nikdfish
Veteran Member
In the unfinished basement (a walk-out) which is about 900 square feet & originally not part of the heated envelope. It really hasn't caused a noticeable difference, pretty much about like running a dehumidifier (which is another side effect). You need a drain option for the moisture it removes from the air, I added an elbow (had a plumber do it, anyway) connected to the main stack to let a gravity flow handle it. I added a vent & return to the basement space mainly to get some cooling during summer (my amateur radio gear is set up down there) & I do get a bit of heating that way as well (roughly a 12"x4" vent in the middle of the space & 12"x8" return above my radio desk). Our heating is primarily via heat pump w/propane backup. We have tended to use only about 50 gallons or so of propane a year (prior to adding the propane fueled generator last summer) so any "stolen heat" is generally coming from another heat pump.
Nick
Nick