ice chest option

[MrBill_FLL]

I'll add,
if you can get solid blocks its should last longer than the 'blocks' you get at 7-11.

I like to use 1/2 or 1 gallon milk jugs I freeze myself with my filtered water. (not sure if that will be possible in AZ)

I have some 5 day coolers and can keep ice 4 days if properly packed.

on longer trips I bring 1 spare cooler full of ice and frozen bottles and reload the primary on 2nd day. that spare cooler becomes the trash can.


-Walt, can you feel the cold on the outside of the box? I'm also surprised the ice doesn't last longer. (can any more foam be added?) -do you have one of those thermal (IR thermometers?).

 

[Doc_holiday]

I have a Coleman extreme cooler it's held ice for 4-5 days but the second bag of ice lasted even longer (probably has to do with the pre-cooling you mentioned. Also I have noticed as pointed out when it's full of product, it last longer. Of course if I drop a 10 pound turkey directly from the oven in, the ice would be gone a lot quicker. Same goes for beer. From the fridge to the cooler is better than from the shelf at the 7-11.

Exposure to direct sun plays into it, but that should t be an issue down in the cabin. The Ambient temp does too. The larger the temperature difference, the faster the heat transfer.

I don't know what the R value of that cooler is tho.

I do like the overall experiment you are doing. I think we all benefit from the discussion and experience.

If the cooler has a drain, make sure it's got a valve or is trapped. I've seen cold air lost out the drain.

As far as the frozen milk jug goes, I have no experience there. I do know that it's the change of state that is the workhorse. May last longer but have a slower transfer of heat. Also surface area comes into play. Ice cubes from a bag will have more surface than a block. 10 pounds of ice is still 10 pounds so an ice block may not give you the same hourly btuh transfer, it should last longer than the cubes. It's burning the candle at one end or both.

 

[walt]

I think part of the problem may be that there is about 99 quarts volume inside.. more surface area to leak.

When I first put ice in there with the fan running, I just had the lids held down by gravity and I could feel cold air on the ice side but nothing on the food side. I think the fan was putting a slight high pressure in the ice side (so air leaked out) and low pressure on the food side - and you would not feel anything from the air leaking in.

Since then I have some clamps on the lids so I "think" I’m not getting any air leaking. I have access to one of those temperature measurement guns so may try that sometime..

For the drain, I have a PVC pipe that goes though the foam to a drilled hole in the inner box. The inner box is all epoxy/ glass taped and sealed and I used some 5200 fast dry to seal the PVC pipe to the inner box. It’s all hardware store stuff for the drain on the outside, just unscrew that cap to drain. When the drain cap is open you can feel a nice flow of cold air coming out.

 

[Doc_holiday]

You could add ice cream salt to the ice block. It would increase the change of state rate and give you a colder box, just won't last long.

Try wrapping the cooler with bubble wrap making sure to tape the seams. It may add significant r value but there's a secret to that. Tape 1/4" slats to the box before wrapping it so there is a gap between the bubble wrap and box. Might add 5 or 6 to the r value. If you don't like the looks, put it on the inside.

You could go to an hvac supply house and get a sheet of duct board. It's a compressed fiberglass with a fail face. Use foil tape to get the seams and use an iron to set the glue. The supply houses also carry a foil bubble wrap that would be more attractive and more robust. Again the key is rather air gap between the surface and the bubble wrap.

 

[Tom G P-21]

Here is a simple fan for circulating air in a refrigerator. I've used these in our three way fridge in our camper. They really do last a long time on two D batteries.

http://www.campingworld.com/shopping/item/fridgecool-fan-with-on-off-switch/38134

 

[walt]

Time to modify.. I don’t want to mess with the outside of the ice chest.. it already is something only I will remotelly think sort of looks nice. However I do want to add some insulation. The height driver on the inside food area is that a plastic one gallon jug of milk fits in their upright and I have some room here so I’m going to raise the floor. Seems like the flloor would be the best bang for the buck to increase insulation and R value.

What I’m going to put in there for the additional insulation (there is 2 inches of styrofoam already in the floor) is just the old high density foam shown in one of the pictures. This is an old back packing pad and is 5/8 inch thick. I will add another 5mm piece of plywood on top and then re-seal everything with epoxy and glass. Since I already had the drain in place in the ice area, I’m having to raise it a little in order to raise the insulation on the inside.. Oh well.. It’s a prototype experiment..

Also, when I did the test before, I had the cooler raised up off the ground by registration blocks that will eventually hold the ice chest in place on the boat. So I had air flow UNDER the ice chest. When I actually get the ice chest in the boat (not until November), I won’t have this air flow under the chest so this should help.

Power on the fan.. yes very low. I added a high brightness blue LED and a switch (which you can see it taken apart in the picture) but run the LED with only 2 ma. Both the fan and the LED burn barely over 0.06 amps. If I run the fan for 1/2 of each day, Ill use only about 3/4 of an amp hour each day - almost nothing.

Doc Holiday, any comments about that high density foam before I get it all epoxied in place and can’t remove it?

 

[Winkfish]

Do you think the wood itself might be absorbing some of the cool air, more than a plastic type material, like on the inside of ice chests?

 

[walt]

Probably.. although I think it still provides some insulation. ????

I ended just adding 1 more inch of foam (same hardware store insulation stuff) as I had room to do this and the one gallon jug of milk still fit upright. So now I have 3 inches thick foam on the bottom and 2 inch thick everywhere else.

 

[Winkfish]

I'm looking forward to see how your experiment plays out.

 

[Kestle]

I'd like to suggest you don't add foam to the floor, but add foam to the underside of the bunk of about two inches.

That should reduce the conduction part and keep the floor from being warmed by the hull.

Jeff

 

[walt]

I think that is a good idea and will probably do something like that..

I already did add in a new floor on the inside - 1 inch of styrofoam and 5mm plywood above the old floor and soon will do another test with both the new 3 inch bottom plus the air flow restricted on the bottom side of the chest. Its a change of two variables but I should at least find out if the bottom is where I was losing the heat.. Im also going to run the fan again for this test. I have another variable (weather in Denver in Sept..) so am hoping to get this goiing today.

 

[walt]

Update..

I started this test yesterday and put a 10 pound block of ice in the new version of this two chamber chest with the 3 inch thick bottom and 2 inch thick sides. The fan has been running the whole time.

I also put a 10 pound block of ice in a "5 day" Coleman cooler.

Its not yet one day but the two chamber ice chest is running about 3 or 4 degrees cooler in the food area than the 5 day plastic cooler even though the thermometer is very close to the ice in the plastic cooler (as is every thing else).

Neither will make 5 days but the two chamber cooler is still melting the ice significantly faster that the plastic cooler.

I think that heat sink the ice is sitting on works a little too well if the fan is running..

Ill finish this test but Im thinking about a new heat sink that is much less effective at sucking the cold out of the ice. The cooler wont work as well - but hopefully not go through the ice so fast..

On the other hand, the two chamber cooler sure is a lot nicer to use than the plastic 5 day cooler..

 

[EnginesForward]

Update..

I went ahead and made this "electric ice chest" idea for my Mac 26S and have a little test time on it now with mixed results. The first picture shows the general configuration and there is a .75 watt fan blowing air over ice sitting on an aluminum heat sink in one chamber and the cold air comes in at the bottom of the larger food chamber. The second picture shows a mockup of where it will go in the 26S.

The good thing is that the chest is fairly good at transferring the cold of the ice to the food chamber. I had a little fridge thermometer in the food area and the temperature stayed about 44F - which is somewhere between where a fridge and an ice chest would run.

The negative result was that if I left the fan on all the time, I got just less than 2 days on a 10 pound block of ice. The ice chest has 2 inches of insulation foam on all sides so an R value of maybe 10 and for an ice chest, I think the ice should have lasted longer but I think that circulating air increases the heat flow to the outside. I had the lid clamped down during this test so no air should have been leaking in our out - except when I was checking things which was probably too often.

So.. just partly successful. It will still make a good ice chest and I put a switch on the front so that I can turn the fan off and on which I think will result in slightly warmer temps inside but the ice hopefully will last longer..

It ended up weighing 45 pounds and has nice "Wal-Mart furniture" styling

Hint,
I have used Dry-Ice to keep thing cold. I can keep meat frozen in plastic freezer bags then wrap them in newspaper the will stay frozen if you put them on top of the Ice. other food and drinl cans can go in after. Main advantage is that the dry-ice evaporates and leaves no watery mess. A couple of small pieces willl las about a week.

 

[walt]

This ice chest needs to work getting ice from a marina - get ice every few days so it needs to work with whatever cold stuff is available.

I didnt size dry ice however.. Do you happen to know about the size it typically comes in? Cost for this size. Not important to know.. but if you have that info easy..

I know a single 10 pound bag or block of ice will fit in the ice chamber, I think a 20 pound bag of ice will fit. Since I raised the floor, I dont think two fresh 10 pound blocks will fit any longer.

I did a bad thing experiment wise and changed the heat sink to just an "ice stand" in the middle of the experiment.. so I can no longer compare to the 5 day chest. Oh well.. I know the two chamber chest was going to use up the ice block sooner anyhow after one day. Its running agaiin with the same block as before - about 4/10 the original size. The new ice stand is about one pound lighter than the heat sink.

 

[philwsailz]

I would be real scared of using Dry Ice in a boat. It is Carbon Dioxide.... And it is heavier than air.

As a kid I took some on a family car trip, wrapped up in my suitcase; my dad didn't know. We were all having a hell of a time staying awake in the car. When my dad found out why I was real close to a beating.

That dry ice got tossed right to the side of the road, right then and there. I have to believe that in a boat, your heavier than air gasses escaping from the ice chest would settle in the bilge first, and slowly fill the boat.

I will not be carrying dry ice on my boat. I almost killed my family once; no need to repeat that experience....

 

[walt]

Ill post this before I forget the results - both the plastic five day and the two chamber cooler melted all the ice (one ten pound block put in each chest). When the ice is near melted, both coolers have the inside temperature raise but I would say the five day cooler lasted about 52 hours and the two chamber cooler lasted about 48 hours with the fan constantly running.

I was hoping for longer than 48 hours.. but I guess that is about all it will get. On the other hand, the two chamber chest is a lot nicer to use and the water will be easy to drain. I also attached the picture of the five day ice chest near the end of test.

I screwed with the two chamber configuration during the test making the results no longer "apples to apples". At about 28 hours or so, I had drained the water from the two chamber test and put in the plastic ice shelf instead of the aluminum heat sink. Before I did this, the two chamber chest was running about 3 degrees cooler, after I did this, the two chamber cooler was running about 3 or 4 degrees warmer. So.. I don’t like the plastic ice shelf.

The original aluminum heat sink worked a little too well so I removed some of the Al plates in the heat exchange area and also drilled a bunch of holes in the bottom to reduce surface contact area with the ice. This also got rid of about 0.8 pounds which Im always concerned about since my particular boat sails (and trailers) better if kept as light as possible. I probably wont do another ice block test until I put the cooler in the boat in November (boat is at Lake Havasu AZ, cooler is in Denver).

So.. only partly successful and not as convenient or nice as an electric fridge and goes through ice faster than a five day cooler. But the way I plan to use it, it will end up with about 50 times smaller power load compared to the electric fridge (almost nothing) so my existing electrical system wont need any changes. And I can always put a block of ice in the food area and use it like a conventional ice chest. Or one block in the ice chamber, one block in the foot chamber.

 

[monkeybars]

Ill post this before I forget the results - both the plastic five day and the two chamber cooler melted all the ice (one ten pound block put in each chest). When the ice is near melted, both coolers have the inside temperature raise but I would say the five day cooler lasted about 52 hours and the two chamber cooler lasted about 48 hours with the fan constantly running.

I was hoping for longer than 48 hours.. but I guess that is about all it will get. On the other hand, the two chamber chest is a lot nicer to use and the water will be easy to drain. I also attached the picture of the five day ice chest near the end of test.

I screwed with the two chamber configuration during the test making the results no longer "apples to apples". At about 28 hours or so, I had drained the water from the two chamber test and put in the plastic ice shelf instead of the aluminum heat sink. Before I did this, the two chamber chest was running about 3 degrees cooler, after I did this, the two chamber cooler was running about 3 or 4 degrees warmer. So.. I don’t like the plastic ice shelf.

The original aluminum heat sink worked a little too well so I removed some of the Al plates in the heat exchange area and also drilled a bunch of holes in the bottom to reduce surface contact area with the ice. This also got rid of about 0.8 pounds which Im always concerned about since my particular boat sails (and trailers) better if kept as light as possible. I probably wont do another ice block test until I put the cooler in the boat in November (boat is at Lake Havasu AZ, cooler is in Denver).

So.. only partly successful and not as convenient or nice as an electric fridge and goes through ice faster than a five day cooler. But the way I plan to use it, it will end up with about 50 times smaller power load compared to the electric fridge (almost nothing) so my existing electrical system wont need any changes. And I can always put a block of ice in the food area and use it like a conventional ice chest. Or one block in the ice chamber, one block in the foot chamber.

A lot of trouble for nothing, save time and just spend the money on one of the high quality ice chests that are made, that are truly 5 day. Hint none are made by coleman or igloo. they are in the 4-5 hundred dollar range but well worth it.

 

[walt]

Yep, I partly agree that just stick with a good conventional ice chest.. they overall work just fine. But then I would have missed out on all the fun I had with this project and if nothing else, I probably have a good quality conventional ice chest - with an easy way to drain it (I put the drain in a spot that is out of the way but should be convenient. I probably have a "couple hundred" bucks into this but really didn’t keep very good track of the costs.

I was talking to someone last night and they were telling me about some ice chest that you can no longer find. It was orange or something like that and had a place in the lid for some sort of "something" that you would remove from the underside of the lid, stick in freezer and then attach back to the underside of the lid. Apparently it worked very well. Name started with an "O" or something like that.

Monkybars.. maybe Ill see you this winter..

 

[MrBill_FLL]

I was talking to someone last night and they were telling me about some ice chest that you can no longer find. It was orange or something like that and had a place in the lid for some sort of "something" that you would remove from the underside of the lid, stick in freezer and then attach back to the underside of the lid. Apparently it worked very well. Name started with an "O" or something like that.

Monkybars.. maybe Ill see you this winter..

Gott,

http://www.rubbermaid.com/Category/...tId=MarineCoolers&Prod_ID=RP091226&Redirect=1


I had one of these w/o the ice packs, it was just ok for keeping food. this was purchased long before the 5 day coolers came out.

it was strong, and sturdy. used it for a fishing platform on front of skiff. (starboard screwed to top).

in its day it was better than the igloos. (90's)


Walt, you might try to cut some high density foam to lay over the opening (double the lid density. we do that.. the tops seem the thinest.)

Dry ice is sold by the pound around here.. I forget the price, but not cheap. I would only use that above deck....

also, I think you'll do better than your tests, when you fill it up, w/precooled foods.

 

[Apex]

Friend at the marina suggested using Pelican coolers....a step above the 5day igloos by a fair margin.