An indoor unit of an air-conditioning apparatus includes an air outlet; and a blowout flow passage connected to the air outlet and guides air subjected to heat exchange at a heat exchanger to the air outlet. In a cross section perpendicular to an air flow direction in the blowout flow passage, the passage has a first end and a second end in a longitudinal direction. The blowout flow passage is divided into first regions, a second region, and third regions. The first regions include the first end and the second end. The second region includes a center position in the longitudinal direction of the passage. The third regions are between the first regions and the second region in the longitudinal direction.

A heating, ventilation, and/or air conditioning (HVAC) unit includes a terminal unit. The terminal unit includes a housing having a first panel bordering a return airflow path, a second panel bordering an additional airflow path, and a separating wall disposed between and bordering the return airflow path and the additional airflow path. The terminal unit also includes a sound attenuator formed by the first panel and the separating wall.

An air diffuser of a heating, ventilation, and/or air conditioning (HVAC) system includes a mixing chamber having a circulation inlet and a mixing region, a room air intake fluidly coupled with the circulation inlet and separated from the mixing region by a blank-off plate, and a nozzle. The nozzle is disposed adjacent to the circulation inlet and configured to accelerate a conditioned air flow into the mixing region such that unconditioned room air is induced by the conditioned air flow to enter the mixing region through the circulation inlet and from the room air intake.

An air conditioning diffuser assembly includes an air intake member mounted on an elongate upper member formed with an opening to let air pass through from the air intake member. A corner panel extends at a non-zero angle from the elongate upper member. A first corner mounting panel extends from the corner panel. A second corner mounting panel extends from the elongate upper member. Ends of the first and second corner mounting panels are separated by an elongate gap. A diffuser is mounted inside the air conditioning diffuser assembly. A bottom edge of the diffuser is mounted at a juncture between the corner panel and the first corner mounting panel and a top edge of the diffuser is mounted at a juncture between the elongate upper member and the second corner mounting panel.

An air conditioning system includes: an intake unit configured to take in return air of an indoor space from a ceiling of the indoor space; an outdoor air processing unit configured to supply outdoor air while exhausting the return air taken in via the intake unit to outdoors; an air conditioner configured to supply, as air-conditioning air, mixed air of the return air taken in via the intake unit and the outdoor air supplied by the outdoor air processing unit; and at least one radiation unit disposed in the indoor space in a manner to surround the intake unit, the radiation unit being configured to radiate heat of the air-conditioning air supplied by the air conditioner while discharging the air-conditioning air to the indoor space.

A diffuser assembly includes a housing that defines an internal chamber having an open end, a return air outlet, and a supply air inlet; a cover sized to cover the open end, wherein the cover defines a return air inlet and a supply air outlet; and an internal return air duct longitudinally extending within the internal chamber and connecting the return air inlet and the return air outlet, wherein the internal return air duct includes an inner duct surface that defines a return air chamber within the internal return air duct and an outer duct surface that defines a supply air chamber between the housing and the outer duct surface, wherein the supply air chamber defines a supply air path between the supply air inlet and the supply air outlet.

An air-conditioning apparatus includes: a housing having a first space and a second space that are adjacent to each other; a fan provided in the first space and to suck air into the housing; a heat exchanger provided in the first space and cause heat exchange with the air sucked by the fan to be performed; a refrigerant sensor provided in the second space and to detect refrigerant; and a partition plate provided to partition off the first space and the second space and having an air inlet port and an air outlet port.

A ceiling-embedded air conditioner includes: a ceiling-embedded casing body; a turbo fan disposed inside the casing body; a heat exchanger disposed inside the casing body on an outer peripheral side of the turbo fan; and an electrical equipment box disposed along a part of the heat exchanger at the upstream side of a ventilation direction. The casing body has a square shape with first to fourth side plates. The heat exchanger has first to fourth heat exchange portions bent along the first to fourth side plates respectively. An end portion of the first heat exchange portion and an end portion of the fourth heat exchange portion are disposed at a corner for tube connection out of the four corners of the casing body. The electrical equipment box is disposed to extend from the corner for tube connection toward the first heat exchange portion and the fourth heat exchange portion.

Disclosed herein is an air conditioner capable of guiding air in a desired direction with an adjusted speed without marring the appearance to solve the above-described problems. An air conditioner comprising a ceiling-embedded type indoor unit configured to discharge air into an indoor room through an air outlet simultaneously sucking indoor air through an air inlet, wherein a air conditioner comprises, a main flap configured to guide a direction of air discharged from a air outlet in a preset direction, and a sub-flap configured to guide the direction of air between the main flap and the sub-flap in the preset direction, wherein a length of a main flap in a direction where air flows is longer than that of the sub-flap in the direction where air flows.

An air conditioning system includes: an intake unit configured to take in return air of an indoor space from a ceiling of the indoor space; an outdoor air processing unit configured to supply outdoor air while exhausting the return air taken in via the intake unit to outdoors; an air conditioner configured to supply, as air-conditioning air, mixed air of the return air taken in via the intake unit and the outdoor air supplied by the outdoor air processing unit; and at least one radiation unit disposed in the indoor space in a manner to surround the intake unit, the radiation unit being configured to radiate heat of the air-conditioning air supplied by the air conditioner while discharging the air-conditioning air to the indoor space.