First, I'm not a Dynacool Tech,
* I remember having one as a kid. You need to fill it with water for the circulator (pump) to work and drip water over a filter that has a fan blowing through it. The water evaporates and cools the air as it flows through (It also increases the humidity).
* here is a Honewell manual. Check out page 12. There should be enough information to get you started.
* Final, Check your warranty and call for service. (though I can't seem to locate a current phone # or web site. May have gone under or bought out.)
* about upgrading to a newer model. There have been many changes to Air conditioning and heating. Many are more efficient and built with newer technology as this evaporative cooling method was used in the 1940's and popular in the 1970's. Check out your local stores and show rooms. Also check Home Depot and Lowe's for home air conditioners