I wish
I wish that I had some positive info to offer you, but I don't. As I continue to think about it, it seems that what we're after is "fog" rather than "steam". The professional consultants will tell you that if it's moist and warm, then it's steam and you should be happy. They glaze-over and spout babble when you mention "visible vapor". There are little room vaporizers that make cold vapor... the whole thing remains a mystery to me. The steam unit is not very complex, it's basically a pot of boiling water with a vent into the steam room. Frustratingly we had one in Colorado that worked great (LOTS of visible vapor - you basically couldn't see your hand at the end of your outstretched arm, you certainly couldn't make out the walls of the steam room), as well as in California (albeit the one in California was only bathtub-sized), so it doesn't really seem that elevation (different boiling temp.) has much to do with it, also the climate in Colorado was "semi-arid", as is the climate here. Good luck. My experience has been that you're on your own. If you come up with anything, let me know. Leaving the door open a bit often increases the amount of vapor for a couple of minutes...