[alfredo]

On a boat Sovran 39 do I need to run the air 24/7 or just the humidifier the boat is in south florida

[trit21]

I run my AC in dehumid mode during the winter but during the hot summer months I run in 24/7. Increase temp to 78 or so and let it run. Just make sure all the plumbing is good, no cracks, and the strainer needs to be cleaned on a very regular time frame, like every other weekend or so depending on water quality. YOu will also need to make sure your shower sump is on all the time assuming your AC condensate drain goes to the shower sump like mine. Clean the shower sump at least once a year, maybe every 6 months to avoid build up and a stuck switch or gummed up pump. I replace my shower sump pump, 800 GPH, once a year regardless. Cheap insurance IMO. 

[Maxwell]

I would at least keep the climate controlled all of the time to keep moisture down...  The units topside we only used when we were onboard...

[DavidB]

I am in South Florida also.  I set my main salon and forward cabin to 78 degrees and the helm at 80 degrees when I am not at the boat.  The AC will remove the extra moisture and keep everything reasonable.  I check/clean my AC strainers every other week in the summer and once a month in the winter.