Questions about temperatures in Sun Room

[Zoren]

Hello! members, sorry I haven't been around for a long time, I have been having problems with all my orchid growing. I've been growing my orchids in my Sun Room in South Florida facing SW for about 5 years with very little good results. My problem has always been to much heat in the room. I know I the answer was an AC, but, I live in a condo and putting in air conditions is 'against condo law' (similar to 'trump', sorry I digress). So I had to get permission to put in a portable AC with window kit, it took months and a lot of 'politics' to get permission to put in the AC. Now it's in. In reading about temperature control I keep reading that there should be a 10-15 degree difference between day and night temperature to get the best results in growing 'warm' to 'intermediate' orchids. My question is should I have the AC keep the room around 80 to 85 degrees during the day and at night put the temperature at about 75 degree. If I put the temperature below 70 degrees my electric bills will be 'TWO OVER THE TOP'. So I think that I can put the AC at 85 degrees Day time and 75 degrees at night. Does my plan seem to be correct. Keep in mind the AC will work most efficiently and work at maximum based on Ambient Temperature. I'm open to all suggestions and practical answers to my problems!