Heater/Air Vents

[ces797]

Question about vents in the home. Usually vents are placed next to windows to counteract the loss of heat/cold. So what that in mind pretty much every useable window in my house is located next to a heater/air vent. Is the major problem with these the temperatures they inflict? Anyone growing near heater or ac vents without any problems? How close it to close to a vent? I just started my orchid collection and I have had my window's open without running heat or air and I'm wondering what problems I may face when I have to start running the A/C.

Thanks for your help
Curtis