An air-conditioning apparatus according to the present disclosure includes a heat medium circulation circuit, a heat-source-side device, and a voltage drop device. In the heat medium circulation circuit, a pump, an indoor heat exchanger, and a flow control device are connected by pipes to circulate the heat medium. The pump sends a heat medium that contains water or brine and transfers heat. The indoor heat exchanger causes heat exchange to be performed between the heat medium and an indoor air in an air-conditioned space. The flow control device controls a flow rate of the heat medium in the indoor heat exchanger. The heat-source-side device heats or cools the heat medium before the heat medium is sent to the indoor heat exchanger. The voltage drop device reduces a voltage that is applied to the pump based on a value of a current that is supplied to the pump, in association with a flow rate of the heat medium in the heat medium circulation circuit.

An air-conditioning apparatus according to the present disclosure includes a heat medium circulation circuit, a heat-source-side device, and a voltage drop device. In the heat medium circulation circuit, a pump, an indoor heat exchanger, and a flow control device are connected by pipes to circulate the heat medium. The pump sends a heat medium that contains water or brine and transfers heat. The indoor heat exchanger causes heat exchange to be performed between the heat medium and an indoor air in an air-conditioned space. The flow control device controls a flow rate of the heat medium in the indoor heat exchanger. The heat-source-side device heats or cools the heat medium before the heat medium is sent to the indoor heat exchanger. The voltage drop device reduces a voltage that is applied to the pump based on a value of a current that is supplied to the pump, in association with a flow rate of the heat medium in the heat medium circulation circuit.

An air-conditioner having a fluid tank configured to connect an indoor unit of the air-conditioner with an outdoor unit of the air-conditioner. The fluid tank comprises a first chamber, and a second chamber. The first chamber comprises a high-pressure inlet and a high-pressure outlet. The second chamber comprises a low-pressure inlet, a low-pressure outlet and a low-pressure filling opening.

An air-conditioner having a fluid tank configured to connect an indoor unit of the air-conditioner with an outdoor unit of the air-conditioner. The fluid tank comprises a first chamber, and a second chamber. The first chamber comprises a high-pressure inlet and a high-pressure outlet. The second chamber comprises a low-pressure inlet, a low-pressure outlet and a low-pressure filling opening.

A system and method of retrofitting a heating, ventilation, air conditioning, and refrigeration system (HVACR) including one or more brazed, soldered, or mechanical connections between refrigerant lines is disclosed. The method includes removing a refrigerant from the HVACR system. The refrigerant that is removed is a non-flammable refrigerant. An enclosure is installed over the one or more brazed, soldered, or mechanical connections between refrigerant lines. A refrigerant is added to the HVACR system. The refrigerant being added has a global warming potential (GWP) that is relatively lower than the refrigerant removed from the HVACR system. The refrigerant being added has a relatively higher flammability than the refrigerant removed from the HVACR system.

A system and method of retrofitting a heating, ventilation, air conditioning, and refrigeration system (HVACR) including one or more brazed, soldered, or mechanical connections between refrigerant lines is disclosed. The method includes removing a refrigerant from the HVACR system. The refrigerant that is removed is a non-flammable refrigerant. An enclosure is installed over the one or more brazed, soldered, or mechanical connections between refrigerant lines. A refrigerant is added to the HVACR system. The refrigerant being added has a global warming potential (GWP) that is relatively lower than the refrigerant removed from the HVACR system. The refrigerant being added has a relatively higher flammability than the refrigerant removed from the HVACR system.

A climate control system coupled within an opening of a structure, with the opening separating an internal area within the structure and an exterior area external to the structure, the climate control system straddling the opening. The climate control system includes: an interior unit disposed at the opening within the internal area; an exterior unit disposed at the opening in the exterior area; and a connector between the interior unit and the exterior unit that extends through the opening, the connector including: a circulation hose that extends through the opening to connect the exterior unit and the interior unit, and a controls system configured to operate the interior unit and the exterior unit.

A climate control system coupled within an opening of a structure, with the opening separating an internal area within the structure and an exterior area external to the structure, the climate control system straddling the opening. The climate control system includes: an interior unit disposed at the opening within the internal area; an exterior unit disposed at the opening in the exterior area; and a connector between the interior unit and the exterior unit that extends through the opening, the connector including: a circulation hose that extends through the opening to connect the exterior unit and the interior unit, and a controls system configured to operate the interior unit and the exterior unit.

An air conditioning system and a control method thereof. The air conditioning system includes: a plurality of indoor units connected in parallel; a plurality of outdoor units connected in parallel; and a coolant circulation circuit which circulates coolant through each of the indoor units connected in parallel and each of the outdoor units connected in parallel respectively, and which exchanges heat with each of the indoor units and each of the outdoor units; wherein the air conditioning system further includes a controller which, based on a number of actively operating indoor units, a total number of the indoor units and a total number of the outdoor units, defines an upper limit of a number of actively operating outdoor units, so that the flow rate of the coolant flowing through the actively operating outdoor units is not lower than a preset flow rate.

An air conditioning system and a control method thereof. The air conditioning system includes: a plurality of indoor units connected in parallel; a plurality of outdoor units connected in parallel; and a coolant circulation circuit which circulates coolant through each of the indoor units connected in parallel and each of the outdoor units connected in parallel respectively, and which exchanges heat with each of the indoor units and each of the outdoor units; wherein the air conditioning system further includes a controller which, based on a number of actively operating indoor units, a total number of the indoor units and a total number of the outdoor units, defines an upper limit of a number of actively operating outdoor units, so that the flow rate of the coolant flowing through the actively operating outdoor units is not lower than a preset flow rate.