Upvoting for visibility, but this seems insane and impossible to me. When I take a cold shower, I can feel the water stealing the heat from my back, because it's warmer when it hits my legs. It's crazy.
It's definitely taking heat away, for me, and I would die if I tried to take a hot shower on a hot day.
I start with a warm shower, like normal, then slowly turn it down until it's nice and cool, almost cold. But not ice cold. Feel way better afterwards.
Window units are the best bang for the buck. Don't worry about expensive ones, $100 goes a LONG way to cooling one bedroom. And it's cheaper than doing the whole house.
We have a big in wall unit in our apartment that can do the whole living space, but we hardly ever run it. We just run the bedroom one, set to like 70-75f, just to take the humidity out and chill it down a bit. A nice place to go cool down if you get hot while doing things around the house. We don't run it when we're not home, because even the cheapest Menards special can cool the room down in minutes, and it's cheaper to not run it when we don't need it.
Beware of the units with the hose... You're paying more, and trading the convenience of not lugging a big unit into the window (small ones really aren't that bad), for the inconvenience of having to dump the water (unless you pay more for one that can pump it out the window).
But by far the worst thing about the hose units, if they only have one exhaust hose, and no return hose? They are less efficient, because they create negative pressure in your house that sucks hot air in through every crack.
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