An indirect-heating hot water apparatus is designed to correctly detect clogging in a secondary water circuit at low costs. A hot water apparatus is provided with: a primary water circuit in which water heated by absorbing heat from a refrigerant at a heat exchanger circulates; a secondary water circuit connected to the primary water circuit via a heat exchanger, in which water circulates; and a tank connected to the secondary water circuit, in which the water circulating in the secondary water circuit is stored. The hot water apparatus detects the temperature of the water circulating in the primary water circuit and the temperature of the water stored in the tank. When the temperature of the water circulating in the primary water circuit is at or above a first threshold and the temperature of the water stored in the tank is at or below a second threshold, the hot water apparatus issues a notification indicating that the secondary water circuit is clogged.