I live in PR too and I found it easier to get a cool spot in the house that has the least things that will affect temp(windows, AC, water heaters, etc) so it wont get too hot, and use the UTH with the thermostat so it wont get too cold... you know here in PR although it can be 80-95F all year round the temp fluctuates more than a bit (atleast for me since i live in SJ)