No "argument" intended, but I just wanted to say I think it's more a case of "different strokes for different folks". I live by myself, there is no "problem with my system", and I would
SUFFOCATE at 78 (that's just two degrees below 80!) And "normal, neutral room temperature" for me is between 65 and 68! So that's what I keep things at. That way, the air still runs late at night in the summer instead of going off for long period of time at night, which would make things feel stuffy and muggy. At 68 degrees, not only am I always comfortable, but I sometimes feel that faint trace of a slight chill in the air when the air runs, which I
love so much. My AC is doing it's job of removing every last bit of heat and humidity from the air, and making my living space live up to my ideal of being
cool, dry, and cave-like! Whenever I visit friends or relatives who keep the air close to 80, I acutely feel an uncomfortable sense of stuffy mugginess. And their ACs are not broken, nor or there too many people in the house!
Then again, 78 is uncomfortable for me as an outdoor temperature as well, (my ideal comfort zone is between 40 and 70), and I love the 40's, and I can be perfectly comfy in just shorts and a t-shirt down to around 50 degrees if there is no severe wind chill! The cost of cooling my living space in the summer is balanced out by me never running heat in the winter, though. I'll let the air temperature drop into the low 60's and even 50's during those long-awaited cold snaps and marvel at the fact that I can get that nice, comfy, unhumid
CHILL in the air that I love so much without having to pay for it!
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(Of course, the air conditioning still runs on hot days during the winter)
I've been called an "Eskimo", "Snow Miser", "Mr. Freeze", and told I have "thick blood". And I'm slightly lighter than the average recommended body weight for my height, and am from (and always lived in) the south! But in my world,
cold rules and heat drools!
Which explains why I
love the parks in the winter! I'm the person loving the cool air in shorts and a t-shirt when it's only 55 degrees, and I'm perfectly comfortable, while most Floridians are dressed as if they are at the Arctic circle!
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The only time I'm uncomfortable in the winter is when I go into a shop, restaurant, or interior attraction and they have the bloody, stupid, heaters blasting hot air and making me feel stuffy and uncomfortable. Which is all the more reason I stick to shorts and a t-shirt as much as possible. Think of how even more uncomfortable those heated buildings would be with long pants and a sweater/jacket!