# US 11,441,820 B2 · Refrigerant leak detection system > Agents: this data is available as JSON from the patentgrep API and MCP server — see https://patentgrep.com/llms.txt - Number: US 11,441,820 B2 - Document ID: US11441820B2 - Status: Granted - Kind: B2 - Application number: 17/254,746 - Filed: 2019-09-05 - Published: 2021-09-02 - Granted: 2022-09-13 - Earliest claimed: 2018-09-06 - Assignees: Carrier Corporation - Applicants: Carrier Corporation - Inventors: Paul V. Weyna; Jason D. Scarcella; Mark J. Perkovich; Lei Chen; Hai Tian - Web page: https://patentgrep.com/patent/US11441820B2 ## CPC - F25B 1/00: Compression machines, plants or systems with non-reversible cycle (F25B3/00, F25B5/00, F25B6/00, F25B7/00, F25B9/00 take precedence) - B60H 1/00485: {Valves for air-conditioning devices, e.g. thermostatic valves} - B60H 1/3205: {Control means therefor} - B60H 1/3225: {characterised by safety arrangements, e.g. compressor anti-seizure means or by signalling devices} - B60H 1/3227: {characterised by the arrangement or the type of heat exchanger, e.g. condenser, evaporator (condensed liquid drainage means B60H1/3233)} - B60H 1/3232: {particularly adapted for load transporting vehicles (B60H1/3226 takes precedence)} - F25B 41/34: with the valve member being actuated by electric means, e.g. by piezoelectric actuators - F25B 41/39: Dispositions with two or more expansion means arranged in series, i.e. multi-stage expansion, on a refrigerant line leading to the same evaporator - F25B 49/02: for compression type machines, plants or systems - B60H 2001/325: {of the refrigerant at a compressing unit} - B60H 2001/3252: {of the refrigerant at an evaporating unit} - B60H 2001/3272: {to control the revolving speed of a compressor} - F25B 2400/16: Receivers - F25B 2500/222: Detecting refrigerant leaks - F25B 2600/112: of evaporator fans - F25B 2600/2513: Expansion valves - F25B: REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS - B60H: ARRANGEMENTS OF HEATING, COOLING, VENTILATING OR OTHER AIR-TREATING DEVICES SPECIALLY ADAPTED FOR PASSENGER OR GOODS SPACES OF VEHICLES ## Abstract A method of mitigating refrigerant leaks within a refrigeration system that includes: detecting a leak of a refrigerant from a refrigeration system; closing a first valve to inhibit a fluid flow of the refrigerant between an evaporator and a condenser fluidly connected to the evaporator; and operating a compressor to direct another fluid flow of the refrigerant from the evaporator to the compressor. ## Claims ### Claim 1 A refrigeration system, comprising: a compressor driven by a power source, the compressor having a compressor outlet and a compressor inlet; a condenser having a condenser inlet, fluidly connected to the compressor outlet, and a condenser outlet; an evaporator having an evaporator inlet, fluidly connected to the condenser outlet through a first valve movable between an open position and a closed position, and a evaporator outlet fluidly connected to the compressor inlet; a leak sensor arranged to provide a signal indicative of a refrigerant; a controller in communication with the first valve and the compressor, the controller being arranged to receive the signal and programmed to command the first valve to move towards the closed position, responsive to the signal being indicative of the refrigerant; a main heat valve fluidly connecting the compressor outlet and the condenser inlet, the main heat valve being movable between an open position and a closed position, wherein the controller is programed to command the main heat valve to move to the open position; and a hot gas valve fluidly connecting the compressor and the evaporator inlet, the hot gas valve being movable between an open position and a closed position, wherein the controller is programed to command the hot gas valve to move to the closed position prior to commanding the first valve to move towards the closed position. ### Claim 2 (depends on 1) The refrigeration system of claim 1, wherein the controller is further programmed to output for display an indicator. ### Claim 3 (depends on 1) The refrigeration system of claim 1, wherein the controller is further programmed to operate the compressor such that refrigerant within the evaporator is directed towards the compressor. ### Claim 4 (depends on 3) The refrigeration system of claim 3, wherein the controller is further programmed to command the compressor to stop operating, responsive to a fluid pressure between the evaporator outlet and the compressor outlet being less than a threshold pressure. ### Claim 5 (depends on 3) The refrigeration system of claim 3, further comprising: a receiver having a receiver inlet fluidly connected to the condenser outlet, wherein the receiver is arranged to receive the refrigerant from the condenser. ### Claim 6 (depends on 1) The refrigeration system of claim 1, wherein the controller is arranged to receive the signal and programmed to command the first valve to move towards the closed position, responsive to the signal being indicative of a selected concentration of the refrigerant. ### Claim 7 (depends on 1) The refrigeration system of claim 1, wherein the controller is further programmed to operate an evaporator fan when refrigerant is detected. ### Claim 8 (depends on 1) The refrigeration system of claim 1, further comprising: a second valve fluidly connecting the evaporator outlet and the compressor inlet, the second valve being movable between an open position and a closed position. ### Claim 9 (depends on 8) The refrigeration system of claim 8, wherein the controller is further programmed to operate the compressor such that refrigerant within the evaporator is directed towards the compressor until a suction pressure measurement proximate an inlet of the compressor is less than an ambient pressure. ### Claim 10 (depends on 9) The refrigeration system of claim 9, wherein the controller is programmed to command the second valve to move towards the closed position when the suction pressure measurement proximate an inlet of the compressor is less than an ambient pressure. ### Claim 11 (depends on 8) The refrigeration system of claim 8, wherein the evaporator and the leak sensor are located within a conditioned space of the refrigeration system, and wherein the first valve and the second valve are located outside of the conditioned space. ### Claim 12 A method of mitigating refrigerant leaks within a refrigeration system, comprising: detecting a leak of a refrigerant from a refrigeration system; closing a first valve to inhibit a fluid flow of the refrigerant between an evaporator and a condenser fluidly connected to the evaporator; operating a compressor to direct another fluid flow of the refrigerant from the evaporator to the compressor; directing the fluid flow of the refrigerant from the compressor to a receiver; and closing a second valve to inhibit a fluid flow of the refrigerant between the receiver and the condenser. ### Claim 13 (depends on 12) The method of claim 12, further comprising: operating an evaporator fan that is disposed proximate the evaporator. ### Claim 14 (depends on 12) The method of claim 12, further comprising: stopping operation of the compressor, responsive to an evaporator pressure being less than a threshold pressure. ### Claim 15 (depends on 14) The method of claim 14, further comprising: closing a second valve to inhibit a fluid flow of the refrigerant between the evaporator and the compressor. ### Claim 16 A method of mitigating refrigerant leaks within a refrigeration system, comprising: detecting a leak of a refrigerant from a refrigeration system; closing a first valve to inhibit a fluid flow of the refrigerant between an evaporator and a condenser fluidly connected to the evaporator; operating a compressor to direct another fluid flow of the refrigerant from the evaporator to the compressor; opening a main heat valve to allow a fluid flow of the refrigerant between the compressor and the condenser; and closing a hot gas valve to inhibit a fluid flow of the refrigerant between the compressor and the evaporator.