HVAC Refrigerant Leak Sensing with Periodic Sensor Flushing
Find Innovative SolutionsGenerate Solutions
Solution Overview
Problem
Refrigeration units using flammable refrigerants pose a safety risk due to the potential for dangerous leaks, which existing technologies have not adequately addressed, especially in HVAC systems where leaks can lead to fire or explosions, and existing monitoring systems struggle with accuracy and reliability.
Innovation Solution
A sensor assembly system that includes a sampling tube, a flushing tube, and a blower to continuously monitor refrigerant gases by flushing the system with ambient air, ensuring accurate detection of leaks and preventing sensor poisoning, with filters to screen out dust and moisture, and a control unit to activate the blower periodically for maintenance and safety.
Engineering Contradictions & Design Principles
Engineering Contradiction Analysis
1Measurement precision
If a sensor assembly is used to detect refrigerant gas leaks, then the detection capability is improved, but the sensor may be poisoned by accumulated gases leading to reduced reliability
Solution Approach 1:
The patent applies preliminary action by implementing a flushing tube that periodically introduces ambient air into the sensor chamber before the sensor is exposed to new gas samples. This pre-flushing action prevents gas accumulation and sensor poisoning, ensuring the sensor maintains its detection capability and reliability over extended operation periods without requiring frequent calibration or replacement.
Solution Approach 2:
The patent implements periodic action through a control unit that activates the blower at predetermined intervals to flush the sensor chamber with ambient air. This periodic flushing cycle removes accumulated refrigerant gases from the chamber, preventing sensor degradation and maintaining consistent detection performance throughout the system's operational life.
2Measurement precision
If filters are added to screen out dust and moisture, then the sensor accuracy is improved, but the device complexity increases
Solution Approach 1:
The patent applies universality by integrating multiple functions into the filter component. The filter simultaneously performs dust removal, moisture condensation, and gas flow regulation functions. By combining these functions in a single integrated component rather than using separate devices for each function, the patent improves sensor accuracy while minimizing the increase in device complexity.
3Reliability
If a flushing tube and blower are added to prevent sensor poisoning, then the reliability is improved, but the energy consumption increases
Solution Approach 1:
The patent implements periodic action by activating the blower only at predetermined intervals rather than continuously. The control unit monitors operational parameters and triggers the blower based on accumulated operation time or detected conditions, ensuring the flushing function is performed sufficiently to prevent sensor poisoning while minimizing unnecessary energy consumption during periods when flushing is not required.
Solution Approach 2:
The patent applies partial action by providing just enough flushing capability to prevent sensor poisoning without over-engineering the system. The blower is sized and controlled to deliver the minimum necessary airflow to clear the sensor chamber of accumulated gases, avoiding excessive energy consumption while maintaining adequate sensor reliability.
Applied Scientific Principles
This section explains which scientific principles are used to turn an abstract innovation direction into a practical engineering solution.
Function Achieved in This Case
The system effectively detects refrigerant leaks in HVAC units, ensuring safety by preventing the accumulation of flammable gases and reducing the risk of false positives, while maintaining sensor accuracy and reliability through continuous flushing and filtering.
Implementation Method 1
The first opening configured to allow diffusion of one or more gases therethrough
Implementation Method 2
the sampling tube is positioned exterior to the conduit and extends along a direction of a gravitation force
Implementation Method 3
the first opening comprises a filter, the filter configured to screen out dust and moisture from the one or more gases reaching the sensor assembly
Implementation Method 4
a blower disposed within interior of a conduit unit, the blower configured to be periodically activated in order to blow the ambient air into the flushing tube
Implementation Method 5
a gas sensor disposed within the chamber, the gas sensor configured to sense the one or more gases to generate a signal
Data Source
Figure 1
Figure 2
Figure 3
AI summary
Methods, apparatuses, and systems for monitoring gas leaks are disclosed herein. An example Heating Ventilation and Air Conditioning (HVAC) may comprise: a sampling tube fluidly coupled to a first opening defined in a conduit; and a sensor assembly fluidly coupled to the sampling tube. The sampling tube is positioned exterior to the conduit and extending along a direction of a gravitation force. The sensor assembly is configured to receive one or more gases that have a greater density in comparison to the ambient air and sense the one or more gases to generate a signal.