This is a stupid question I guess. I recently purchased a new home, and don't know too much about this stuff. How do I know if my air exchanger and humidifier is working? I have an Aeromatic 2000 air exchanger, and I General Aire humidifier. Both are attached to the furnace, and heat and cool appear to be working fine, but how do I really know if the exchanger and humidifier are working? There are no lights on these devices, and I never see any water in the drip pan or in the drain pipes. Should a lot of condensation be generated? Just want to make sure everything is working as it should.