the pink stuff, the drain valves need to stay wet or the seals will leak later

But be aware that there are two types of "pink stuff". One is alcohol based and one is propylene glycol based. The ethanol stuff can cause damage to seals and a bad taste and odor in your lines when you de-winterize and should only be used with PEX and Quest piping. The PG type will do the opposite of the ethanol version - it will help to extend the life of seals.

The PG type can apparently be re-cycled stuff though (see article) so be wary of what you buy. Walmart supposedly carries the virgin stuff (I haven't checked). Look for "virgin" on the label such as this Starbrite brand. I think Prestone also makes it.

The ethanol type is cheaper which may entice you to buy it. I saw some anti-freeze at Home Depot yesterday for a good price and thought I would buy some until I saw that it has ethanol.

http://www.rvlife.com/columns/tech-tips/4015-techtipsrv-antifreeze-not-all-the-same.html

http://mainecamperdealer.com/what-you-need-to-know-about-rv-anti-freeze/

FWIW, the pink stuff is available in a -100F burst temp. rating rather than -50F. I read reports of some owners having damage to their piping from the brutally cold and long last winter so getting the lower rating might be extra insurance.

[TurnThePage]

dadmomh wrote:
BWT....just a question.....doesn't the blue car window washer stuff freeze?? Otherwise, why do they sell Winter Anti Freeze and sometimes the blue stuff in my car won't work until the engine warms the area. Just wondering.

I haven't seen it freeze in the tank, but it does on the windshield for sure. If it froze in the tank and expanded like water, I think we'd hear a lot more about it.

[dadmomh]

Use the pink stuff that is intended for this purpose vs something modified that may or may not be such a great idea. You'll be in for about $10 for 3 gallons and that should be more than enough. When you add the pink stuff to the toilet and flush once, you'll have liquid in the black tank then, so any residue on the bottom won't completely dry out. Some folks swear they can do the job with 1 gallon....we usually overkill with 2 1/2 - 3 gallons, but we're darned sure it's protected.

BWT....just a question.....doesn't the blue car window washer stuff freeze?? Otherwise, why do they sell Winter Anti Freeze and sometimes the blue stuff in my car won't work until the engine warms the area. Just wondering.

[legolas]

MitchF150 wrote:
I"m pretty sure JK was just talking about putting the windshield fluid in the holding tanks ONLY.. 😉

Mitch

First, folks need to know what they are doing/talking about before they give advice, Second, they need to be real clear when they give advice as to what they are saying. Third, windshield washer fluid is toxic....why get it anywhere near your rv....if you are winterizing properly using the pink stuff the issue is already resolved. No need for anything else.

[GrandpaKip]

wilcamp wrote:
I pour some RV antifreeze in each of the sink/shower drains, to fill the P-traps and run some into the gray-water tank(s). Another gallon goes down the toilet. I don't worry about the cost of RV antifreeze vs. blue windshield washer fluid, this is an affordable insurance policy against the cost of potential damage from freezing/thawing. This is part of the assumed cost of RV ownership and the protection of our investment in this form of recreation.

This is what I do. Just good insurance.

[brownieab]

Use the pink stuff, the drain valves need to stay wet or the seals will leak later

[tglazier]

When you put the pink stuff RV antifreeze in your into your water lines, enough will flow down the drains into your holding tanks. The real danger with freezing are the water lines since they have limited expansion capability. A holding tank with a little bit of water in it has a whole lot of expansion capability.