Final answer:
The main difference between a heat pump and an air conditioner is that the heat pump can provide both heating and cooling by reversing its operation, while an air conditioner only cools.
Step-by-step explanation:
The major difference between a heat pump and an air conditioner is that a heat pump can reverse its operation to provide heating or cooling, whereas an air conditioner only cools. Both systems transfer heat from a cooler area to a warmer one, which requires work (W). Heat pumps are designed for heat transfer (Qh) into a warm environment such as a home during winter, and can switch to transfer heat from inside to outside during summer, effectively cooling the space.
Air conditioners, on the other hand, are primarily concerned with the coefficient of performance (COPref) related to how much energy they can remove (Qc) from an indoor environment to cool it, without the heating function.