Can I use this unit for a 30,000 gal pool in Plantation, Fl? There is no screen enclosure and has full sun.

Typically it is suggested to use the HE150 up to about 20 - 25K gallons. Other factors like desired temp and if heating in the colder months is in high demand. It might be suggested to use (2) HE110 units since it will provide more heat and provide backup if one goes down as this seems to be a commercial application.... If you have any further questions, please feel free to give us a call! Thanks.