I just ran my evaporative cooler for the first time and there is an unpleasant odor.

Our unique design and manufacturing technique, together with our superior materials, enable our products to perform efficiently within a wide range of conditions. When installed correctly, our evaporative media products allow complete molecular evaporation of water ensuring a pure, clean stream of air. When new, it is possible that a small amount of aromatic molecules may evaporate along with the water molecules, which could be detected as a slight smell. This scent lessens in time. Our product does not, in any way, allow harmful chemicals to be evaporated into the air stream.