I don't know how hot it gets in Hawaii, but I have a friend here in N. TX who also has a chinchilla with no A/C. She keeps a fan on in the room (it still helps, even tho your baby doesn't perspire, becuase the fan will still move the hot air off your little guy - your car radiator does not sweat, either, but your car's fan still cools it off) and gives him his volcanic ash once a day, and he seems to do fine. It normally stay 95-105 from May to September here to give you a comparison.