A:Answer There are better ways of controlling moisture in a crawl space. Exchanging the air in the space is what you should be looking into, which can be accomplished by installing an In-Line exhaust fan, such as you would use for Radon Gas mitigation. This accomplishes the task of removing odors as well, which a dehumidifier alone will not do. A competent contractor can help you with this work. I’ve employed this tactic for several clients, and all have been totally satisfied with the results, and I’ve had Zero callbacks for equipment failures because theses fans are made to run 24/7, quietly, and at low-cost! An avg. dehumidifier of the size you’re looking at will run you between $65 & $90 per month in electricity if used daily!!