# US 10,309,675 B2 · Defrosting method for air conditioner and defrosting device for air conditioner > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 10,309,675 B2 - Document ID: US10309675B2 - Status: Granted - Kind: B2 - Application number: 15/500,188 - Filed: 2015-06-26 - Published: 2018-07-26 - Granted: 2019-06-04 - Earliest claimed: 2015-05-22 - Assignees: Gd Midea Heating & Ventilating Equipment Co., Ltd.; Midea Group Co., Ltd. - Applicants: Gd Midea Heating & Ventilating Equipment Co., Ltd.; Midea Group Co., Ltd. - Inventors: Guozhong Yang; Fudang Wei; Yuanyang Li - Web page: https://patentgrep.com/patent/US10309675B2 ## CPC - F24F 11/42: of outdoor units - F24F 11/63: Electronic processing - F24F 11/871: by controlling outdoor fans - F25B 47/02: Defrosting cycles - F24F 2110/12: of the outside air - F24F 2110/22: of the outside air - F24F 2130/10: Weather information or forecasts - 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 The present disclosure provides a defrosting method for an air conditioner. The method includes: acquiring outdoor temperature and outdoor humidity if the air conditioner enters a defrosting mode; judging whether the outdoor temperature and the outdoor humidity satisfy a predetermined condition; and controlling an outdoor fan to rotate reversely according to tube temperature of an outdoor heat exchanger and a defrosting period, so as to defrost a protecting housing surrounding the outdoor heat exchanger if it is judged that the outdoor temperature and the outdoor humidity satisfy the predetermined condition. The defrosting method may efficiently defrost the protecting housing surrounding the outdoor heat exchanger completely. The present disclosure further provides a defrosting device for an air conditioner. ## Claims ### Claim 1 A defrosting method for an air conditioner, wherein the air conditioner comprises a compressor and a four-way valve, and the method comprises: acquiring outdoor temperature and outdoor humidity in response to determining that the air conditioner enters a defrosting mode; judging whether the outdoor temperature is lower than a preset temperature and the outdoor humidity is higher than a preset humidity; and controlling an outdoor fan to rotate reversely according to tube temperature of an outdoor heat exchanger and a period when the air conditioner operates in the defrosting mode, so as to defrost a protecting housing surrounding the outdoor heat exchanger, in response to judging that the outdoor temperature is lower than the preset temperature and the outdoor humidity is higher than the preset humidity; wherein controlling the outdoor fan to rotate reversely according to the tube temperature of the outdoor heat exchanger and the period when the air conditioner operates in the defrosting mode comprises: controlling the outdoor fan to rotate reversely in response to determining that the tube temperature is higher than a difference between preset temperature for exiting from the defrosting mode and a first temperature threshold; or controlling the outdoor fan to rotate reversely in response to determining that the period when the air conditioner operates in the defrosting mode reaches a difference between a preset defrosting period and a first period threshold. ### Claim 2 (depends on 1) The defrosting method according to claim 1, before acquiring the outdoor temperature and the outdoor humidity, further comprising acquiring information of current weather, wherein if the current weather is at least one of raining and snowing, judging whether the outdoor temperature is lower than first preset temperature and the outdoor humidity is higher than first preset humidity; and if the current weather is neither the raining nor the snowing, judging whether the outdoor temperature is lower than second preset temperature and the outdoor humidity is higher than second preset humidity, wherein the second preset temperature is higher than the first preset temperature and the second preset humidity is lower than the first preset humidity. ### Claim 3 (depends on 1) The defrosting method according to claim 1, if the outdoor temperature is greater than or equal to the preset temperature and the outdoor humidity is lower than or equal to the preset humidity, the air conditioner is controlled by the controlling module to exit from the defrosting mode when the tube temperature of the outdoor heat exchanger is higher than preset temperature for exiting from the defrosting mode or the period when the air conditioner operates in the defrosting mode reaches preset defrosting period. ### Claim 4 A defrosting device for an air conditioner, wherein the air conditioner comprises a compressor and a four-way valve, and the device comprises: an acquiring module, configured to acquire outdoor temperature and outdoor humidity if the air conditioner enters a defrosting mode; a controlling module, configured to judge whether the outdoor temperature is lower than a preset temperature and the outdoor humidity is higher than a preset humidity; and control an outdoor fan to rotate reversely according to tube temperature of an outdoor heat exchanger and a period when the air conditioner operates in the defrosting mode, so as to defrost a protecting housing surrounding the outdoor heat exchanger, in response to judging that the outdoor temperature is lower than the preset temperature and the outdoor humidity is higher than the preset humidity; wherein the controlling module is further configured to: control the outdoor fan to rotate reversely in response to determining that the tube temperature is higher than a difference between preset temperature for exiting from the defrosting mode and a first temperature threshold; or control the outdoor fan to rotate reversely in response to determining that the period when the air conditioner operates in the defrosting mode reaches a difference between a preset defrosting period and a first period threshold. ### Claim 5 (depends on 4) The defrosting device according to claim 4, wherein before acquiring the outdoor temperature and the outdoor humidity, the acquiring module is further configured to acquire information of current weather, wherein if the current weather is at least one of raining and snowing, the controlling module judges whether the outdoor temperature is lower than first preset temperature and the outdoor humidity is higher than first preset humidity; and if the current weather is neither the raining nor the snowing, the controlling module judges whether the outdoor temperature is lower than second preset temperature and the outdoor humidity is higher than second preset humidity, wherein the second preset temperature is higher than the first preset temperature and the second preset humidity is lower than the first preset humidity. ### Claim 6 (depends on 4) The defrosting device for an air conditioner according to claim 4, if the controlling module judges that the outdoor temperature is greater than or equal to the preset temperature and the outdoor humidity is lower than or equal to the preset humidity, the air conditioner is controlled by the controlling module to exit from the defrosting mode when the tube temperature of the outdoor heat exchanger is higher than preset temperature for exiting from the defrosting mode or the period when the air conditioner operates in the defrosting mode reaches preset defrosting period. ### Claim 7 An air conditioner, comprising: a compressor; a four-way valve; and a defrosting device for defrosting the air conditioner, said defrosting device comprising: an acquiring module, configured to acquire outdoor temperature and outdoor humidity if the air conditioner enters a defrosting mode; a controlling module, configured to judge whether the outdoor temperature is lower than a preset temperature and the outdoor humidity is higher than a preset humidity; and control an outdoor fan to rotate reversely according to tube temperature of an outdoor heat exchanger and a period when the air conditioner operates in the defrosting mode, so as to defrost a protecting housing surrounding the outdoor heat exchanger, in response to judging that the outdoor temperature is lower than the preset temperature and the outdoor humidity is higher than the preset humidity; wherein the controlling module is further configured to: control the outdoor fan to rotate reversely in response to determining that the tube temperature is higher than a difference between preset temperature for exiting from the defrosting mode and a first temperature threshold; or control the outdoor fan to rotate reversely in response to determining that the period when the air conditioner operates in the defrosting mode reaches a difference between a preset defrosting period and a first period threshold. ### Claim 8 (depends on 7) The air conditioner according to claim 7, wherein before acquiring the outdoor temperature and the outdoor humidity, the acquiring module is further configured to acquire information of current weather, wherein if the current weather is at least one of raining and snowing, the controlling module judges whether the outdoor temperature is lower than first preset temperature and the outdoor humidity is higher than first preset humidity; and if the current weather is neither the raining nor the snowing, the controlling module judges whether the outdoor temperature is lower than second preset temperature and the outdoor humidity is higher than second preset humidity, wherein the second preset temperature is higher than the first preset temperature and the second preset humidity is lower than the first preset humidity. ### Claim 9 (depends on 7) The air conditioner according to claim 7, if the controlling module judges that the outdoor temperature is greater than or equal to the preset temperature and the outdoor humidity is lower than or equal to the preset humidity, the air conditioner is controlled by the controlling module to exit from the defrosting mode when the tube temperature of the outdoor heat exchanger is higher than preset temperature for exiting from the defrosting mode or the period when the air conditioner operates in the defrosting mode reaches preset defrosting period.