It must be different outside the US because I am not sure I've ever heard someone say "air conditioner" when talking about heating. Yes, they are typically the same system (HVAC; Heating Ventilation & Air Conditioning), but at least in my entire life experience, everyone says "air conditioner" when it's warm out and "heater" when it's cold out. Never have I heard, "turn up the air conditioner" when it's cold and "turn down the air conditioner" when it's warm. Everyone always says "up" relative to the temperature, so "turn up the air conditioner" when it's warm and "turn up the heater" when it's cold.
As for the butter thing... Yeah, I gotta think that's just a translational thing or the Japanese really do refer to smaller pieces as "sticks." Drinking a whole stick of butter would be disgusting beyond all belief, in addition to being incredibly unhealthy.