People report both very varied temperatures an humidity, as far as I have seen.
High moisture will - over time - damage your filament. Especially PLA sucks up a lot of moisture, and it will be difficult to print nice with. This can take months though, so if you keep your filament in an airtight box or sealed plastic bag when you're not using it, you should be good.
Low temperatures are not that important when you use a heated bed, but having your printer next to a window when there's a high difference in outside and inside temperature, can make one side of your printer colder than the other, and lead to warping.
High temperatures means you might have to add fans to cool down the electronics, which is a good idea for longevity anyway.
Airflow from an A/C unit can be difficult if it's very powerful, as it can make the bed struggle to keep the temperature stable, leading to warping.
Most of this things can be fixed by either increasing or lowering the print and/or bed temperature. Or you can make a cardboard shield to protect your printer.
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-Nudel
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