I was looking at the electric clothes drier in my basement last night and wondering, where does the air come from that makes up for the drier's vented air? A minute later I was working by the hole in the foundation that the lineset comes in, and I could feel the cool breeze. That answers that question.
The funny thing is, I've been caulking around windows and siding, checking doors and sealing cracks, doing everything to keep the conditioned air in and the outside air out, and in another thread:
it was strongly suggested I need more air exchanges. OK, I can buy that. The question is, how?
Ideally, I would like my fresh air solution to:
a.) Not negatively impact my energy bill, at least not much. A small amount is OK.
b.) Be filtered air. Humidity is OK (see other thread), but outside allergens are not welcome.
c.) Passive solutions are preferred, but I'll consider anything.