Schroder2 arm near a window +heater/airconditioner

YES. M-U-C-H better.

Move the stereo.

Tarsando - I wish that were an option, but apartments here are rather small and thats the only space for a rack.

same here, I have also placed a plant next to my rack between the window and the TT....

Hello emailists,
No, weather conditions might affect your mood, but certainly not the arm. I would still advise against setting up your turntable close to an air conditioner as most cartridges are sensitive to variations in humidity and temperature. Rapid changes of either will affect the performance of your vinyl rig.
Hi Thomas! Do you never grow tired of shouting the same old thing? ;-)

Have a great weekend,

Frank Schröder