Here in Southern California, Halloween often falls during one of the last heat waves of the year. Recently, when trying to devise a dry ice fogger, I accidentally created a way to not only produce some spooky atmosphere for any parties or get-togethers, but also to cool things down with some dry ice air conditioning.
My original idea was to force fan air over a cloud of dry ice fog, spreading it through a room. As I developed the project, I hit a few snags and realized the device couldn’t do all things at all times was best utilized for single uses, one at a time.
Step 1 - Problem Solving
The first thing I needed was a way to insulate the dry ice, so I bought a simple cooler. I liked the cylindrical shape, because it would fit with the fan I planned on mounting into the lid. That was the next thing to find: the correct size fan to fill the top. Once I had these major components in place, it was time to start building.
Step 2 - The Holes
I measured the protrusion at the front of the fan and marked a circle of the same size on the top of the cooler lid. Using a jigsaw, I cut the hole out so the fan fit perfectly while aiming down into the cooler. A few minutes with some duct tape took care of any gaps in the fit and completed the seal.
Now it was time for the air outlets. I drilled holes using a hole saw toward the top and the bottom of the cooler, not quite sure which would be best for airflow. I set step-down threaded PVC pipe fittings into these holes and caulked any gaps. It turned out that the bottom vents were optimal for the fogging, so I plugged the top outlets.
Step 3 - Handle With Care
My local supermarket was the easiest source for dry ice. Use extreme caution when working with this material. The surface temperature is around minus 109 degrees F and will injure any exposed skin. Never, ever put it in your mouth. Make sure any children are supervised near it. Heavy gloves, a slow pace, and attention to detail are necessary when dealing with dry ice.
Also, be sure you’re doing this project in a well ventilated area. Dry ice is condensed carbon dioxide and shouldn’t be used in enclosed spaces like cars or sealed rooms. It can fill up an inclosed space and suffocate you.
Step 4 - Fire Up the Cooler
I unwrapped my dry ice and placed it at the bottom of the cooler. Around 5 pounds was plenty to create the effect I wanted for quite a long time. In order to get dry ice to turn to fog, just add water. Hot water works best to create a thick blanket of spooky white mist on the floor.
As I poured the hot water on the dry ice I could hear the sizzle of the material turning directly to gas and skipping the liquid stage. Soon voluminous ribbons of fog were spilling out of the lower outlets. The haze clung to the floor and swished and eddied if anyone walked through it.
I turned on the fan, thinking it would just send more of the fog further into the room. The rapid air, however, only dissipated the fog. Lesson learned: when the haze is wanted, leave the fan off. But if the Halloween festivities turn too hot, you can get the fan cranking and send waves of cool air throughout a space.
You can also attach vacuum cleaner hoses to the outlets to direct the fog where you want it.
So the modified cooler now serves a double Halloween purpose: it can deliver special effects or air conditioning.