# US 2022/0034534 A1 · Air-conditioning apparatus > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 2022/0034534 A1 - Document ID: US20220034534A1 - Status: Published application - Kind: A1 - Application number: 17/278,915 - Filed: 2018-11-20 - Published: 2022-02-03 - Earliest claimed: 2018-11-20 - Assignees: Mitsubishi Electric Corporation - Applicants: Mitsubishi Electric Corporation - Inventors: Kazuki WATANABE; Masahiko TAKAGI - Web page: https://patentgrep.com/patent/US20220034534A1 ## CPC - F24F 11/36: to leakage of heat-exchange fluid - F24F 11/52: Indication arrangements, e.g. displays - F24F 11/526: giving audible indications - F24F 11/56: Remote control - F25B 49/005: {of safety devices (F25B49/02 and F25B49/04 take precedence)} - F24F 2120/10: Occupancy - F24F 2130/00: Control inputs relating to environmental factors not covered by group F24F2110/00 - F25B 2400/12: Inflammable refrigerants - F25B 2500/222: Detecting refrigerant leaks - F24F: AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING (removing dirt or fumes from areas where they are produced B08B15/00; vertical ducts for carrying away waste gases from buildings E04F17/02; tops for chimneys or ventilating shafts, terminals for flues F23L17/02) - F25B: REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS ## Abstract In an air-conditioning apparatus, an indoor unit and an outdoor unit are connected to each other by a refrigerant pipe through which refrigerant flows. The air-conditioning apparatus includes: a refrigerant detection unit that detects a leak of the refrigerant in the indoor unit; a notification unit that makes a notification indicating occurrence of the leak of the refrigerant; a controller that controls at least the notification unit; and a remote control unit configured to operate the indoor unit. When the refrigerant detection unit detects the leak of the refrigerant, the controller controls the notification unit to make in a first mode the notification indicating the occurrence of the leak of the refrigerant, and make the notification in a second mode different from the first mode after a predetermined time period elapses from time at which the notification in the first mode is made. Thus, since the notification of the refrigerant leak is made two steps, that is, in the first mode in a first step and in the second mode in a second step, it is possible to cause a user to pay more attention to the notifications, and thus cause the user to easily notice the notification. It is therefore possible to cause the user to sufficiently know the refrigerant leak. ## Claims ### Claim 1 An air-conditioning apparatus provided with an indoor unit and an outdoor unit that are connected to each other by a refrigerant pipe through which refrigerant flows, the air-conditioning apparatus comprising: a refrigerant detection unit configured to detect a leak of the refrigerant in the indoor unit; a notification unit configured to make a notification indicating occurrence of the leak of the refrigerant; a controller configured to control at least the notification unit; and a remote control unit configured to operate the indoor unit, wherein when the refrigerant detection unit detects the leak of the refrigerant, the controller controls the notification unit to make in a first mode the notification indicating the occurrence of the leak of the refrigerant, makes a determination whether the notification in the first mode is recognized or not, and controls the notification unit to make the notification in a second mode different from the first mode, based on a result of the determination. ### Claim 2 (depends on 1) The air-conditioning apparatus of claim 1, wherein when an operation by the remote control unit is not performed even after the predetermined time period elapses from the time at which the notification in the first mode is made, the controller controls the notification unit to make in the second mode the notification indicating the occurrence of the leak of the refrigerant. ### Claim 3 (depends on 1) The air-conditioning apparatus of claim 1, further comprising: a human sensor configured to detect presence of a person in the vicinity of the indoor unit, wherein the controller controls the notification unit to make in the second mode the notification indicating the occurrence of the leak of the refrigerant, when the human sensor detects the presence of the person in the vicinity of the indoor unit after the predetermined time period elapses from the time at which the notification in the first mode is made. ### Claim 4 (depends on 1) The air-conditioning apparatus of claim 1, further comprising: an opening/closing detection unit configured to detect opening/closing of a window or a door of a room in which the indoor unit is installed, wherein the controller controls the notification unit to make in the second mode the notification indicating the occurrence of the leak of the refrigerant, when the opening/closing detection unit does not detect the opening/closing of the window or the door even after the predetermined time period elapses from the time at which the notification in the first mode is made. ### Claim 5 (depends on 1) The air-conditioning apparatus of claim 1, wherein: the notification unit includes at least one of the remote control unit and a display unit or a speaker that is provided at a surface of a housing of the indoor unit; the notification in the first mode includes at least one of a notification that is made by outputting buzzer sound or voice from the speaker or the remote control unit, and a notification that is made by lighting a lamp, causing the lamp to blink, or displaying a message on the display unit or the remote control unit; and the notification in the second mode includes at least one of a notification that is made by outputting buzzer sound or voice in a larger volume, a notification that is made by lighting the lamp, causing the lamp to blink, or displaying the message at a higher brightness, and a notification that is made by causing the lamp to blink with a higher frequency, than the notification in the first mode. ### Claim 6 (depends on 1) The air-conditioning apparatus of claim 1, further comprising: a shutoff valve provided at the refrigerant pipe, and configured to shut off a flow of the refrigerant between the indoor unit and the outdoor unit, wherein when the refrigerant detection unit detects the leak of the refrigerant, the controller switches a state of the shutoff valve from an open state to a closed state. ### Claim 7 (depends on 1) The air-conditioning apparatus of claim 1, wherein when the refrigerant detection unit detects the leak of the refrigerant, the controller forcibly operates an air-sending device provided in the indoor unit. ### Claim 8 (depends on 1) The air-conditioning apparatus of claim 1, wherein when a plurality of indoor units including the indoor unit are provided, the controller controls the notification unit to make the notification in the first mode and in different manners for one of the plurality of indoor units in which the leak of the refrigeration is detected by the refrigerant detection unit and a remaining one or ones of the plurality of indoor units. ### Claim 9 (depends on 1) The air-conditioning apparatus of claim 1, further comprising: a management device configured to manage an operation state of the air-conditioning apparatus; and a communication unit connected to the management device, wherein when the refrigerant detection unit detects the leak of the refrigerant, the controller controls the communication unit to notify the management device of occurrence of the leak of the refrigerant.