No AC at my place either. I'm currently at 75 degrees and 30% humidity with a fan pulling in cool outside air and another fan in a different room pushing out hot inside air. Later this morning when I go to bed I should be down to 25% humidity. I close the house up during the hot part of the day, and can get up to 45% before it cools down outside and I get the fans going again.

As for the OP's question, it depends on how much outside air the AC is pulling in and the input and output temperatures of the unit. I would have to get the book from my college HVAC elective out to give a more definite answer. It would have something to do with the AC output temperature (lower pulls out more water) and the in house process (load IOW). I can imagine low load in relation to the unit's capacity resulting in poor humidity mitigation.

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Whoever said there's nothing more expensive than a cheap Mercedes never had a cheap Jaguar.

83 300D Turbo with manual conversion, early W126 vented front rotors and H4 headlights 401,xxx miles
08 Suzuki GSX-R600 M4 Slip-on 26,xxx miles
88 Jaguar XJS V12 94,xxx miles. Work in progress.
99 Mazda Miata 183,xxx miles.