It cannot be overstated how important it is to know how to pre-chill your cooler, and to actually do it every time you use your cooler. Bring your cooler inside the house 12–24 hours before you pack it. Depending on the size of your cooler, you'll want to fill it with 10–20 pounds of sacrificial ice.
Pre-chilling your cooler overnight or a day before using it allows you to take all that heat out of the insulation. That way when you put your ice in, the insulation doesn't melt the ice and does it's job to keep out heat and keep your ice frozen.
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When you pre-cool a cooler, you bring its temperature closer to the intended food temperature goal, thereby not wasting energy cooling the cooler. When the better coolers are pre-cooled, they will substantially outperform a pre-cooled low-end cooler.