A heat pump water heater comprising: a compressor configured to compress a refrigerant; a first water-refrigerant heat exchanger configured to exchange heat between the refrigerant and water; a second water-refrigerant heat exchanger configured to exchange heat between the refrigerant and water; refrigerant paths (10, 17, 18, 19, 20, 21) capable of forming a refrigerant circuit, the refrigerant circuit supplying the refrigerant compressed by the compressor to the first water-refrigerant heat exchanger, the refrigerant circuit supplying the refrigerant that has passed through the first water-refrigerant heat exchanger to the second water-refrigerant heat exchanger; and water channels including a flow channel, the flow channel leading hot water that has passed through the second water-refrigerant heat exchanger to the first water-refrigerant heat exchanger, the heat pump water heater being able to perform a heating operation, the hot water heated in the second water-refrigerant heat exchanger being fed to the first water-refrigerant heat exchanger in the heating operation, the hot water further heated in the first water-refrigerant heat exchanger being supplied to a downstream side of the water channels in the heating operation, the first water-refrigerant heat exchanger being able to be replaced without replacing the second water-refrigerant heat exchanger, characterized in that the heat pump water heater further comprises a plurality of chambers (32, 33), wherein the first water-refrigerant heat exchanger and the second water-refrigerant heat exchanger are disposed in different ones of the chambers (32, 33), wherein the first water-refrigerant heat exchanger is disposed inside the chamber in which the compressor is disposed, and wherein the second water-refrigerant heat exchanger is disposed inside the chamber in which an evaporator configured to evaporate the refrigerant is disposed. a compressor configured to compress a refrigerant; a first water-refrigerant heat exchanger configured to exchange heat between the refrigerant and water; a second water-refrigerant heat exchanger configured to exchange heat between the refrigerant and water; refrigerant paths (10, 17, 18, 19, 20, 21) capable of forming a refrigerant circuit, the refrigerant circuit supplying the refrigerant compressed by the compressor to the first water-refrigerant heat exchanger, the refrigerant circuit supplying the refrigerant that has passed through the first water-refrigerant heat exchanger to the second water-refrigerant heat exchanger; and water channels including a flow channel, the flow channel leading hot water that has passed through the second water-refrigerant heat exchanger to the first water-refrigerant heat exchanger, the heat pump water heater being able to perform a heating operation, the hot water heated in the second water-refrigerant heat exchanger being fed to the first water-refrigerant heat exchanger in the heating operation, the hot water further heated in the first water-refrigerant heat exchanger being supplied to a downstream side of the water channels in the heating operation, the first water-refrigerant heat exchanger being able to be replaced without replacing the second water-refrigerant heat exchanger, characterized in that the heat pump water heater further comprises a plurality of chambers (32, 33), wherein the first water-refrigerant heat exchanger and the second water-refrigerant heat exchanger are disposed in different ones of the chambers (32, 33), wherein the first water-refrigerant heat exchanger is disposed inside the chamber in which the compressor is disposed, and wherein the second water-refrigerant heat exchanger is disposed inside the chamber in which an evaporator configured to evaporate the refrigerant is disposed.