Install ventilation to dry out a damp crawl space by placing a dehumidifier and a heat source in the area. The dehumidifier helps to dry out the damp, and the heat source keeps the crawl space dry.
Install a dehumidification system in a crawl space by first making sure you have the proper drain hookup. Install plastic on the bottom of the crawl space, and place a dehumidifier in the center of the area with a hose connected to the drain. Use an extension cord if necessary to hook the dehumidifier up to a power source. Place fans around the crawl space to help remove extra moisture.
Once the dehumidifier is in place, add a heat source such as a small electric baseboard heater to the crawl space to help keep the area dry. In some cases adding an exhaust fan can help to ventilate crawl spaces, but it depends on the humidity of the area and how well-sealed the crawl space is.
Before installing ventilation, remove all standing water by pumping it out. While you do this, remove all wet materials and debris. Do not add a dehumidifier to an area contaminated with mold, as this can ruin the dehumidifier and make the mold infestation worse.