water-to-water heat exchanger

例句：

1. 1. The new water-to-air heat exchanger significantly improves the efficiency of heating systems.
   新的水-空气热交换器显著提高了供热系统的效率。
2. 2.The design of this water-to-oil heat exchanger is optimized for maximum heat transfer.
   这种水-油热交换器的设计旨在实现最大的热量传递。
3. 3.The water-to-air heat exchanger in the cooling system is responsible for removing excess heat from the air.
   冷却系统中的水-空气热交换器负责去除空气中的多余热量。