Crawl Space Dehumidifiers not Working

Ryalis

Junior Member
Jun 27, 2016
2
0
0
My place in Wisconsin has about a four foot crawl with a dirt floor. The floor has loose sheets of plastic scattered about. There are no vents to the outdoors, so the crawl is sealed from outside air. The crawl maintains all the mechanicals, furnace and water heater. There is a blower down there moving air 24/7. The house was built in the 40's and the crawl is about 800 sq ft. and probably maintains temperatures in the range of low 70's.

My problem is I can't get the new dehumidifier to work. First, I tried a Frigidaire 50 pt unit. It is rated to operate in temps as low as 41 deg. Connected the discharge hose to a condensate pump. I ran the unit for about four days and could not get the humidity to go below 75. The unit was set at 40. There is nothing blocking the air flow to the unit. I wasn't sure it was working so I removed the discharge hose and waited to see if the bucket would accumulate water - not a drop. So, I figured I got a bad unit and replaced it with a GE 50 Pt.

In regard to the GE replacement, while connecting the discharge hose to the condensate pump, I noticed in a short time there were signs of water being generated. Came back couple days later and found humidity level was at about 75, unit set at 40. Removed hose and let water collect into bucket overnight- not a drop.

Placed the first unit, Frigidaire in the garage to test before dumping it, and found the bucket half filled with water after only a few hours. The temps in the garage were in the 80's and high humidity. So, I guess the Frigidaire is good. Any advice is greatly appreciated.
 
Last edited:

Blain

Lifer
Oct 9, 1999
23,643
3
81
I would make every effort to seal the crawl space from the earth beneath, especially given the fact that there are no vents. Seal it and you can keep it dry.
Get a wireless temp/humidity gauge to keep track of the humidity levels, without going under the house.