# US 11,079,300 B2 · Air cooling heat pump system, refrigerant leakage detection method and detection system air cooling heat pump system thereof > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,079,300 B2 - Document ID: US11079300B2 - Status: Granted - Kind: B2 - Application number: 16/380,625 - Filed: 2019-04-10 - Published: 2019-10-24 - Granted: 2021-08-03 - Earliest claimed: 2018-04-13 - Assignees: Carrier Corporation - Applicants: Carrier Corporation - Inventors: Runfu Shi; Hui Zhai; Xiangyu Gao; Guangyu Shen; Yu Zhu; YuHui Kuang - Web page: https://patentgrep.com/patent/US11079300B2 ## CPC - F25B 13/00: Compression machines, plants or systems, with reversible cycle (defrosting cycles F25B47/02) - G01M 3/2815: {using pressure measurements} - F25B 49/005: {of safety devices (F25B49/02 and F25B49/04 take precedence)} - F25B 2500/222: Detecting refrigerant leaks - F25B 2700/04: Refrigerant level - F25B: REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS - G01M: TESTING STATIC OR DYNAMIC BALANCE OF MACHINES OR STRUCTURES; TESTING OF STRUCTURES OR APPARATUS, NOT OTHERWISE PROVIDED FOR ## Abstract A refrigerant leak detecting method for an air-cooling heat pump system in a heating mode comprises S110, S210, obtaining a leak indication parameter set, wherein the leak indication parameter set at least includes a refrigerant level in a liquid reservoir and/or a supercooling degree; S120, S220, comparing each leak indication parameter in the leak indication parameter set with a corresponding preset indication parameter interval; S130, S230, when each leak indication parameter falls within a corresponding preset indication parameter interval, obtaining and recording a corresponding evaluated refrigerant leak amount; S140, S240, when a cumulative value of the evaluated refrigerant leak amount falls within a preset refrigerant leak interval, determining that a refrigerant leak occurs in the air-cooling heat pump system; when the cumulative value of the evaluated refrigerant leak amount does not fall within the preset refrigerant leak interval, returning to the step S110, S210. ## Claims ### Claim 1 A refrigerant leak detecting method for an air-cooling heat pump system, wherein the method comprises: (i), obtaining a leak indication parameter set, wherein the leak indication parameter set at least includes, in a heating mode of the air-cooling heat pump system, a refrigerant level in a liquid reservoir and in a cooling mode of the air-cooling heat pump system, a subcooling degree; (ii), comparing each leak indication parameter in the leak indication parameter set with a corresponding preset indication parameter interval; (iii), when each leak indication parameter falls within the corresponding preset indication parameter interval, obtaining and recording a corresponding evaluated refrigerant leak amount; (iv), when a cumulative value of the evaluated refrigerant leak amount falls within a preset refrigerant leak interval, determining that a refrigerant leak occurs in the air-cooling heat pump system; when the cumulative value of the evaluated refrigerant leak amount does not fall within the preset refrigerant leak interval, returning to the step (i); wherein the leak indication parameter set further includes one or more of the following: compressor speed or compressor capacity, and expansion valve opening and superheat degrees, and compressor discharge pressure; wherein leak indication parameters in the leak indication parameter set are each used to indicate different refrigerant leak degrees; in the step (ii), the leak indication parameters in the leak indication parameter set are each compared with the corresponding preset indication parameter intervals according to a trend indicating refrigerant leak degrees from high to low; wherein the compressor speed or the compressor capacity; the expansion valve opening and superheat degrees; and the refrigerant level are used to indicate refrigerant leak degrees from high to low, respectively; or alternatively the compressor speed or compressor capacity; the expansion valve opening and superheat degrees; the compressor discharge pressure; and the subcooling degree are used to indicate the refrigerant leak degrees from high to low, respectively. ### Claim 2 (depends on 1) The detecting method according to claim 1, further comprising: (v), performing an alarm operation when determining that a refrigerant leak occurs in the air-cooling heat pump system. ### Claim 3 (depends on 1) The detecting method according to claim 1, wherein in the step (iii), when each leak indication parameter in the leak indication parameter set falls within the preset indication parameter interval: the compressor speed or compressor capacity; the expansion valve opening and superheat degrees; and the refrigerant level in the leak indication parameter set correspond to evaluated refrigerant leak amounts from high to low, respectively; or alternatively the compressor speed or compressor capacity; the expansion valve opening and superheat degrees; the compressor discharge pressure; and the subcooling degree in the leak indication parameter set correspond to evaluated refrigerant leak amounts from high to low, respectively. ### Claim 4 (depends on 1) The detecting method according to claim 1, wherein (ii) further comprises: comparing the compressor speed or the compressor capacity with the corresponding preset indication parameter interval when an inlet and outlet water temperature difference of a heat exchanger is less than a preset inlet and outlet water temperature difference; and one or more of: comparing the expansion valve opening and superheat degrees with the corresponding preset indication parameter intervals when the inlet and outlet water temperature difference of the heat exchanger is not less than the preset inlet and outlet water temperature difference; or comparing the refrigerant level with the corresponding preset indication parameter interval when the inlet and outlet water temperature difference of the heat exchanger is not less than the preset inlet and outlet water temperature difference; or comparing the compressor discharge pressure with the corresponding preset indication parameter interval when the inlet and outlet water temperature difference of the heat exchanger is not less than the preset inlet and outlet water temperature difference; or comparing the subcooling degree with the corresponding preset indication parameter interval when the inlet and outlet water temperature difference of the heat exchanger is not less than the preset inlet and outlet water temperature difference. ### Claim 5 (depends on 4) The detecting method according to claim 4, wherein (ii) further comprises: obtaining the expansion valve opening degree when the inlet and outlet water temperature difference of the heat exchanger is not less than the preset inlet and outlet water temperature difference; when the expansion valve opening degree reaches a preset opening degree threshold, comparing the superheat degree with the corresponding preset indication parameter interval; and when the expansion valve opening degree is less than the preset opening degree threshold, comparing the refrigerant level with the corresponding preset indication parameter interval. ### Claim 6 (depends on 4) The detecting method according to claim 4, wherein the step (ii) further comprises: obtaining a subcooling degree when the inlet and outlet water temperature difference of the heat exchanger is not less than the preset inlet and outlet water temperature difference; when the subcooling degree is not greater than a preset subcooling degree, comparing the subcooling degree with the corresponding preset indication parameter interval; or when the subcooling degree is greater than the preset subcooling degree, comparing the superheat degree and the expansion valve opening degree with the respective corresponding preset indication parameter intervals. ### Claim 7 (depends on 6) The detecting method according to claim 6, wherein (ii) further comprises: obtaining the expansion valve opening degree when the subcooling degree is greater than the preset subcooling degree; when the expansion valve opening degree reaches a preset opening degree threshold, comparing the superheat degree with the corresponding preset indication parameter interval; and when the expansion valve opening degree is less than the preset opening degree threshold, comparing the compressor discharge pressure with the corresponding preset indication parameter interval. ### Claim 8 (depends on 1) The detecting method according to claim 1, wherein after the air-cooling heat pump system operates for more than a first preset time, the step (i) is executed. ### Claim 9 (depends on 1) The detecting method according to claim 1, wherein the method further comprises, after a downtime of the air-cooling heat pump system is more than a preset time, obtaining the refrigerant level in the liquid reservoir and/or a compressor discharge pressure, and comparing the refrigerant level and/or the compressor discharge pressure with respective corresponding preset indication parameter intervals; and when the refrigerant level and/or the compressor discharge pressure fall(s) within the respective corresponding preset indication parameter intervals, determining that a refrigerant leak occurs in the air-cooling heat pump system. ### Claim 10 (depends on 1) A refrigerant leak detecting system for an air-cooling heat pump system, wherein the detecting system is used for the refrigerant leak detecting method for an air-cooling heat pump system of claim 1. ### Claim 11 (depends on 10) An air-cooling heat pump system, comprising the refrigerant leak detecting system for an air-cooling heat pump system of claim 10.