I am posting a few days in SW FL with moderate temps and outdoor dew points. Low/no cooling load 3 ton a/c, Ultra-Aire 90 dehumidifier maintains 50%RH when the doors are closed. When the indoor dew point is above the outdoor dew point, the home is occupied and dehu is not operating. When the indoor dew point is below outdoor dew point, the dehu and a/c are removing moisture. Windy weather this week with 60-90 cfm of fresh air.
The 3 ton a/c is slightly oversized deals well with t-stat setup when the home is not occupied. With 10+ mph wind, the home gets and air change in 4-5 hours. During clam winds, the house needs make-up ventilation.
The main point here is that adding a dehumidifier to a home make Maintaining <50%RH for comfort and health.
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Regards TB

11 14 12 FL house data fin.pdf