tbates37

My unit is a 3 year old carrier. The air handler in located in the crawl space which has a concrete floor. All foundation vent are open. The humidity here in NC is high. The problem started about six months ago. The problem is that the return air plenum which is sheet metal with insulation wrapped around it has been constantly dripping with condensation. One company recommended that I close all the foundation vents and another says I should buy a dehumidifier. May I have some comments on these two solutions, please.