First who told you this? That would suggest if you put it outside on a 78 degree day your beer will only get to 48, yet if you put it inside and had your thermostat on your AC set to 78 (where I set mine) it would be fine. Google up +outdoors and +kegerator and see what is available. Some kegerators certainly shouldn't be placed outdoors but there are some built for that use. I've shoved my cheap old Danby out on the deck for parties with no problem. However if it were extremely cold out I'd have problems.
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