REFRIGERATING AND AIR-CONDITIONING APPARATUS

摘要

A refrigerating and air-conditioning apparatus performs, even during a heating operation under air conditions leading to formation of frost, a defrosting operation while simultaneously continuing the heating operation and improves comfort through heating by securing an appropriate amount of ventilation. A plurality of refrigeration cycles independently performs a heating operation and a defrosting operation. By controlling a ventilation damper of an indoor unit that is to perform a defrosting operation to increase the amount of ventilation, a prior ventilation operation for securing the time-averaged required amount of ventilation including the period in which the defrosting operation is being performed is performed before the defrosting operation, and after the prior ventilation is terminated, the defrosting operation is started.

主权项

1. A refrigerating and air-conditioning apparatus comprising:
a plurality of refrigeration cycles that each include a compressor, a four-way valve, an outdoor heat exchanger, a pressure reducing device, and an indoor heat exchanger that are connected to one another, the plurality of refrigeration cycles being capable of independently performing a heating operation and a defrosting operation; a plurality of indoor units each provided with the indoor heat exchanger that is included in each of the plurality of refrigeration cycles, the plurality of indoor units that each include an indoor fan for taking in outside air through the ventilation port and sending the air into a room, and a ventilation damper for opening and closing the ventilation port; and a controller that controls the ventilation damper to perform indoor ventilation during the heating operation, and that controls the ventilation damper of each of the plurality of indoor units to close the corresponding ventilation port and stop indoor ventilation during a defrosting operation, wherein the plurality of indoor units are installed in the same room, and wherein prior to a defrosting operation, the controller performs a prior ventilation operation to increase the amount of ventilation by controlling the ventilation damper of the indoor unit of a refrigeration cycle that is to perform the defrosting operation, and after termination of the prior ventilation operation, the controller starts the defrosting operation.