it says in the description that it doesn’t work in very dry conditions. what exactly are those conditions?
Sunny?
Try think of any weather condition that doesn’t revolve with much water, or the opposite eg Rain/Drizzle.
Actually, I think it works with temperature, anything above warm wont get you water.
EDIT: Forget about it, it seem to work everywhere: sunny days, hot temperatures, inside magma rifts while submerged in lava.
lol so i guess this combined with Joint Tortion Ratchet i can stop lugging water bottles around 
Ideally once we get biomes in (through the portal system, cold portals making cold areas, hot making hot, etc.) then it won’t work in desert biomes.
And candy portals, making icecream biomes.
Really should be called aero-condenser.
Also, it would work better in hotter environments. 50[sup]C[/sup] air with 10% relative humidity has about the same absolute humidity as 20[sup]C[/sup] with 50% or 10[sup]C[/sup] with 90% (source).