Steve,
Open the machine and on the top of the vending rack on the left side near the bolt that holds the rack in you should find a serial number. Generally the first two numbers in the SN are the year it was made. At least that is my understanding.
![drinking](http://soda-machines.com/discussions/Smileys/smc/drinking.gif)
Tim
![drinking](http://soda-machines.com/discussions/Smileys/smc/drinking.gif)