A system comprising a compressor, a first valve coupled to the compressor and to a first coil, a first expansion valve coupled to the first coil, and a second expansion valve. The second expansion valve coupled to a second coil. A second valve is coupled to the second coil and the compressor. A third valve is coupled to the compressor and a third coil. In response to receiving a heating demand that is below a threshold heating demand, a controller induces an artificial heating demand.

A system comprising a compressor, a first valve coupled to the compressor and coupled to a first coil, a first expansion valve coupled to the first coil, a second coil, and a second expansion valve. The second expansion valve coupled to a third coil, a second valve coupled to the compressor and the third coil. A controller operable to operate the first valve, the first expansion valve, the second expansion valve, and the second valve. The second coil is coupled to the compressor and the refrigerant flows from the second coil to the compressor.

An air conditioner includes an outdoor unit having a compressor and an outdoor heat exchanger. A ventilator connected to the outdoor unit by refrigerant pipes allows outside air to pass through a heat exchanger and flow into an indoor space, and allows indoor air to pass through the heat exchanger and flow to an outdoor space. The ventilator includes a supply passage through which the outside air flows into the indoor space, and a discharge passage through which the indoor air is discharged to the outdoor space. The ventilaro also includes a main heat exchanger in the supply passage and a recovery heat exchanger in the discharge passage. A refrigerant distributor supplies the refrigerant from the outdoor unit to the main heat exchanger or the recovery heat exchanger, vice-versa. A reheat exchanger in the supply passage heats the air flowing therethrough.

An air conditioning system includes: an outdoor unit; indoor units; one or more refrigerant flow path switching devices that switch flow paths of a refrigerant between the outdoor unit and the indoor units; and external pipes extending from the outdoor unit to the indoor units. The air conditioning system is configured such that a sum of a first value and a first correction value is equal to or less than a predetermined upper limit value determined based on an industrial standard, where the first value is based on a total length of the external pipes from the outdoor unit to the indoor units via the one or more refrigerant flow path switching device, and the first correction value is based on a sum of capabilities of the indoor units connected to the one or more refrigerant flow path switching devices.

The present disclosure relates to a heat pump system comprising an outdoor unit disposed in an outdoor space, a plurality of thermal load units supplied with cool air and hot air, and an intermediate unit disposed between the outdoor unit and the plurality of thermal load units, wherein the intermediate unit is connected to the outdoor unit through refrigerant pipes and connected to the plurality of thermal load units through thermal medium pipes.

A multi-type air conditioner may include three pipes, including a high-pressure pipe, a low-pressure pipe, and a liquid line which may be connected to a plurality of indoor units, in which some of the indoor units may be operated in a cooling mode and the rest of the indoor units may be operated in a heating mode, such that waste heat from the indoor units operated in the heating mode may be recovered to be used for the indoor units operated in the cooling mode.

An air conditioner includes an outdoor unit in which a refrigerant circulates; an indoor unit in which water circulates; a heat exchange device including a heat exchanger that connects the outdoor unit to the indoor unit and performs heat exchange between the refrigerant and the water; a first outdoor unit connection pipe configured to connect the outdoor unit and the heat exchange device, a high-pressure gaseous refrigerant flowing in the first outdoor unit connection pipe; a second outdoor unit connection pipe configured to connect the outdoor unit and the heat exchange device, a low-pressure gaseous refrigerant flowing in the second outdoor unit connection pipe; a third outdoor unit connection pipe configured to connect the outdoor unit and the heat exchange device, a liquid refrigerant lowing in the third outdoor unit connection pipe; a bypass pipe configured to communicate the third outdoor unit connection pipe and the second outdoor unit connection pipe; and a bypass valve provided in the bypass pipe.

An air conditioning system includes a storage medium and an air conditioning system, for a three-pipe air conditioning system, the three-pipe air conditioning system includes a compressor, an outdoor heat exchanger, an indoor heat exchanger, a gas-liquid separator, a first pipeline, a second pipeline and a third pipeline; the oil return control method comprises the following steps: controlling the compressor to operate at a first frequency in a refrigerating mode; judging whether the operation duration of the refrigerating mode reaches a first preset time or not; if so, the air conditioning system enters an oil return state, and the compressor, the third pipeline, the second pipeline and the gas-liquid separator are controlled to be communicated in sequence to form a refrigerant circulation loop.

In an air-conditioning apparatus including a plurality of indoor units connected to a heat medium converter and a plurality of remote controllers respectively provided for the indoor units, the remote controllers each include a temperature sensor that detect a temperature of a corresponding space to be air-conditioned, and are each configured to communicate with a heat medium converter controller of the heat medium converter and an indoor unit controller of the corresponding indoor unit, transmit an instruction to start and stop an operation and data related to rotation speed of an indoor air-sending device to the corresponding indoor unit controller, and transmit the instruction to start and stop the operation, and a target temperature and a temperature detected by the temperature sensor or a difference therebetween, to the heat medium converter controller.

An air conditioning system may include an outdoor unit including a compressor; at least one distributor connected to the outdoor unit and including a condenser and an evaporator that exchange heat between refrigerant and water; a plurality of heating pipes in communication with the condenser; a plurality of cooling pipes in communication with the evaporator; a plurality of fan coil units connected to the plurality of heating pipes or the plurality of cooling pipes; and a controller configured to perform a heating pipe search operation for matching a portion of the plurality of fan coil units with the plurality of heating pipes, and a cooling pipe search operation for matching another portion of the plurality of fan coil units with the plurality of cooling pipes, in parallel.