I purchased two of these last fall from Sam's and I did vent them. I believe they will work fine until I can someday find something in Lithium that I can afford.
Bob
First Post on Purchase of Trailer: http://www.tnttt.com/viewtopic.php?f=42&t=60722 Hot water infloor and radiator heating project:[url]http://www.tnttt.com/posting.php?mode=reply&f=54&t=62327[/