| 摘要 |
PROBLEM TO BE SOLVED: To ensure miniaturization of an apparatus without deteriorating heat exchange efficiency by providing a plurality of branch flow passages branched at an inlet side of a heat exchanger to a heated water circuit heat exchanger, and joinning the branch flow passages at an outlet from the heat exchanger or on the downstream side of the outlet. SOLUTION: Water to be heated flowing frown a supply pipe 16 into second and third water passage pipes 12, 13 of a sub-heat exchanger 1b absorbs latent heat and is raised in its temperature, which water to be heated passing through a second water passage pipe 12 flows into a main heat exchanger 1a and absorbs sensible heat and is hence raised in its temperature into high temperature hot water. Low temperature hot water passing through a third water passage pipe 13 is mixed with high temperature hot water flowing out from the main heat exchanger 1a to provide predetermined hot water. Hereby, an interval between the one branch flow passage and the other branch flow passage is more reduced than the radius of curvature of a bent pipe part 102. Accordingly, the entire of the heat exchanger is miniaturized compared with the prior art. |
