HEAT EXCHANGER AND HEAT SOURCE DEVICE

A heat exchanger disposed on a downstream side of a gas flow passage of combustion exhaust gas ejected from a burner comprising a plurality of heat exchange units stacked in a gas flow passage direction of the combustion exhaust gas, an inlet pipe, and an outlet pipe, wherein the inlet pipe and the outlet pipe are provided so as to protrude from a most downstream heat exchange unit located on a most downstream side of the gas flow passage of the combustion exhaust gas toward the downstream side of the gas flow passage of the combustion exhaust gas.