Air conditioning is reasonably rare in Germany. It's not unusual to go out to dinner and sweat profusely in the restaurant because the windows are only cranked open a small bit and of course there isn't an air conditioner unit. Why do you think you see so many people dining outside in the summer? Of course it's pleasant and makes for a good opportunity to get some staring in, but it's also because it's too darn hot inside the restaurant itself!
I have heard that it's a German belief that air conditioning is unhealthy. I always wondered why this was. Was there a concern about Leginonnaires' disease, which is an illness caused by bacteria in the air conditioning system? If that would be the case, the Germans should be more concerned about the illness-causing bacteria in their beloved hot tubs/spas as it's more common to get sick from that than from air conditioning.
Or, was it Germans' love/hate relationship with the beloved and most feared draft?
I had the opportunity to ask a German about this. She's married to an American and has lived in the US so she can see things from both perspectives. She said it's because Germans are concerned about getting a draft on the back of one's neck, or, da da da (cue the dramatic music), on one's kidneys (no joke, they have these wraps you can wear during the winter to avoid getting your kidneys cold). Some Germans believe that such a draft could make one sick and therefore people are extremely distrustful of air conditioning. Her mother always yelled at her never to sit on rocks or anything cold because she'd get a kidney infection. Kind of strange, eh?
I wonder where people came up with this idea. My theory is that maybe it came up after the War, when many people hadn't had proper nutrition for a long time and there was a lack of sanitation and other basic necessities until the country was stabilized. Perhaps people's immune systems were a lot weaker then and they did get sick more easily from drafts, cold, etc. The woman I was talking to wasn't sure where it came from, but in her case, it was handed down from her grandmother to her mother. She doesn't believe it herself but thinks it is strange to have to wear a sweater in the middle of summer with blasting air conditioning.
Who knows. I did mention that the LACK of a draft is really a negative thing in many German buildings. It is really unhealthy to have no air circulation in a building. For example, my friend went to a concert and some other attendees passed out because of the heat and the stale air. Air quality inside is often worse than it is outside because of toxins in the building materials, dust mites, and bacteria. Sunlight and air are the best ways to combat this.
Either way, I can say this: it's not enjoyable to roast on the days that it is hot in Germany. Maybe a trip to the Schwimbad is in order!