Evacool vs Techni Ice esky

[Andy M]

A trick I have learned with any esky to keep ice longer is to put a hessian bag over the ice in the esky (seems to reduce the amount of cold lost each time you open the esky for a coldie as the majority of ice stays covered). I purchased a blue Techni ice 70L a few years ago and have been very happy with it - I agree with everyone else - get a white or yellow one for preference - you can feel the heat on the blue ones when they sit in the sun. I did however carry out a test with crushed ice when I first got it - still had ice after 10 days under the house in the shade -good enough for me. Countermeasure for sitting in the sun is to put another wet hessian bag on the lid - works well (got them at the local produce store). I have just ordered 2 x 60 L white Technis for seat boxes in my new (secondhand) 5m tinnie (padded seats will be fitted to the tops) - one for dry storage & one for food & drinks. Fiberglass eskies are great - just don't handle the bumps as well as the poly ones. Hope this helps

[chisel]

Just Chips, I agree with your points except for leaving the bung open.

I could be wrong but I think there are two reasons it's wrong. Firstly because the cold air inside will exchange with the hot air outside in a slow but inevitable process through the bunghole.

Secondly and more importantly, I think that the slurry represents a 'thermal mass' that resists heating... Ie the warm air that comes in and also the esky walls, are bleeding heat into the esky contents, but if there is a slurry in there then the temperature rise is spread across more mass and hence is a lower rise.

Also the cold air that's in there is exchanged to some extent with the outside air by opening the lid. But if instead some of that airspace is occupied by water slurry them it doesnt get exchanged.... less cold is lost.

That's my two cents... I could be wrong.

Agreed
As long as there is some ice in the water then the water will be freezing cold - just above 0 degrees. Why replace freezing cold water with warm air?
I always leave as much water as possible in there although it means you can only have truly waterproof things in the esky once the water builds up.

[GBC]

Its called the law of thermal efficiency, from the first law of thermodynamics. Big name states 'you can't get more cooling energy than what you put in, and once it's gone, it's gone'.
Water stays cooler longer than air due to its mass.
If you let out water that's cooler than the ambient temp, you are letting out cooling efficiency.
If you want to keep it cooler longer, add salt to the water and turn it into a brine, but don't open the bung.
The laws of thermaldynamics however take no responsibility for the resulting mess.

[EMURUNNER]

I have a Evacool esky and have pulled it out of the boat on a sunday still with bait, beer and ice in it , placed it on the lawn and then decided to clean it out on the thursday after work. opened the lid expecting the worst, only to find cold beer still in ice and bait sill a bit frozen.
go the evacool

[darylive]

I have both polly and Eva Cool fibreglass. The poly boxes are a lot less efficient than the Evacool glass box and are more often used as boat seats and storage. As stated make sure you cool the box first, ideally ice overnight then pack fresh with ice the morning of the trip. A false floor to avoid the ice sitting in water helps. Rubber mat works. The other thing is freeze 2 litre containers and leave the ice in the container, it will last longer contained.