Provided are a control method and apparatus for increasing the amount of a circulating refrigerant, and an air conditioner. The control method includes: when a refrigerating capacity need is equivalent to a heating capacity need in the operation of an air-conditioning system, determining whether the discharge temperature of a compressor is greater than a preset safety alert value; if the discharge temperature of the compressor is greater than the safety alert value, adjusting the frequency of a fan of an outdoor heat exchanger; and when the discharge temperature of the compressor is not greater than the safety alert value, controlling to stop the adjustment of the frequency of the fan, and maintaining the air-conditioning system to operate at the adjusted current frequency of the fan.

A water distribution apparatus and method including cold and hot water supplies, a fan coil (or chilled beam device), a control valve having cold and hot water inlets and outlets, cold and hot water outputs configured to supply cold and hot water to the fan coil, cold and hot water return inlets configured to receive from the fan coil the water supplied by the cold and/or water outputs and outputting the cold and/or hot water to the cold and hot water supply lines, respectively, via the cold and hot water outlets, respectively. Cold and hot water is supplied from the cold and/or hot water outputs to the fan coil and received into the cold and hot water return inlets, respectively, and the cold and hot water supplied by the cold and hot water outputs to the fan coil is output to the cold and hot water supply lines, respectively.

A water distribution apparatus and method including cold and hot water supplies, a fan coil (or chilled beam device), a control valve having cold and hot water inlets and outlets, cold and hot water outputs configured to supply cold and hot water to the fan coil, cold and hot water return inlets configured to receive from the fan coil the water supplied by the cold and/or water outputs and outputting the cold and/or hot water to the cold and hot water supply lines, respectively, via the cold and hot water outlets, respectively. Cold and hot water is supplied from the cold and/or hot water outputs to the fan coil and received into the cold and hot water return inlets, respectively, and the cold and hot water supplied by the cold and hot water outputs to the fan coil is output to the cold and hot water supply lines, respectively.

A free cooling unit including a heat exchanger to allow heat exchange between a first fluid and a second fluid; a first pumping assembly to pump the first fluid through a first hydraulic circuit from a first inlet port of the unit to a first outlet port of the unit; a second pumping assembly to pump the second fluid through a second hydraulic circuit from a second inlet port of the unit to a second outlet port of the module and a control module to control the functioning of the unit. The unit further includes a diverter assembly arranged between the first pumping assembly and the heat exchanger and configured to switch between a first state in which the first fluid is directed through the heat exchanger before reaching the first outlet port and a second state in which the first fluid is directly directed to the first outlet port.

A free cooling unit including a heat exchanger to allow heat exchange between a first fluid and a second fluid; a first pumping assembly to pump the first fluid through a first hydraulic circuit from a first inlet port of the unit to a first outlet port of the unit; a second pumping assembly to pump the second fluid through a second hydraulic circuit from a second inlet port of the unit to a second outlet port of the module and a control module to control the functioning of the unit. The unit further includes a diverter assembly arranged between the first pumping assembly and the heat exchanger and configured to switch between a first state in which the first fluid is directed through the heat exchanger before reaching the first outlet port and a second state in which the first fluid is directly directed to the first outlet port.

A safety system for a heat pump system includes a plurality of valve units each having refrigerant pipe portions with control valves, a refrigerant leakage detector, and a casing accommodating the valves and the refrigerant leakage detector and formed with first and second openings. The safety system further includes a connection structure connecting the internal spaces of the casings via the first and second openings, and a discharge structure connected to the connection structure or one of the casings and configured to discharge air from the internal space of the casing in which a refrigerant leakage has occurred. The casing has first and second lateral faces facing different directions, and the first opening is formed in the first lateral face and the second opening is formed in the second lateral face.

A safety system for a heat pump system includes a plurality of valve units each having refrigerant pipe portions with control valves, a refrigerant leakage detector, and a casing accommodating the valves and the refrigerant leakage detector and formed with first and second openings. The safety system further includes a connection structure connecting the internal spaces of the casings via the first and second openings, and a discharge structure connected to the connection structure or one of the casings and configured to discharge air from the internal space of the casing in which a refrigerant leakage has occurred. The casing has first and second lateral faces facing different directions, and the first opening is formed in the first lateral face and the second opening is formed in the second lateral face.

A single-stage carbon dioxide multi-split cooling and heating multifunctional central air conditioner, comprising a single-stage carbon dioxide circulation system using carbon dioxide as a circulation working medium; the single-stage carbon dioxide circulation system comprises an outdoor unit and a plurality of end heat exchangers provided in parallel; and the carbon dioxide medium performs cooling and/or heating in a circulating manner in a carbon dioxide compressor, an outdoor heat exchanger, a liquid storage tank and the end heat exchangers which are in communication with one another.

According to one embodiment, in a low speed drive of outdoor fans, a first flow rate adjusting valve in a main outdoor heat exchanger side is narrowed to a closing degree or a close range thereof, and an opening degree of a second flow rate adjusting valve is controlled such that a supercooling degree of refrigerant in auxiliary outdoor heat exchangers becomes constantly a target value.

According to one embodiment, in a low speed drive of outdoor fans, a first flow rate adjusting valve in a main outdoor heat exchanger side is narrowed to a closing degree or a close range thereof, and an opening degree of a second flow rate adjusting valve is controlled such that a supercooling degree of refrigerant in auxiliary outdoor heat exchangers becomes constantly a target value.