網上看到有說法是普通製冷空調與熱泵的區別僅在於熱泵有個翻轉閥門，可轉換熱量移動方向

真要是區別隻這麽少，熱泵的價格不應該比單冷空調貴很多才是

Heat Pumps are just that; units that pump heat, from either outdoors to indoors (in the winter) or from indoors to outdoors (in the summer). Your ordinary air conditioner is a heat pump, but that works in only one direction (it moves heat from indoors to outside). Heat pumps include a reversing valve, so they can move heat either direction.

While very similar to air conditioners, heat pumps are more complex and require special tools and training.