Heat exchanger

Abstract

Provided are a heat exchanger that does not impede downsizing and removes water in the heat absorbing pipe adequately with a simple configuration even when the reduction in diameter of the heat absorbing pipe is made. A heat exchangerin which heat absorbing pipesare disposed in a multi-tier arrangement within a casingwhich is the passage of combustion exhaust gas, both pipe endsof each of the heat absorbing pipesare connected respectively to two headersprovided on a side plateof the casingand water introduced from an external pipeto each of the heat absorbing pipesthrough the headeris heat-exchanged and heated by combustion exhaust gas. The pipe endsof the heat absorbing pipesare arranged at a predetermined vertical interval. A drainage platefor forming a drainage passage through which the water that has reached the pipe end openingsA of respective heat absorbing pipesis removed during drainage operation for the heat absorbing pipesis disposed in the headerdisposed on a lower side of the heat absorbing pipesso as to face a number of the pipe end openingsA vertically arranged in a state of continuous.