Jun 13 '23
Making a can chiller from a $10 fridge
Backstory: I bought a mini-fridge can cooler from Wal-Mart that was on clearance for about $10. It kept cans at about ~45F but wasn't really worth keeping around. I wanted the lighted LED mirror/door for a different project and was disassembling it at which point I removed the main chiller.
After googling some part numbers and reading Wikipedia articles I learned that the chiller was based on a Peltier Cell (Wikipedia) which is a solid state component that moves heat from one of its flat sides to the opposite when a voltage is applied.
I found the cell in the chiller was able to take a higher voltage (which results in more heat being moved resulting in a lower temperature) so I connected it to an appropriate power supply (24V rather than 12V). I also connected a better fan to to the cell and added insulation around it.
This resulted in temperatures as low as -34F, much lower than the ~45F it was previously keeping cans.
Placing a single can of soda on the cool surface froze the can in about an hour and a half, at which point the soda burst and I realized maybe this wasn't the best idea.