Winterizing... Are These Steps Critical

[ranger58sb]

Originally Posted by S/V Illusion

If anyone actually fills their heater with antifreeze, you are wasting antifreeze. The antifreeze manufacturer may thank you but you just wasted your money.

The residual water won’t harm anything given it has lots of space in which to expand.

Yes. Our water heater manul specifically says is any residual water (i.e., after draining) freezes, it won't hurt the tank.

Originally Posted by Dockhead

The average low temperature in Wilmington in the coldest month, January, is only -4.1C, with average high +4C. Is there really much risk of anything freezing inside a boat in the water in such a climate?

Yes. Especially plumbing above the water line, e.g., cockpit showers, etc. Sometimes this below-freezing temps last for weeks. And our marina routinely freezes over for a few weeks at a time. Not always, but often enough to make gambling unattractive. (I suspect Scarlet's marina will freeze over too, given its off the direct path of free-flowing tidal waters... unless the marina itself is running a boatload of de-icers.)

-Chris

[S/V Illusion]

Originally Posted by Dockhead

The average low temperature in Wilmington in the coldest month, January, is only -4.1C, with average high +4C. Is there really much risk of anything freezing inside a boat in the water in such a climate?


Remember the water will always be plus (or else it won't be water anymore ).


I am pondering this question myself, with my boat in the water in Denmark with average low temperature in January of -1, with average high of +1. Average sea temperature in January is +2. I would like to keep sailing during the winter and don't want to have to re-winterize after every trip.

As most of us know, “average” implies that the temperature is below that 50% of the time.

Also, propylene glycol solution typically sold for consumption is not 100% glycol on which your misleading chart is based. Consequently, glycol sold in gallon jugs such as boaters typically use cannot be diluted by mixing without adversely affecting its efficacy. The “slush point” decreases drastically upon mixing.

[scarlet]

Originally Posted by CarlF

Why not schedule a trip back in mid December to generally check on the boat? This will be before anything inside could get in trouble from freezing. And it's better than worrying all winter.
.

We just booked it.

[Dockhead]

Originally Posted by S/V Illusion

. . . Also, propylene glycol solution typically sold for consumption is not 100% glycol on which your misleading chart is based. Consequently, glycol sold in gallon jugs such as boaters typically use cannot be diluted by mixing without adversely affecting its efficacy. The “slush point” decreases drastically upon mixing.

Why is the chart misleading? It's totally straightforward.


When I left my boat out for a whole winter some years ago (when I had my mast out for re-rigging), I winterized, and bought 100% propylene glycol, which I had no trouble finding. I later found out no one does this in this place (Cowes, Isle of Wight), as freezing does not take place inside boats even on the hard, in a climate where it might reach -10C, but normally thaws during the day.


But even if you are buying 50% propylene glycol, the handy and non-misleading chart shows you that you can dilute it by another 50%, for 25% total, you are still good to -13C or so, which is a temperature impossible to reach in your bilges anywhere on any U.S. coast.


There is most certainly no "loss of efficacy if you dilute it even a little". The freezing temperature goes up smoothly with dilution, just like with ethylene glycol. So adding propylene glycol to a system which still has a bit of water in it should be no problem, unless you are buying the weak pre-diluted 50% stuff and there is more water in the system, than antifreeze you add.





https://www.buychemicalsdirect.com/v...eeze_chart.pdf

[scarlet]

Originally Posted by ranger42c

Yes. Our water heater manul specifically says is any residual water (i.e., after draining) freezes, it won't hurt the tank.




Yes. Especially plumbing above the water line, e.g., cockpit showers, etc. Sometimes this below-freezing temps last for weeks. And our marina routinely freezes over for a few weeks at a time. Not always, but often enough to make gambling unattractive. (I suspect Scarlet's marina will freeze over too, given its off the direct path of free-flowing tidal waters... unless the marina itself is running a boatload of de-icers.)

-Chris

They have bubblers, and We've talked to other boaters there who leave theirs in the water, and the water stays open...

[Dockhead]

Originally Posted by S/V Illusion

As most of us know, “average” implies that the temperature is below that 50% of the time. . .

Sure, but just because the outside air temperature momentarily reaches a certain level doesn't mean the temperature in your bilge will ever reach anywhere near that temperature.


I just came back to my boat after a couple of weeks, and it was -3C outside when I arrived, and ice on the decks. But inside the boat it was +10C. No heat running.

[scarlet]

Originally Posted by Dockhead

Sure, but just because the outside air temperature momentarily reaches a certain level doesn't mean the temperature in your bilge will ever reach anywhere near that temperature.


I just came back to my boat after a couple of weeks, and it was -3C outside when I arrived, and ice on the decks. But inside the boat it was +10C. No heat running.

I actually wondered about this myself... With us having a Lagoon.. there are lots of big windows, and we tied back all curtains so that the sun could shine in over the winter. was wondering how much of a difference that makes..

[S/V Illusion]

Originally Posted by scarlet

I actually wondered about this myself... With us having a Lagoon.. there are lots of big windows, and we tied back all curtains so that the sun could shine in over the winter. was wondering how much of a difference that makes..

As most of the plumbing and tankage is, as they way, "where the sun don't shine"and enclosed which can create an insulating effect, the affect of radiation heating by the sun can be significantly mitigated from what you might assume.



I suspect most people would not want to depend on radiational heating regardless of it's affect.

[redneckrob]

Originally Posted by S/V Illusion

As most of us know, “average” implies that the temperature is below that 50% of the time.

Also, propylene glycol solution typically sold for consumption is not 100% glycol on which your misleading chart is based. Consequently, glycol sold in gallon jugs such as boaters typically use cannot be diluted by mixing without adversely affecting its efficacy. The “slush point” decreases drastically upon mixing.

Dockhead is right and you've been blessed with an opportunity to learn, don't squander it! The freeze properties of propylene glycol vs dilution very clearly follow a curve and the bottle tells you what you're starting with, so it's easy to calculate what dilution effects are and they're not nearly as dramatic as you thought. Like I said, great opportunity that you learned something you didn't know before today, not a chance we get every day!
Also, as an FYI the "slush point" isn't actually what you're worried about, it's designed to slush at a fairly high temp compared to the freeze point. Nothing gets damaged until it actually freezes.

[Dooglas]

Originally Posted by S/V Illusion

If anyone actually fills their heater with antifreeze, you are wasting antifreeze. The antifreeze manufacturer may thank you but you just wasted your money.

Filling the water heater with RV antifreeze does more than waste money. The antifreeze attacks the anode in the water heater.

[S/V Illusion]

Originally Posted by redneckrob

The freeze properties of propylene glycol vs dilution very clearly follow a curve and the bottle tells you what you're starting with, so it's easy to calculate what dilution effects are and they're not nearly as dramatic as you thought. Nothing gets damaged until it actually freezes.

Unfortunately, some myths are hard to correct, this being one.



Clearly you wont believe what I said so ask the manufacturer (s) why they specifically list among the cautions on labels the words "do not dilute". There is a lesson therein only people who think they know everything won't learn.



I'm just trying to help people from making a mistake. That is a lesson worth learning.

[Juho]

- In our boat emptying the water heater is not quite straight forward. It has a small valve to empty it, but it is best to use also some air (vacuum cleaner blowing air in reverse mode to a tap) to get all the water out.

- Our motor has antifreeze in it. Don't trust just opening the seacock, impeller etc unless you really know that you will get all the water (or enough of it) out that way.

[Juho]

Originally Posted by Dockhead

I am pondering this question myself, with my boat in the water in Denmark with average low temperature in January of -1, with average high of +1. Average sea temperature in January is +2. I would like to keep sailing during the winter and don't want to have to re-winterize after every trip.

If you have electricity, how about a small electric heater and a heat watch device that sends you a text message when the temperature gets too low (or if the boat loses electricity). You might also be able to switch the heater on remotely (with a text message) when needed.

[ramblinrod]

Of course, a simple solution would be to just call a local mechanic.

For a few hundred bucks you get it done right, don’t loose any sleep, don’t waste the travel time, and don’t have an expensive repair bill in the spring.

[redneckrob]

Originally Posted by S/V Illusion

Unfortunately, some myths are hard to correct, this being one.



Clearly you wont believe what I said so ask the manufacturer (s) why they specifically list among the cautions on labels the words "do not dilute". There is a lesson therein only people who think they know everything won't learn.



I'm just trying to help people from making a mistake. That is a lesson worth learning.

The manufacturer of the product I use provides a table showing the impact of dilution and no caution stating "do not dilute". I couldn't tell you why your manufacturer states otherwise, although if they print a given freeze point and don't print the dilution/freeze point curve it makes sense that they'd say that. Some manufacturers aim toward the lowest common denominator and assume their customers would be confused by the bit of math and chart reading that entails so they print a number and say "do not dilute" which is technically correct if you want to achieve that number and don't want to confuse anyone with the dilution calculation. There's a marketing reason to do that as well, if a technically correct but easily misinterpreted warning causes at least a few folks to buy 10 gallons of -50 when you could buy 5 gallons of it and dilute it 50/50 because you need much less you sell half as much!But bottom line it's basic chemistry, lots of other sources you can go to in order to calculate the freezing point of the substance at various dilution levels. I wouldn't ask anyone to "believe what I said" in any event but especially when there's ample evidence, provided here online and available to anyone with a basic knowledge of chemistry, that "what I said" was simply incorrect. I'm just trying to help people from making a mistake. That is a lesson worth learning.

I could certainly call the manufacturer of the chemical, but I would say that reading the literature they provide and my very basic college chemistry 101 background makes that superfluous. However I would encourage you to call your manufacturer, just make sure you talk to a scientist or engineer and not the call center guy who's going to be instructed to treat everyone as the lowest common denominator same as their bottle warnings

And please, "There is a lesson therein only people who think they know everything won't learn." in response to those who posted detailed freeze point versus dilution curves and discussed the chemistry behind it in response to an unsupported assertion? Seriously? I'm sure you are a kind, intelligent, and respectful person. I think we can all agree that that sentence was not kind or respectful. I will be the first person to say I don't "know everything" and I'm more than eager "to learn". If you would like to explain how we're all misreading the curves or misunderstanding the chemistry I for one would love to learn from that and would very much enjoy a chemistry and physics discussion with a like minded person who is equally sure that they don't "know everything" and is equally eager to learn. Deal?