Crap! forgot my email, sorry about that! I'm not a 100% sure, but I have used AC water to cool the root systems, (Pots) on a very hot tar/rock roof, I'm 90% sure the water was getting into the plant on windy days, it didn't seem to hurt them. All though the water over time does have scale, or calcium type build up, over long periods of time. My tomatoes turned out fine, I got 30 or 40 out of the plant. I did fertilize them regularly Let me know, if someone knows for sure, I may try it myself. I work around very large units and have contemplated this question myself.