Metal plates as thermal mass in freezer?

[Lunita]

Has anyone used non food items in their freezer to hold the temperature down. I wondered about putting some thick aluminum plate material in the freezer and fridge to act like holding plates. They would not take up a lot of room and would allow longer times between compressor run cycles?

[Reefmagnet]

Put in appropriate sized bottles of water. They'll do the same job and also provide cool refreshing drinks as needed.

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[Lunita]

Thanks, yes I have used water. Actually I freeze water with lots of salt added. Freezes at a lower temperature and stays cold way longer. I use salt water jugs for the ice box, but cautiously as they are cold enough to freeze the items next to them!
I was thinking the aluminum plates would take up a lot less useable space.

[a64pilot]

You want a liquid that freezes. The phase change from solid requires a lot of energy, keeping score things colder, longer.
Water is nearly ideal, there are better liquids, but you can,t drink them. A frozen gallon of water in a milk jug is an ideal ice chest cooler for trips to the beach etc, and of course you drink it as it thaws too.


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[model 10]

Originally Posted by Reefmagnet

Put in appropriate sized bottles of water. They'll do the same job and also provide cool refreshing drinks as needed.

Sent from my SGP521 using Cruisers Sailing Forum mobile app

That's the only problem with beer or beer containers anyway. I'm fine with frozen bottles of water but it's not ice cubes so what good is it? I would rather fish out a few cold ones and let them defrost but the damn lids pop off. Are cans more safe?
From what I hear frozen steak is the best ballast.

[wrwakefield]

Originally Posted by Lunita

Has anyone used non food items in their freezer to hold the temperature down. I wondered about putting some thick aluminum plate material in the freezer and fridge to act like holding plates. They would not take up a lot of room and would allow longer times between compressor run cycles?

Lunita,

We fill the voids in our dedicated freezer with various sizes of Blue Ice to help improve efficiency and quick freeze new items added to the freezer by surrounding/sandwiching them with Blue Ice.

That allows us to remove some of the Blue Ice when more freezer space is needed, or put some in the refrigerator when we load it with warm items to off-set the load, and of course put some in a cooler [meals/beverages, etc.] when we commute off the boat.

And lets not forget about lumps, bumps, burns, and black-eyes... [We use the soft gel packs in these cases...]

This is just another way of accomplishing what you asked about. There may be better portable eutectic products than Blue Ice- I just mention it as an example and because it just happens to be what we have at this moment...

Cheers!

Bill

[Reefmagnet]

A 2 litre bottle of frozen water will keep the beer cool in my Engel car fridge (unpowered) for three days in the tropics. Sometimes it's nice to gulp some cool water before hitting the grog

[Lunita]

Yes drinkable water is a plus.
The idea here however is the compact flat metal plates would still allow useable space in a maxed out little under counter fridge.
Maybe some version of the fluid filled metal holding plates from a proper holding plate refrigerator which could be stacked in the refrigerators freezer compartment? I already have a separate top loading freezer so that tiny little freezer in the fridge isn't needed for food.

[colemj]

Unless you are using a eutectic solution, there is no thermal storage to be gained in a freezer by just adding random mass (your salt water helps here, and the blue ice is a eutectic). Aluminum would be about the worse in this application.

Even for a reefer, bottles of water won't work because you will just spend the energy re-cooling them after you take a drink. It takes very little energy to remove the heat from dead air.

Mark

[StuM]

I keep at least a dozen 600ml bottles of water frozen in the bottom of my freezer. It serves several purposes:

1. Thermal mass
2. The freezer is so deep that it's a long reach to the bottom. The stacked water bottles make it easier to get to the stuff at the bottom and there is still enough room for our needs.
3. Keeps the esky contents frozen when I take everything out of the freezer to defrost.
4. Emergency water reserve.

[senormechanico]

Eutectic solutions:

http://www.amazon.com/s/ref=nb_sb_no...rds=arctic+ice

Arctic Ice is for refrigerators and Arctic Tundra is for freezers.
Note the phase change temps. Ice +33.8f, Chillin +28f and Tundra +5f .
We use the biggest size
Tundra when on vacation and want our fridge to work harder using the extra available solar and thereby boosting the apparent size of our fridge/freezer.
We built an insulated bag out of Aerogel specifically made to hold one of the biggest Arctic Tundra cells.
With two Tundras, we switch them once a day.
It's like having a MUCH bigger freezer.
We use the refrigerator version (Ice) with the same bag for a refrigerator if we're only going out for a week or so and don't need more freezer space.

[newhaul]

Originally Posted by colemj

Unless you are using a eutectic solution, there is no thermal storage to be gained in a freezer by just adding random mass (your salt water helps here, and the blue ice is a eutectic). Aluminum would be about the worse in this application.

Even for a reefer, bottles of water won't work because you will just spend the energy re-cooling them after you take a drink. It takes very little energy to remove the heat from dead air.

Mark

Mark eutectic is not a solution but the word that identifies the point at which phase change happens from frozen solid to a liquid state which with a 23% salt/water solution happens at approximately -6° f a much better solution to use would be ethylene glycol in a 40% solution would be best with a freeze temperature of approximately -10°f or even a 30% solution with a 7°f freeze point.

[SV THIRD DAY]

"Eutectic Solution" is an industry standard way to say it.
Solution is the Noun and Eutectic is the Adjative. Wow...did I just diagram a sentence on cruisers forum? Ban me for a week!

We use a 30-40% solution of Glycol/water for a freezer plate and 10% for a refrigerator plate. The next thing you know we will be arguing about what is and isn't a "true eutectic solution".

But as for adding metal...it just can't store enough "cold BTUs" to do you any real good.

[newhaul]

Originally Posted by SV THIRD DAY

"Eutectic Solution" is an industry standard way to say it.
Solution is the Noun and Eutectic is the Adjative. Wow...did I just diagram a sentence on cruisers forum? Ban me for a week!

We use a 30-40% solution of Glycol/water for a freezer plate and 10% for a refrigerator plate. The next thing you know we will be arguing about what is and isn't a "true eutectic solution".

But as for adding metal...it just can't store enough "cold BTUs" to do you any real good.

For that grammar diagramming lesson you should be forced to put an additional coat of paint into on your hull.

[newhaul]

He said he would be putting it in the little freezer compartment hence my 30% to 40% recommend.