Refrigerant Leak Detection Methods in HVAC Systems

A refrigeration cycle device that improves detection of refrigerant leaks through enhanced supercooling control. The device employs a two-stage detection approach: normal operation with a controlled supercooling degree, and a second operation with a higher supercooling degree. During normal operation, the control unit maintains the standard operating conditions. However, when performing the second operation, it adjusts the supercooling degree to a higher value, triggering detection of refrigerant leaks when the discharge temperature of the compressor or outlet superheat of the evaporator exceeds predetermined thresholds. This approach enhances the early detection of leaks by leveraging the difference between normal and elevated supercooling conditions.

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Detecting refrigerant leaks in air conditioners through a novel system that integrates refrigerant detection sensors with a specially designed casing. The system features a unique casing design with a fixed panel and side panel arrangement, a heat exchanger connection plate, and a fixed water pump. The refrigerant detection area is positioned at the heat exchanger connection plate, with the detection sensor and water pump aligned vertically. This configuration enables comprehensive monitoring of refrigerant leakage through the casing and piping system, particularly at the connection points between the indoor and outdoor units.

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A refrigerant leak detection system for HVAC systems that employs a combination of temperature and humidity sensors to monitor refrigerant levels and identify potential leaks. The system uses a digital control processor to analyze temperature and humidity data from multiple sensors throughout the HVAC system, comparing it against a predefined thermal state matrix. If the system exceeds predetermined threshold values, it activates an alarm and initiates corrective actions such as isolating the affected component. This approach provides a comprehensive method for detecting refrigerant leaks in HVAC systems, particularly in systems with multiple refrigerant paths.

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Detecting refrigerant leaks in air conditioning systems using non-azeotropic refrigerants. The method involves recovering a single refrigerant component from the system, then monitoring its pressure using sensors. When the pressure drop exceeds a predetermined threshold, it indicates a refrigerant leak. This approach compensates for the non-azeotropic refrigerant's unique behavior during system shutdown, where the component composition changes and pressure dynamics are altered.

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Air conditioning system with a single shutoff valve that automatically detects refrigerant leaks in the system. The system includes an outdoor unit, multiple indoor units, refrigerant piping, and a detection device with a refrigerant sensor that monitors refrigerant flow. When the sensor detects refrigerant leakage, it triggers a relay that closes the leak notification circuit. The relay then automatically closes the cutoff valve in the refrigerant piping, eliminating the need for separate communication lines between each indoor unit.

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Refrigerant leak detection and mitigation system for HVAC systems that uses sensors to detect refrigerant leaks, identifies leak locations and severity, notifies users and third parties, and automatically escalates unaddressed leaks. The system has sensors at various HVAC components like evaporators, condensers, etc. to detect leaks. When a leak is detected, the system determines leak location and severity. It notifies users and optionally third parties. If no user response is received within a threshold time, it escalates the leak to the third party. This enables proactive leak mitigation and coordination with authorities.

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A leak detection system for HVAC and refrigeration systems that enables reliable detection of refrigerant leaks in high-temperature environments. The system employs a remote-operated sensor assembly that can be located away from high-temperature components, with a fan-driven flow path that introduces the sensor into the refrigerant circuit. The sensor's flow analysis capability ensures accurate detection of refrigerant leaks at low detection limits, while its robust design maintains reliability even in harsh environments. This approach enables universal compatibility with multiple refrigerant types, including low-GWP alternatives, without the need for specialized sensors or complex enclosures.

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Air conditioner with advanced refrigerant leakage detection that optimizes comfort while maintaining system performance. The system employs a dual-mode operation strategy, where it transitions between determining whether refrigerant leaks and operating in a comfort mode. When operating in the comfort mode, the system maintains normal indoor conditions while continuously monitoring refrigerant levels. When determining whether leaks occur, it switches to a dedicated leak detection mode, where it operates in a controlled environment to accurately identify refrigerant leaks. This dual-mode approach enables both reliable leak detection and comfort operation, ensuring both system performance and user comfort.

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A method for detecting and controlling refrigerant leaks in HVAC systems through advanced temperature monitoring. The method uses pre-recorded temperature data from prior system operation to determine current refrigerant leakage status, along with device-specific temperature parameters. It then compares measured and calculated temperature differences to determine if the system is operating within normal parameters. If deviations are detected, the method identifies the source of the leakage by analyzing temperature data from specific device locations. By controlling the refrigerant suction system based on these device-specific temperature parameters, the method prevents refrigerant circulation while maintaining system performance.

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Air conditioner with leak detection for flammable refrigerant and oil. The system employs sensors to detect refrigerant and oil leaks in the air conditioning system, with the refrigerant flow path and oil circulation sequence reversed. The sensors monitor refrigerant in the first space and oil in the second space, while the control device detects refrigerant leaks using the refrigerant detection signal and oil odor detection signal.

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Air conditioner indoor unit that enables real-time refrigerant leak detection through strategically positioned sensors. The unit features a blowout port with a detection device positioned to capture refrigerant leaks directly downstream. A second detection element, typically mounted on the heat exchange member, is positioned to detect refrigerant leaks in the heat exchanger. This configuration provides a comprehensive leak detection system that can be integrated into the unit's design while maintaining operational efficiency.

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Rooftop air conditioner with enhanced refrigerant safety through a novel design that separates the heat-source and utilization spaces while maintaining airflow. The system features a partitioned casing with a bottom plate that houses the refrigerant circuit, including a heat-source-side heat exchanger and utilization-side heat exchanger. A refrigerant leakage sensor is positioned in the utilization space to detect refrigerant leaks, and a damper connects the utilization space to the heat-source space. The system achieves this separation through a unique partition plate design that maintains airflow while preventing refrigerant from entering the building through the duct. The partition plate also includes a bottom plate with openings for supply and return air, and a damper that automatically closes when refrigerant is detected in the utilization space.

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Air conditioner with enhanced refrigerant detection and leak monitoring. The system features a blower fan that stops when the refrigerant concentration reaches a predetermined threshold, preventing false leaks. After the fan stops, a sensor continuously monitors the refrigerant concentration, enabling real-time detection of leaks even when the fan is not operating. This approach ensures accurate refrigerant leakage detection while minimizing the impact of external gas interference.

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Air conditioner with adaptive refrigerant leakage detection that matches the specific characteristics of each indoor space. The system employs a control unit that dynamically adjusts the maximum allowable refrigerant leakage amount for each indoor unit based on its unique space characteristics. This allows the air conditioner to accurately detect and prevent refrigerant leaks that could compromise performance or safety in specific environments. The system includes a refrigerant leak detection unit that monitors refrigerant flow into the indoor space, and a control unit that blocks refrigerant flow when leakage exceeds the determined maximum allowable amount. The control unit can be configured to select different reference leakage amounts for each indoor unit, enabling precise adaptation to different space conditions.

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Air conditioner with enhanced refrigerant leak detection. The system employs a relay-based control system that separates refrigerant leakage into distinct paths, with each path being isolated through a relay valve. The system includes a relay unit with individual valves controlling the indoor expansion and gas valves, which are then connected to the refrigerant lines. A temperature sensor network monitors refrigerant temperatures in the indoor units to detect continuous leakage. The system's control logic switches the valves based on refrigerant leakage detection, allowing continuous operation of the indoor units while preventing refrigerant flow through the isolated paths.

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A medium to low global warming potential (GWP) refrigerant leak detection system for air conditioning systems. The system employs a dual-mode sensor configuration that operates in both a baseline response mode and a leak detection mode. The baseline response mode provides a stable reference signal for continuous monitoring of refrigerant concentrations, while the leak detection mode rapidly identifies and indicates refrigerant leaks through binary output. The system enables targeted fan and vent control based on the binary output, ensuring effective refrigerant leak mitigation while minimizing system disruption.

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Air-conditioning system with leak detection and automatic control that balances comfort and safety through refrigerant monitoring and protection. The system features a refrigerant circuit with leak detection through temperature monitoring, a leak detection and cutoff device, and a control device that combines these functions to prevent refrigerant loss while maintaining system performance.

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A refrigerant leak detection and mitigation system for HVAC systems that can detect and respond to refrigerant leaks without directly sensing the leaked refrigerant. The system uses sensors to monitor conditions like icing, subcooling, and superheat in the HVAC components. A controller analyzes the sensor data to determine the probability of a refrigerant leak. If the leak probability exceeds thresholds, the controller takes actions like opening dampers or activating fans to dissipate any leaked refrigerant from the system. This allows indirect detection of leaks by monitoring conditions that indicate leaks, rather than sensing the leaked refrigerant itself.

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Detecting gas leaks in refrigeration systems using non-azeotropic refrigerants. The method involves measuring the characteristic changes of the refrigerant composition when a gas leak occurs, particularly in non-azeotropic refrigerants like R407H. By monitoring the solution temperature and pressure of the saturated liquid, the system determines the exact amount of refrigerant that has leaked. This enables precise detection and restoration of the refrigerant composition, ensuring optimal operation even in situations where maintenance is limited.

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Air harmony device with enhanced refrigerant leak detection and control. The device incorporates a refrigerant detection system that automatically identifies refrigerant leaks through advanced concentration monitoring. When a leak is detected, the system triggers an alarm, interrupting the refrigerant supply and ventilating the space to prevent further contamination. The system employs a threshold-based approach to rapidly determine refrigerant concentration levels, enabling immediate intervention when leaks occur. This approach eliminates the need for traditional chemical-based detection methods, providing a more reliable and proactive approach to refrigerant leak detection.

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