AdvertisementHot, Hotter, Hottest: Nation Sweats It OutJuly 20, 2011NPR Staff and WiresfacebookEmailEric Rebolledo, a repairman for AllTemp heating and air conditioning in Chicago, works on an air-conditioning unit on the roof of an apartment building. "I don't remember it being this hot for at least 10 years that I can recall," he says. "This is unusual, man, so it's gonna create some havoc with the air-conditioning systems." (David Schaper /NPR)