There is presented a heating, ventilation and air conditioning (HVAC) system for conditioning air within a chamber, the system comprising: an inlet, an outlet, and a conditioning unit, the conditioning unit comprising a fan, and a heat exchanger configured to exchange heat with the air within the conditioning unit, wherein during operation, air is urged through conditioning unit by the fan such that heat is exchanged between the air and the heat exchanger, wherein the fan is configured to vary the flow rate of air urged through the conditioning unit to thereby control the amount of heat transferred between the air and the heat exchanger.

A ceiling type air conditioner including an indoor unit having a built-in heat exchanger and a built-in blower, and having a plurality of blowing passages for discharging, to the outside, air having passed through the heat exchanger; a discharge panel having a plurality of inlets into which air discharged through the plurality of blowing passages is delivered, an inner space at least partially communicating with the partiality of inlets, and a ring-or arc-shaped opening for discharging, into a room, air flowing into the inner space; and an air guide module mounted to the discharge panel, and moved upward and downward or rotated so as to vary airflow discharged through the opening.

A ceiling type air conditioner including an indoor unit having a built-in heat exchanger and a built-in blower, and having a plurality of blowing passages for discharging, to the outside, air having passed through the heat exchanger; a discharge panel having a plurality of inlets into which air discharged through the plurality of blowing passages is delivered, an inner space at least partially communicating with the partiality of inlets, and a ring-or arc-shaped opening for discharging, into a room, air flowing into the inner space; and an air guide module mounted to the discharge panel, and moved upward and downward or rotated so as to vary airflow discharged through the opening.

An air-conditioning method suitable for reducing energy consumption is selected. A comparison unit 105 compares first operating efficiency, which is operating efficiency when only first air conditioning is performed, with second operating efficiency, which is operating efficiency when only second air conditioning is performed. The first air conditioning is air conditioning in an air-conditioning target space by an air conditioner, and the second air conditioning is air conditioning in the air-conditioning target space by supplying outdoor air without adjusting a temperature of the outdoor air to the air-conditioning target space. A decision unit 106 decides whether to perform the first air conditioning and whether to perform the second air conditioning, based on a result of comparison between the first operating efficiency and the second operating efficiency by the comparison unit 105.

An HVAC air flow mixing system includes a reclaimed air loop having a duct tee configured to fluidly intersect an HVAC duct downstream of an indoor heat exchanger and a pipe in fluid communication with the duct tee and configured to fluidly communicate with the indoor unit so as to selectively reintroduce a portion of the discharged air back to the indoor unit upstream of the indoor heat exchanger.

An HVAC air flow mixing system includes a reclaimed air loop having a duct tee configured to fluidly intersect an HVAC duct downstream of an indoor heat exchanger and a pipe in fluid communication with the duct tee and configured to fluidly communicate with the indoor unit so as to selectively reintroduce a portion of the discharged air back to the indoor unit upstream of the indoor heat exchanger.

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.

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.

Disclosed is an air conditioner including a structure preventing dew from forming on a surface of a cabinet. The air conditioner includes a housing including an inlet through which air is introduced and an outlet through which air is discharged, a heat exchanger disposed between the inlet and the outlet, a blower disposed inside the housing to suck air through the inlet and to discharge air through the outlet, a discharge panel disposed in front of the housing which includes the outlet, the discharge panel including a plurality of holes through which air discharged from the outlet passes, and an airflow guide disposed between the discharge panel and the blower and configured to guide air discharged from the blower in at least two directions.

Disclosed is an air conditioner including a structure preventing dew from forming on a surface of a cabinet. The air conditioner includes a housing including an inlet through which air is introduced and an outlet through which air is discharged, a heat exchanger disposed between the inlet and the outlet, a blower disposed inside the housing to suck air through the inlet and to discharge air through the outlet, a discharge panel disposed in front of the housing which includes the outlet, the discharge panel including a plurality of holes through which air discharged from the outlet passes, and an airflow guide disposed between the discharge panel and the blower and configured to guide air discharged from the blower in at least two directions.