An air-conditioning apparatus includes a refrigerant circuit in which a compressor, an indoor heat exchanger, a first expansion device, an outdoor heat exchanger, and a flow switching device are sequentially connected to each other; a hot gas bypass pipe coupling a discharge port of the compressor and the flow switching device to each other; and a controller. The outdoor heat exchanger includes an upper heat exchanger and a lower heat exchanger having passages in parallel with each other. The outdoor heat exchanger includes a plurality of hairpin pipes, which are part of a heat transfer pipe. When the upper heat exchanger is defrosted, all hairpin pipes that are located at a lowermost step of the upper heat exchanger are used as refrigerant inlets. When the lower heat exchanger is defrosted, all hairpin pipes that are located at an uppermost step of the lower heat exchanger are used as refrigerant inlets.

An indoor digital centralized controller system (DCCS) that is connected to a controller of an application system and accepts orders from the controller of the application system and controls at least one motor to work. The DCCS includes a power supply, a master control unit (MCU), a plurality of motor control modules, a programming port module, and an input interface. The power supply is configured to supply power for circuits. The MCU is connected to and communicates with the controller of the application system via the input interface. An outer computer is capable of rewriting control programs of the MCU via the programming port module. The MCU is connected to a motor via a motor control module. The motor includes a stator assembly, a rotor assembly, and a shell assembly. The stator assembly and the rotor assembly are coupled magnetically.

A total heat exchange device is disclosed, which includes: a fan directing air from an indoor exhaust port to an outdoor discharge port through an exhaust air path; a fan directing air from an outdoor suction port to an indoor intake port through an intake air path; and a heat exchange element for exchanging heat between the air passing through the exhaust air path and the air passing through the intake air path. The total heat exchange device further includes a temperature detection section for detecting an outdoor temperature and a control section configured to perform a heat exchange mode in which heat is exchanged between the air passing through the exhaust air path and the air passing through the intake air path or a defrosting mode in which frost on the heat exchange element is thawed, in accordance with the outdoor temperature detected by the temperature detection section.

A building ventilator to provide a supply of air into a building comprises an external inlet port and a separate external outlet port and an internal inlet port and a separate internal outlet port to allow respective airstreams to flow into and out of the ventilator respectively at an exterior and at an interior of the building; a heat exchanger mounted in the flow paths between the external and internal inlet and outlet ports. The ventilator is configured to drive an airflow from the external inlet port through the heat exchanger and out of the ventilator via the internal outlet port; and to drive an airflow from the internal inlet port through the heat exchanger and out of the ventilator via the external outlet port. The ventilator comprises a heating element mounted in the air flow path between the external inlet port and the heat exchanger.

A refrigeration cycle apparatus includes a refrigerant circuit including a compressor, an indoor heat exchanger, an expansion device, and an outdoor heat exchanger connected to each other via refrigerant pipes. The outdoor heat exchanger includes a heat transfer pipe, and a plurality of fins. The outdoor heat exchanger is configured so that a ratio of a heat capacity of the plurality of fins to a total of heat capacities of the heat transfer pipe and the plurality of fins is not more than 50%. The refrigeration cycle apparatus has a mixed defrosting operation mode in which a hot gas defrosting operation and a reverse-defrosting operation are performed in sequence. In the hot gas defrosting operation, hot gas discharged from the compressor is supplied to the outdoor heat exchanger. In the reverse-defrosting operation, refrigerant passing through the indoor heat exchanger is supplied from the compressor to the outdoor heat exchanger.

A refrigeration cycle apparatus including a refrigerant circuit including a compressor, an indoor heat exchanger, an expansion device, an outdoor heat exchanger, an outside air temperature sensor, and a controller configured to perform a hot gas defrosting operation and a reverse-defrosting operation based on a temperature obtained by the outside air temperature sensor. In the hot gas defrosting operation, hot gas discharged from the compressor without passing through the indoor heat exchanger is supplied to the outdoor heat exchanger. In the reverse-defrosting operation, refrigerant passing through the indoor heat exchanger is supplied from the compressor to the outdoor heat exchanger. The controller has at least a mixed defrosting operation mode in which the hot gas defrosting operation and the reverse-defrosting operation are performed in sequence. The controller is configured to start the mixed defrosting operation mode when the temperature obtained by the outside air temperature sensor satisfies a preset condition.

An air-conditioning apparatus that can prevent freezing of a heat transfer medium even when using a non-azeotropic refrigerant mixture. The air-conditioning apparatus is designed such that when a heat exchanger serves as a cooler that cools a heat transfer medium, it controls a heat medium passage reversing device. This is so that, when a heat transfer medium flowing through a heat medium flow passage will not be frozen, a refrigerant flowing through a refrigerant flow passage and the heat transfer medium flowing through the heat medium flow passage are in counter flow. It is also to control the heat medium passage reversing device so that, when there is a possibility of freezing the heat transfer medium flowing through the heat medium flow passage, the refrigerant flowing through the refrigerant flow passage and the heat transfer medium flowing through the heat medium flow passage are in parallel flow.

When an outdoor air handler performs a heating humidifying operation and an air conditioner performs a cooling operation, a control device adjusts at least one of a to-be-supplied air temperature of the outdoor air handler, a to-be-supplied air flow rate of the outdoor air handler, a to-be-supplied water flow rate of the outdoor air handler, and a cooling temperature that is a temperature at an air heat exchanger of the air conditioner. The control device adjusts the to-be-supplied air temperature and the cooling temperature on the basis of dehumidification information, operation information, temperature information, and humidity information. The operation information is information regarding an operating state of the air conditioner.

When an outdoor air handler performs a heating humidifying operation and an air conditioner performs a cooling operation, a control device adjusts at least one of a to-be-supplied air temperature of the outdoor air handler, a to-be-supplied air flow rate of the outdoor air handler, a to-be-supplied water flow rate of the outdoor air handler, and a cooling temperature that is a temperature at an air heat exchanger of the air conditioner. The control device adjusts the to-be-supplied air temperature and the cooling temperature on the basis of dehumidification information, operation information, temperature information, and humidity information. The operation information is information regarding an operating state of the air conditioner.

A controller equipped with a user interface having a separate schedule review mode, including methods of accessing and/or programming such devices, are disclosed. The controller may include a user interface that can be utilized to initiate a scheduling routine having a separate schedule review mode for displaying one or more schedule parameters of the controller without initiating the editing mode. An illustrative method of accessing a schedule on a controller coupled to a user interface may include the steps of initializing a scheduling routine within the controller, initiating a schedule review mode within the controller, displaying one or more schedule parameters for at least one period on the user interface, and exiting the scheduling routine. One or more of the schedule parameters can be modified, if desired, by initiating a separate editing mode within the controller.