>Is there any meaningful difference between a heat pump and an air conditioner, other than the direction the heat is pumped in? In terms of basic science, they

>Is there any meaningful difference between a heat pump and an air conditioner, other than the direction the heat is pumped in? In terms of basic science, they are the same principle so "air conditioner" is a type of "heat pump". But in terms of semantics that is understood by the general public for purposes of differentiating various HVAC equipment one can buy, a heat pump has an extra reversing valve to change the flow of refrigerant. A standard air conditioner doesn't have that extra feature. When folks casually say "heat pumps", they're talking about a HVAC equipment category and not general science principles.