I understand that I'd need to "empty" the thermos often, but would this theoretically work?
Like, ok, here is what happens with an AC. A condenser unit pressurizes gas that gets cold and hot. Fan moves air over the cold part that blows into the dwelling. Fan moves over the hot part where air is expelled and is vented. This air is isolated. Condensation happens in all of this and is used to further cool the hot section and that is collected and recirculated in some models. In others it is actively drained.
This is an oversimplification you don't need to correct me also, nerds.
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You must be doing pretty well in life to be wondering about venting an AC into a thermos.
I feel so happy for you :)
Yes --- like almost continuously.