I installed a dehumidifier in my crawlspace this weekend. Crawlspace floor is 20x30 feet, and average 4 feet tall, so 2400 cubic feet. Pressure, thankfully, was stable at 29.9 inches through out the sampling period. When I started the dehumidifier, crawlspace temp was 64 degrees F, RH was 47 %. 18 hours later, 29.9 inches, 64 degrees, 40% RH. I recovered 6.5 pints of condensate from the dehumidifier. I thought would just convert to absolute humidity for start/ stop to get a feel for how much water I am sucking out the poured concrete walls of the crawlspace. It is starting to look like maybe working in specific humidity might make more sense.... Help, help, I are well and truly stuck.