Dry Ice in the Ice Box ?

[shibbershabber]

I am looking for ideas to make the ice box actually cold... ANYTHING... some reduction in temperature. Its basically a cupboard.

I am planning on installing a refer system in it soon, but in the mean time I am using a cooler set in the cockpit filled with ice.


I have never used dry ice for anything, but it seems like it would be a good idea. It evaporates as it thaws so there is no drainage to worry about.

So have any of you used it? Is it expensive? hard to find? Somehow incompatible for boat use?

thanks!

[Minggat]

I've done it. Short term it works great. Find a party ice outfit near you. Google "dry ice cautions".

[sailorgal]

Make sure you only do this in a well-ventilated area. Dry ice is CO2, and as it dissipates, it has to go somewhere.

[admisgd]

We use dry ice a lot. Works great don't put anything next to it you don't want frozen. We have a full size fridge, but it is AC so we buy 2 sheets and put one on the bottom shelf and one on the top shelf keeps everything ice cold for several days, no need to turn on the generator. I'm not sure about availability in Oregon, but dry Ice is readily available in most bait shops in FL and a lot of grocery stores.

[GordMay]

Originally Posted by sailorgal

Make sure you only do this in a well-ventilated area. Dry ice is CO2, and as it dissipates, it has to go somewhere.

Dry ice is frozen (-109̊F, -79̊C) carbon dioxide (CO2).

It releases the CO2 as it sublimates (changes directly from solid to gas).

Carbon dioxide vapour is substantially heavier than air. In confined, poorly ventilated spaces it can displace air, causing asphyxiation. It is even possible for CO2 vapour to accumulate in low-lying areas, out-doors, under zero or very light wind conditions.

Do not store dry ice in a container that is completely airtight. As the ice sublimates to CO2 gas, it will cause an airtight container to expand and possibly explode.

[Amgine]

We tried dry ice last year, and it was a far greater success than we expected, depending on your measures of success.

I purchased 2 25# blocks, which was slightly more than half the refer volume. We'd been cruising for a couple weeks already, so we had some leftovers and fresh foods, as well as canned and bottled beverages. Since ice was lasting a couple days, I hoped to get at least the same.

The exploded bottled/canned beverages didn't melt for almost two weeks. The frozen meats were removed in the morning in time to be thawed for evening dinners. After 5 days we were able to put fresh produce into the basket at the top of the ice box and they wouldn't freeze, but the strangest thing happened: after a couple days in the ice box they became carbonated. This was great for the cherries, not so great with the sugar snap peas.

Due to lack of forethought the icebox was an absolute mess to clean up. Dry ice will turn your icebox, at least temporarily, into a seriously cold freezer, exploding products not designed to be frozen. We purchased a sink stopper for the drain, hoping to keep the cold CO2 from draining into the bilge: this worked very well - it froze in place. The dry ice lasted 15 days. I was acutely aware of smell of CO2 in the boat, and it was noticeably stronger toward the cabin sole, so we slept in the cockpit several nights and never closed up the cabin or shut off the fans at night - which resulted in more engine running to keep the batteries topped up.

Conclusion: dry ice worked very well, lasted longer than expected, but was also much more expensive than expected: not cost efficient. It would have been a dream to clean up if we had known how cold it was going to keep things. Due to fears about CO2 poisoning it severely disrupted my enjoyment of that portion of the cruise.

If dry ice were readily available in my cruising range - which it isn't - I'd consider getting a much-smaller amount of it once a week or so instead of ice to test if it was the sheer quantity which caused the strong smell of CO2.

[SabreKai]

I agree, it works well with a little forethought but as mentioned, the gas is heavier than air so if your cooler/icebox is inside, I'd be very careful to run your bilge fan every few hours just to make sure you don't go to sleep and never wake up because the gas level rose over the bunk top.


Sabre

[bluzzin]

You can get dry ice at Fred Meyers in Oregon. Usually right by the check out counter area.
michael

[Therapy]

Originally Posted by SabreKai

I agree, it works well with a little forethought but as mentioned, the gas is heavier than air so if your cooler/icebox is inside, I'd be very careful to run your bilge fan every few hours just to make sure you don't go to sleep and never wake up because the gas level rose over the bunk top.


Sabre

Carbon dioxide and carbon monoxide are not the same, nor are it's effects on the body.

CO2 levels rising will trigger your breathing to get deeper and more rapid. It is how we keep breathing. CO2 goes up, we breathe more. It goes down and we breathe less.

CO displaces O2 in the blood stream and is not noticed by the brain. The brain monitors CO2 levels. I does not know about CO. Then your brain fails.

Still not recommended to stay in areas of high CO2 concentration as it causes agitation and ultimately panic. You won't die, you will attempt escape.

A really "old" submariner may explain it better and also why the survival equipment included soda lime. It absorbs the exhaled CO2 so you don't breathe it and your brain is fooled, so less panic aboard.

[sarafina]

I am thinking of trying this stuff. Has anyone else tried it?
http://www.techniice.com/english/index.htm

[svHyLyte]

Dry ice will work but it takes up room and gives you nothing back. Try freezing bottles of water or Gatoraid instead. They will last quite a long time if the top of the box is covered with an insulating blanket and as they thaw you can use them.

FWIW...

[virginia boy]

Originally Posted by GordMay

Dry ice is frozen (-109̊F, -79̊C) carbon dioxide (CO2).

Originally Posted by GordMay

It releases the CO2 as it sublimates (changes directly from solid to gas).

Carbon dioxide vapour is substantially heavier than air. In confined, poorly ventilated spaces it can displace air, causing asphyxiation. It is even possible for CO2 vapour to accumulate in low-lying areas, out-doors, under zero or very light wind conditions.

Do not store dry ice in a container that is completely airtight. As the ice sublimates to CO2 gas, it will cause an airtight container to expand and possibly explode.

Just guessing here ... but, if from the icebox a vent tube the size of a pencil were led up and out of the cabin, it would solve the gas and pressure problems. Since the tube would be above the level of the icebox there would be no heat loss.

[stark]

I wouldn't worry so much about dry ice.

A 30' boat has close to 60 kg of air inside the cabin. If you have 1 or 2 kg of dry ice that takes several days to sublimate, your not going to notice a difference. Anyhow, typical person exhales on the order of a kilogram of CO2 per day.

[bstreep]

A couple of years ago for a long weekend, we took one of those massive coolers typically found on sportfishermen, and put 8 lbs of dry ice in the bottom. We then covered it with 2 layers of bags of ice cubes. We then loaded up the rest of the cooler with about 10 cases of drinks. The next morning, about 1/2 the drinks were frozen solid!

Use less than you think you will need, and try it out first. We've since used it several times, and it really works very well.

[Therapy]

Originally Posted by virginia boy

Just guessing here ... but, if from the icebox a vent tube the size of a pencil were led up and out of the cabin, it would solve the gas and pressure problems. Since the tube would be above the level of the icebox there would be no heat loss.

CO2 is heavier.

Down and out is the way to go I suspect.

Of course if the bilges fill and stay filled then fire is less of a problem.