The auxiliary air conditioner units in my bus can be programmed to run a dehumidification cycle. Unfortunately, I can’t remember the brand or model right now, and the manuals are in the bus, which is packed for tomorrow’s trip. I’ll try to post the details first thing in the morning.
In the meantime, perhaps someone else can confirm if this applies to your situation. I’m having a bit of a “sometimer’s” moment right now.