Winterizing Fresh Water System

[ggray]

I have winterized the potable water system each of the last 16 winters using anti-freeze, with no problems.

So arguably I should do the same again this winter.

But reading what I have about the different types of anti-freeze and potential problems with each makes me consider blowing the lines with compressed air.

Do many of you do this for freeze prevention? I can imagine the pitfalls, but think they can be dealt with.

Comments?

[valhalla360]

It can certainly be done and people do it.

The risk is drips and drops left in the system migrate down and fill a fitting after you are done, then freezes during the winter.

What are you concerned about with using antifreeze? Reality is a lot of foods contain the constituent parts. Assuming you flush the lines, you probably are consuming far more thru food than you get from trace amounts still in the lines.

[canavap]

I used to use antifreeze but hated how long it took to flush the system in the spring and get rid of the taste and smell. I switched over to compressed air and am thrilled every spring. You need to make sure you purge the pump so it doesn't freeze.

I have friends who put a handle of cheap vodka in the lines after they purge the lines just in case. This has no taste. If you are concerned about possible freezing, this may be an answer.

[ggray]

Well, I'm now reading something like the propylene antifreeze may not be so good for some of the parts in the water system (maybe the hoses and some rubber pump components, but also the head hoses where the solution ends up, and which I have just replaced ). And or the other hand, ethylene glycol is toxic.

So I thought about draining all lines and then trying to ensure there was no water left.

I suspect that even if there is a small bit of water collecting in a spot, unless it fills up a fitting, perhaps there would be no damage from expansion.

So I'm looking for personal experiences!

[ggray]

Originally Posted by canavap

I used to use antifreeze but hated how long it took to flush the system in the spring and get rid of the taste and smell. I switched over to compressed air and am thrilled every spring. You need to make sure you purge the pump so it doesn't freeze.

This is what I'm looking for!

I assume you disconnect the line from the pump and blow downstream from there? That would empty the accumulator as well.

My compressor can regulate the pressure (not sure how accurately though) so I thought I'd set at 30 psi. Do you control the pressure you apply?

I would hope not to need to add vodka, especially as I'm not as far north as your friends.

[ranger58sb]

I use air to purge our freshwater system.

First, I drain the freshwater tanks and the water heater. Then purge with a compressor; usually starting at about 30 psi and eventually going up to 40 and then higher sometimes (our PEX system is OK with that). That will also drive a bit more out of the water heater, in our case. (I don't bypass the water heater; the manual says is whatever water is left freeze, no damage will occur.)

Then disconnect the filter/pump/accumulator at each end and bump a bit of AF through -- just enough to get through those parts.

(Some will follow air purging with AF through the systems. I don't do that, mostly because it would best be done with a bypass for the water heater... and I've never bothered to install one.)

In Spring, a quick bump of fresh water through the filter/pump/accumulator will clear that. Reconnect those to the system, and normal commissioning (including freshening) is easy.

-Chris

[valhalla360]

Originally Posted by ggray

Well, I'm now reading something like the propylene antifreeze may not be so good for some of the parts in the water system (maybe the hoses and some rubber pump components, but also the head hoses where the solution ends up, and which I have just replaced ). And or the other hand, ethylene glycol is toxic.

So I thought about draining all lines and then trying to ensure there was no water left.

I suspect that even if there is a small bit of water collecting in a spot, unless it fills up a fitting, perhaps there would be no damage from expansion.

So I'm looking for personal experiences!

Propylene Glycol (RV antifreeze) is relatively non-toxic (if you drink enough pure water, it can be toxic, so everything has some level of toxicity). It is safe enough that it is used as a food preservative. It's not a problem for water systems.

Ethylene Glycol (Automotive antifreeze) is ABSOLUTELY WRONG to use at it has a relatively high degree of toxicity.

The biggest issue with using RV antifreeze is it may take a tank or two of water before the taste dissipates.

You can certainly blow out the system with air but just make sure there are no low points that can collect the trace amounts of water. Lots of people do it. Most have no issue.

For the cost of 2 gal of RV antifreeze, it's not worth dragging a compressor down to the boat in the fall and if each faucet puts out pink stuff, you know it's done. In the spring, we just use water jugs for drinking until we've gone thru a tank or two (we use it right away for washing).

[CaptTom]

I disconnect the supply line from the water tank, and connect that to a hose that goes into a jug of pink antifreeze. I then run the system until every fixture runs pink. I also have a water heater bypass so I can take that out of the system and drain it separately.

This way, there's no "pink stuff" in the water tank or the water heater, only the hoses and fixtures. That small amount is easy to flush out in the spring.

The whole process is very quick, and in Spring it's just a matter of re-connecting the water tank and throwing the valve on the water heater bypass. And I never worry about a small amount of water pooling in the wrong place. Had that happen twice, once in a camper and once in a cottage. I haven't been a fan of trying to drain or blow out the lines since then. Obviously, it CAN be done correctly. I'm just not good at it.

[steamgoat]

I was always confused till I figured, P = Polyprop & People. E = Ethylene & Engine. I drain my tanks, pump pink poly a-feeze thru water system then blow it out with a vacuum cleaner,so,basically its empty but,if I missed any,it has the pink stuff in. Then pump a pint of Ethylene thru the head as apparently its better for the rubber parts. My max/min thermo got to -26F two winters ago,no problems. Water heater is disconnected and drained and blown out with vacuum cleaner,no pink in there as it tastes bad in spring.

[Kita]

I read thru & think ,just wow,,,wow..... first off no Automotive antifreeze in any water that I am drinking, wtf!! Second is holy cow! Man head SOUTH! ! Just my personal opinion but my Little Willy will get far too chilly to deal with that crap, I live in Florida and I want to go south. These boats are in far too cold of water for me...I hope I never have those problems, you guys are hardcore,when I think of how cold it needs to get to freeze my watermaker, ,,,,,,brrrrrrrrr!

[peter loveridge]

I have a simple system, all flexible tanks, and 2 manual pumps, no hot water heater. I make sure the tanks are not full , anything half full or less is ok., and I just leave it. In western nova scotia, doesn't get really cold until mid jan, and warmed up by mid march. Never had a problem. Propylene glycol is less toxic than ethylene glycol, but it's still toxic, If you going to use antifreeze, use cheap vodka, I'm not sure if plumbing antifreeze is entirely safe if you're going to drink from the system

[wrwakefield]

Originally Posted by ggray

I have winterized the potable water system each of the last 16 winters using anti-freeze, with no problems.

So arguably I should do the same again this winter.

But reading what I have about the different types of anti-freeze and potential problems with each makes me consider blowing the lines with compressed air.

Do many of you do this for freeze prevention? I can imagine the pitfalls, but think they can be dealt with.

Comments?

I never liked the aftertaste the RV antifreezes [propylene-glycol based] leaves in the potable water system- even after thorough flushing. And it knaws on some materials in the plumbing system. [Also, I don't like the taste of Pepto Bismol either, and one might get the impression that is why the RV stuff is pink...] Therefore I have always winterized the potable water systems on our boats, cabins, campers, etc. by blowing out the water with compressed air. [Regulate the pressure not to exceed your normal water pressure and you will reduce the risk of having plumbing to repair...]

However, sometimes you have to use the pink stuff on potable systems, and the right stuff works well.

Practical Sailor has a plethora of articles on this topic. If you choose to read only one, this article is worthwhile...

Best wishes deciding what is best for your needs.

Cheers! Bill

[Gamechanger]

I do BOTH blow out the system with compressed air AND add antifreeze to the system. I ALWAYS emphasize use of ethanol-free antifreeze since it is not harmful to any of the rubber seals in the toilet or faucets. I get it at Holland Marine Products.

[knockabout]

fill with rum / decant to a barrel when it warms up / store for next year

[ramblinrod]

Originally Posted by ggray

I have winterized the potable water system each of the last 16 winters using anti-freeze, with no problems.

So arguably I should do the same again this winter.

But reading what I have about the different types of anti-freeze and potential problems with each makes me consider blowing the lines with compressed air.

Do many of you do this for freeze prevention? I can imagine the pitfalls, but think they can be dealt with.

Comments?

I winterize several boats per year.

The trouble with either method, compressed air or propylene glycol, is "Did you get all the water out?"

With compressed air, it is easy to see when water stops flowing out of a tap, but it is possible for some water to stay in a line, and then flow back down to a low point, where it accumulates, freezes, and then busts something.

Therefore, when possible, it is better to apply the compressed air to the high point in the system, for water discharge at a low point (rather than the other way round).

In general it is safer (from a freezing standpoint) to use propylene glycol.

When using propylene glycol, bypass and drain the water heater and freshwater tank. Feed the glycol to the pressure pump inlet, and then open each tap in turn until the anti-freeze runs out. It is wise to measure antifreeze samples from each tap to ensure it is not diluted. Diluted propylene glycol is not very effective freeze protection.

If possible, avoid putting anti-freeze directly into the fresh water tank, or into the water heater, as this consumes a lot more anti-freeze than necessary, and takes 4 or 5 freshwater flushes in the spring, to dilute the remaining anti-freeze enough one cannot smell or taste it.