For those more familiar with hvac systems in Houston, Texas with house built in 1998, my daughter says at nite occasionally she hears drips in attic. I know the secondary drain to the a/c evap. coils are near her window but I am not using the a/c system now. I am using the house furnace (heater) at nite and wonder if it has any condensation that goes out the drain pipe??? I went in attic saw no leaks, water or sounds. I even checked the ceilings too. I think she hears something just not sure what. She says it only seems to appear at nite so I'm thinking now a critter tho I saw no signs of holes in the side of house or sounds in attic. I know it could be also on the roof instead of the attic. I realize that I need to go into the attic when she hears the sound.
I guess what I'm asking is do heaters throw off water from condensation under normal operating conditions?