Abstract: The humidifier includes a humidifying member, a storage water tank, a circulating water tank, a residual water tank, a supply pump configured to supply water accommodated in the storage water tank to the circulating water tank, a circulating pump configured to supply water accommodated in the circulating water tank to the humidifying member. A fan configured to blow air toward the humidifying member and thereby cause water evaporated to be discharged outside the humidifier, an internal pipe configured to form a flow passage through which water not evaporated by the humidifying member is recovered to the circulating water tank, a drainage member configured to selectively discharge water accommodated in the circulating water tank to the residual water tank, and a controller configured to operate the humidifier in humidity mode based on the water level in the storage water tank.

Abstract: The humidifier includes a humidifying member, a storage water tank, a circulating water tank, a residual water tank, a supply pump configured to supply water accommodated in the storage water tank to the circulating water tank, a circulating pump configured to supply water accommodated in the circulating water tank to the humidifying member. A fan configured to blow air toward the humidifying member and thereby cause water evaporated to be discharged outside the humidifier, an internal pipe configured to form a flow passage through which water not evaporated by the humidifying member is recovered to the circulating water tank, a drainage member configured to selectively discharge water accommodated in the circulating water tank to the residual water tank, and a controller configured to operate the humidifier in humidity mode based on the water level in the storage water tank.

Abstract: A method comprising detecting an indoor carbon dioxide level; detecting an outdoor fine dust level; driving an air supply fan and an exhaust fan such that an air supply amount of the air supply fan is greater than an exhaust amount of the exhaust fan based on detected indoor carbon dioxide level and outdoor fine dust level; and performing a first indoor pressure control of detecting an indoor pressure and controlling the air supply fan and the exhaust fan. In the indoor pressure control, based on the detected indoor pressure being less than a first set value, a number of revolutions per minute of the exhaust fan is controlled to be decreased, and based on the detected indoor pressure is greater than or equal to a second set value greater than the first set value, the number of revolutions per minute of the exhaust fan is controlled to be increased.

Abstract: A humidifier includes a storage water tank configured to accommodate a predetermined amount of water; a circulation water tank having a smaller capacity than the storage water tank and including a circulation low water level sensor; a supply pump configured to supply water from the storage water tank to the circulation water tank; a circulation pump configured to supply water from the circulation water tank to a humidifying member; a residual water tank configured to accommodate water discharged from the circulation water tank; a drainage member disposed between the circulation water tank and the residual water tank selectively to discharge water from the circulation water tank to the residual water tank and a processor configured to control the drainage member to discharge water from the circulation water tank to the residual water tank when a low water level signal is received from the circulation low water level sensor.

Abstract: An integrated air conditioning system includes a ventilation device comprising a first temperature sensor, a first humidity sensor, and a heat exchanger installed on the inlet flow path. An indoor unit configured to discharge heat-exchanged air into an indoor space. An outdoor unit configured to supply a refrigerant to the ventilation device and the indoor unit. A controller connected to the ventilation device, the indoor unit, and the outdoor unit. The controller configured to obtain an indoor temperature from the first temperature or the second temperature sensor. The controller configured to obtain indoor humidity from the first humidity sensor or the second humidity sensor and configured to control at least one of the ventilation device and the indoor unit based on the indoor temperature and the indoor humidity.

Abstract: An integrated air conditioning system includes an outdoor unit, an indoor unit, and a ventilation device. The ventilation device includes a housing including an inlet flow path, and an outlet flow path, a total heat exchanger in which air flowing through the inlet flow path and air flowing through the outlet flow path exchange heat with each other, a first heat exchanger disposed on the inlet flow path to receive a refrigerant from the outdoor unit, a second heat exchanger disposed upstream of the first heat exchanger on the inlet flow path and connected to the first heat exchanger to be supplied with refrigerant discharged from the first heat exchanger, a first expansion device to expand the refrigerant supplied to the first heat exchanger from the outdoor unit, and a second expansion device to expand the refrigerant discharged from the first heat exchanger and supplied to the second heat exchanger.

Abstract: The humidifier includes a humidifying member, a storage water tank, a circulating water tank, a residual water tank, a supply pump configured to supply water accommodated in the storage water tank to the circulating water tank, a circulating pump configured to supply water accommodated in the circulating water tank to the humidifying member. A fan configured to blow air toward the humidifying member and thereby cause water evaporated to be discharged outside the humidifier, an internal pipe configured to form a flow passage through which water not evaporated by the humidifying member is recovered to the circulating water tank, a drainage member configured to selectively discharge water accommodated in the circulating water tank to the residual water tank, and a controller configured to operate the humidifier in humidity mode based on the water level in the storage water tank.

Abstract: A humidifier includes a storage water tank configured to accommodate a predetermined amount of water; a circulation water tank having a smaller capacity than the storage water tank and including a circulation low water level sensor; a supply pump configured to supply water from the storage water tank to the circulation water tank; a circulation pump configured to supply water from the circulation water tank to a humidifying member; a residual water tank configured to accommodate water discharged from the circulation water tank; a drainage member disposed between the circulation water tank and the residual water tank selectively to discharge water from the circulation water tank to the residual water tank and a processor configured to control the drainage member to discharge water from the circulation water tank to the residual water tank when a low water level signal is received from the circulation low water level sensor.