| 摘要 |
<P>PROBLEM TO BE SOLVED: To provide a heat exchanging device having smaller pressure loss of water and less elution of scale components and good heat exchanging performance for promoting heat transfer without using other parts as heat transfer promoters, and to provide a heat pump water heater using the same. <P>SOLUTION: The heat exchanging device comprises a first heat exchanger tube 81 in which first fluid flows and a second heat exchanger tube 90 in which second fluid flows, arranged in the first heat exchanger tube 81. The second exchanger tube 90 is formed by spirally twisting a plurality of heat exchanger tubes 91, 92. The heat exchanger tubes 91, 92 are in a double tube structure consisting of inner tubes 911, 921 and outer tubes 912, 922, respectively. <P>COPYRIGHT: (C)2005,JPO&NCIPI |
