Gas detector test and calibration method and apparatus

A detector testing system for testing a gas detector used in a heating, ventilation, and air conditioning, or refrigeration (HVAC\R) system including: a testing chamber configured to receive the gas detector through an orifice in the detector testing system, the testing chamber being configured to at least partially enclose the gas detector within the testing chamber; a receiving port fluidly connected to the testing chamber; and a target gas cartridge fluidly connected to the receiving port, wherein the target gas cartridge contains a known concentration of a target gas, wherein the receiving port is configured to deliver the target gas to the testing chamber.

BACKGROUND

The subject matter disclosed herein generally relates to the gas sensing, and more particularly to an apparatus and method for testing gas sensors and detection systems.

Products may be shipped or stored within a conditioned space, such as a container, truck or trailer. These conditioned spaces utilize a refrigeration unit that circulates cooled air inside the interior volume. In many cases, the refrigeration unit uses a refrigeration cycle to cool the air. Refrigerant from the refrigeration unit may leak and thus it needs to be verified that gas detection systems are operating correctly to successfully detect the leak.

BRIEF SUMMARY

According to one embodiment, a detector testing system for testing a gas detector used in a heating, ventilation, and air conditioning, or refrigeration (HVAC\R) system. The detector testing system including: a testing chamber configured to receive the gas detector through an orifice in the detector testing system, the testing chamber being configured to at least partially enclose the gas detector within the testing chamber; a receiving port fluidly connected to the testing chamber; and a target gas cartridge fluidly connected to the receiving port, wherein the target gas cartridge contains a known concentration of a target gas, wherein the receiving port is configured to deliver the target gas to the testing chamber.

In addition to one or more of the features described above, or as an alternative, further embodiments may include a door configured to seal against the orifice and fully enclose the gas detector within the testing chamber.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the orifice is configured to seal against a mounting surface of the HVAC/R system and enclose the gas detector within the testing chamber.

In addition to one or more of the features described above, or as an alternative, further embodiments may include a communication device in electronic communication with a communication device of the gas detector.

In addition to one or more of the features described above, or as an alternative, further embodiments may include a display device configured to display detector readings detected by the gas detector.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the target gas is a refrigerant.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the target gas is a mildly flammable refrigerant.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the target gas is an A2 refrigerant, A2L refrigerant, or an A3 refrigerant.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the known concentration of the target gas within the target gas cartridge is a lower flammability limit of the target gas.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the target gas within the target gas cartridge is diluted to a lower flammability limit of the target gas prior to the target gas entering the testing chamber.

In addition to one or more of the features described above, or as an alternative, further embodiments may include: an environmental control configured to adjust an environmental conditions within the testing chamber; and an environmental sensor configured to detect the environmental condition within the testing chamber.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the environmental condition.

In addition to one or more of the features described above, or as an alternative, further embodiments may include: a communication device in electronic communication with a communication device of the gas detector, wherein the communication device is configured to received readings detected by the gas detector and transmit the readings to a cloud server.

In addition to one or more of the features described above, or as an alternative, further embodiments may include a communication device in electronic communication with a communication device of the gas detector, wherein the communication device is configured to communicate with the gas detector for recalibration of the gas detector.

According to another embodiment, a method of testing a gas detector for a heating, ventilation, and air conditioning, or refrigeration (HVAC/R) system is provided. The method including: inserting the gas detector through an orifice in a detector testing system and at least partially into a testing chamber within the detector testing system, the testing chamber being configured to at least partially enclose the gas detector within the testing chamber; sealing the testing chamber off from external environments; providing a target gas into the testing chamber; and receiving one or more readings from HVAC/R system.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that sealing the testing chamber off from external environments further includes: removing the gas detector from the HVAC/R system; inserting the gas detector fully into the testing chamber; and closing a door of the testing chamber, the door being configured to seal against the orifice and fully enclose the gas detector within the testing chamber.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that sealing the testing chamber off from external environments further includes: sealing the orifice against a mounting surface of the HVAC/R system, the gas detector remaining attached to the mounting surface; and enclosing the gas detector within the testing chamber.

In addition to one or more of the features described above, or as an alternative, further embodiments may include: displaying the one or more detector readings detected by the gas detector within the detector testing system.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the target gas is a refrigerant.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the target gas is a flammable refrigerant.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the target gas is an A2 refrigerant, A2L refrigerant, or an A3 refrigerant.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that prior to providing the target gas into the testing chamber, the method further includes: diluting the target gas to a lower flammability limit of the target gas prior to the target gas entering the testing chamber.

In addition to one or more of the features described above, or as an alternative, further embodiments may include: detecting an environmental condition within the testing chamber using an environmental sensor; and adjusting the environmental condition within the testing chamber using an environmental control.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that receiving readings from the gas detector; and transmitting the readings to a cloud server.

In addition to one or more of the features described above, or as an alternative, further embodiments may include: receiving readings from the gas detector; determining a recalibration of the gas detector is required in response to the readings; and transmitting the calibration parameters or adjustments for recalibration of the gas detector to the gas detector.

In addition to one or more of the features described above, or as an alternative, further embodiments may include: receiving response data from the HVAC/R system; and determining whether the HVAC/R system has performed or is performing an isolation and pump down procedure following the introduction of the target gas into the testing chamber.

In addition to one or more of the features described above, or as an alternative, further embodiments may include: transporting the target gas from the testing chamber to a target gas tank.

According another embodiment, detector testing system for testing a gas detector used in a heating, ventilation, and air conditioning, or refrigeration (HVAC\R) system is provided. The detector testing system including: a testing cup having a cup mounting surface with an orifice; a testing chamber extending from the orifice of the cup mounting surface into the testing cup; a target gas delivery hose fluidly connected to the testing chamber; and a target gas tank fluidly connected to the testing chamber through the target gas delivery hose, wherein the target gas delivery hose is configured to deliver a target gas from the target gas tank to the testing chamber.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the cup mounting surface is configured to seal against a mounting surface of the HVAC/R system and enclose the gas detector within the testing chamber.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the target gas is a refrigerant.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the target gas is a mildly flammable refrigerant.

In addition to one or more of the features described above, or as an alternative, further embodiments may include that the target gas is an A2 refrigerant, A2L refrigerant, or an A3 refrigerant.

In addition to one or more of the features described above, or as an alternative, further embodiments may include: a target gas metering component located within the target gas delivery hose interposed between the testing chamber and the target gas tank.

In addition to one or more of the features described above, or as an alternative, further embodiments may include: a target gas return hose fluidly connecting the testing chamber to the target gas tank; and a target gas reclaim component located within the target gas return hose interposed between the testing chamber and the target gas tank.

DETAILED DESCRIPTION

FIGS.1-2schematically illustrates a detector testing system100configured to test a gas detector200. The gas detector200may contain various components that are tested by the detector testing system100, such as for example gas sensors, diagnostic algorithms, and mitigation mechanisms such as lights, relays and switches. It should be appreciated that, although particular systems are separately defined in the schematic block diagrams, each or any of the systems may be otherwise combined or separated via hardware and/or software. The gas detector200may be used in a heating, ventilation, and air conditioning or refrigeration (HVAC/R) system300to detect a target gas. In an embodiment, the target gas is a refrigerant. In an embodiment, the target gas is a flammable and/or a mildly flammable refrigerant. In one embodiment, a mildly flammable refrigerant may be defined as a refrigerant having a greater than 0.3 kg/m3, a heat of combustion less than 19,000 kj/kg, and/or a burning velocity of less than 10 cm/s. In an embodiment, the mildly flammable refrigerant may be A2L refrigerant. An A2L refrigerant may include but is not limited to R32, R1234yf, R-1234ze(E), R134A, R454A, and R454B. In another embodiment, the target gas may be a higher flammability refrigerant, such as, for example an A3 refrigerant. In another embodiment, the target gas is an A2 refrigerant, A2L refrigerant, or an A3 refrigerant. An A2 refrigerant may include but is not limited to R-152a. An A3 refrigerant may include but is not limited to R-290 (Propane) and R-600a (isobutene).

The HVAC/R system300may be a commercial or residential stationary HVAC system or a transport or stationary refrigeration (R) system. The gas detector200may be utilized in operative association with a transport HVAC/R system, such as, for example, a refrigerated truck, a refrigerated trailer, or a refrigerated container. The gas detector200may also be utilized in operative association with a stationary HVAC/R system, such as, for example, refrigerated cabinets (e.g., self-serve refrigerated grocery cabinets with and without doors). In the transport refrigeration system or the commercial refrigeration system, the gas detector200may be used as part of a refrigeration control system to adjust environmental conditions of the perishable goods (e.g., cargo/stock/inventory) in order to control or influence the control of ventilation, humidity, air temperature, and/or contaminant scrubbing systems. In one embodiment, the gas detector200may be used to activate ventilation to lower the target gas concentration around the gas detector200, or to alert personnel to the presence of the target gas, or potential damage to property or perishable goods. In another embodiment, the gas detector200may be utilized independent of a corresponding refrigeration system or commercial refrigeration system to alert personnel to potential damage to perishable goods, alert personnel to the presence of the target gas, and/or to increase or decrease ventilation rates.

The detector testing system100may be separate and apart from the gas detector200and may be utilized to test the gas detector200periodically or intermittently, as required. The detector testing system100may be brought onsite to test the gas detector200. The gas detector200may be removed from the HVAC/R system300and tested within the detector testing system100or the detector testing system100may be brought to the HVAC/R system300to test the gas detector200while remaining installed in the HVAC/R system300, as described herein.

The detector testing system100includes a testing chamber110capable of fully and/or partially enclosing the gas detector200. In the embodiment illustrated inFIG.1, the gas detector200is removed from the HVAC/R system300and tested within the detector testing system100, which fully encloses the gas detector200. The gas detector200may be removed from the HVAC/R system300and placed within the testing chamber110. The detector testing system100may include a door112to environmentally seal the testing chamber110from external environments210, thus creating a controlled environment within the testing chamber110. The door112is configured to seal against an orifice118of the detector testing system100, which opens up into the testing chamber110.

In the embodiment illustrated inFIG.2, the gas detector200is not removed from a mounting surface302of the HVAC/R system300and tested within the detector testing system100while still being mounted to the mounting surface302. As shown inFIG.2, the gas detector200is inserted into an orifice118of the detector testing system100. The orifice118opens up into the testing chamber110. The orifice118is configured to seal against the mounting surface302of the HVAC/R system300, while the testing chamber110encloses the gas detector200. The orifice118sealing against the mounting surface302of the HVAC/R system300environmentally seals (i.e., isolates) the gas detector200within the testing chamber110and prevents gas leakage between the testing chamber110and an external environment210outside of the testing chamber110.

When the gas detector200is sealed within the testing chamber110, the detector testing system100is configured to emit a known concentration of the target gas into the testing chamber110to test a state of health of the gas detector200. The detector testing system100may be in wired and/or wireless communication with the gas detector200when the gas detector200is located within the testing chamber110to receive detector readings from the gas detector200. The detector testing system100may include a communication device114and the gas detector200may include a communication device114. In one embodiment, the communication device214of the gas detector200may be hardwired to the communication device114of the detector testing system100through a removable connecting wire (not shown). In another embodiment, the communication device214of the gas detector200may be in wireless communication with the communication device114of the detector testing system100through a short-range wireless transmissions, such as, for example, Bluetooth, Wi-Fi, Infrared, etc.

In one embodiment, a memory506of a controller502of the detector testing system100or any other memory device within the detector testing system100may be utilized to locally store testing data, including, but not limited to, building name, building number, room number, HVAC/R identification number, station number, time, test number, target gas name, target gas concentration, detector name, detector location, detector baseline, readings from the gas detector200, detector response as function of time, the known concentration of the target gas within the target gas cartridge150, the concentration of target gas delivered into the testing chamber110, the humidity within the testing chamber110, and the temperature within the testing chamber110, and the like.

In one embodiment, the controller502of the detector testing system100may be configured to locally analyze the testing data, determine a pass or fail decision for the gas detector200, and display the pass or fail decision back on the detector testing system100.

In another embodiment, the communication device214of the gas detector200may be in wireless communication with a cloud server900through a wireless transmissions, such as, for example, Bluetooth, Wi-Fi, Infrared, cellular, satellite, or other network communication. The communication device214may be configured to transmit the testing data to the cloud server900. The cloud server900may be configured to analyze the testing data, determine a pass or fail decision for the gas detector200, and transmit the pass or fail decision back to the detector testing system100for local display.

In another embodiment, the communication device214of the gas detector200may be in wired communication with another device, such as, for example, for example a phone, a laptop. In addition to determining a pass or fail, the controller502and/or the cloud server900may alternatively determine that the gas detector200needs to be recalibrated using the detector testing system100. The communication device114of the detector testing system100may be in wireless communication with the communication device214of the gas detector200through a short-range wireless transmissions, such as, for example, Bluetooth, Wi-Fi, Infrared, etc. The communication device114of the detector testing system100may be in wired communication with the communication device214of the gas detector200through a USB cable, Ethernet, fiber-optics, etc. Through the communication devices114,214, the detector testing system100may be able to pass to the gas detector200calibration parameters or adjustments thereto for recalibration of the gas detector200, which may be an automatic process. For example, once connected with the gas detector200, the detector testing system100can pair with the gas detector200to start a calibration test where it delivers a known concentration of target gas into the testing chamber110. Upon receiving the readings from the gas detector200in response to the target gas then the detector testing system100can send updated calibration parameters to the gas detector200and then rerun the test to confirm that the gas detector200has been successfully recalibrated. This recalibration process can be done at various temperature levels and humidity levels as discussed herein.

The controller502may be configured to control entry of the target gas into the testing chamber110. The controller502may be an electronic controller including a processor504and an associated memory506comprising computer-executable instructions that, when executed by the processor504, cause the processor504to perform various operations. The processor504may be, but is not limited to, a single-processor or multi-processor system of any of a wide array of possible architectures, including field programmable gate array (FPGA), central processing unit (CPU), application specific integrated circuits (ASIC), digital signal processor (DSP) or graphics processing unit (GPU) hardware arranged homogenously or heterogeneously. The memory506may be but is not limited to a random access memory (RAM), read only memory (ROM), or other electronic, optical, magnetic or any other computer readable medium.

The target gas may be received from a target gas cartridge150. The target gas cartridge150may include an output port152that fluidly connects to a receiving port102of the detector testing system100. The receiving port102is fluidly connected to the testing chamber110and configured to deliver the target gas into the testing chamber110. The target gas cartridge150contains a known concentration of the target gas, such as, for example, 0%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%, or any concentration therebetween. In one embodiment, the target gas cartridge150may contain a known concentration of the target gas equal to 100% and the detector testing system100may include a flow meter to adjust flow of the target gas from the target gas cartridge150into the testing chamber110.

Although only one is shown, the detector testing system100may include multiple receiving ports102that connect to multiple target gas cartridges150and/or a dilution gas cartridge160. In the event multiple target gas cartridges150are utilized, each of the multiple target gas cartridges150may contain a different known concentration of the target gas. The dilution gas cartridge160may also include an output port162that fluidly connects to a receiving port102of the detector testing system100. In an embodiment, the detector testing system100may include a flow meter to help dilute the target gas. The flow meter is not shown for simplification of illustration.

In one embodiment, the detector testing system100may introduce the target gas from the target gas cartridge150directly into the testing chamber110without diluting the target gas received from the target gas cartridge150. In another embodiment, the detector testing system100may dilute the target gas received from the target gas cartridge150prior to entering into the testing chamber110using external air or a gas from the dilution gas cartridge160. In an embodiment, the known concentration of the target gas within the target gas cartridge150is a lower flammability limit (LFL) of the target gas. In another embodiment, the known concentration of the target gas within the target gas cartridge150may be diluted to the LFL of the target gas prior to entering the testing chamber110.

The detector testing system100may also be configured to test a responsiveness of the gas detector200to a non-target gas. The non-target gas may be received from a non-target gas cartridge170. The non-target gas cartridge170may include an output port172that fluidly connects to a receiving port102of the detector testing system100. The non-target gas cartridge170contains a known concentration of a non-target gas, such as, for example, 0%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%, or any concentration therebetween. In one embodiment, the detector testing system100may introduce the non-target gas from the non-target gas cartridge170directly into the testing chamber110without diluting the non-target gas received from the non-target gas cartridge170. In another embodiment, the detector testing system100may dilute the non-target gas received from the non-target gas cartridge170prior to entering into the testing chamber110using external air or a gas from a dilution gas cartridge160. Advantageously, utilizing a non-target gas allows the detector testing system100to test cross sensitivity of the gas detector200to gases other than the target gas.

The detector testing system100may also be configured to test a responsiveness of the gas detector200to a target gas at various temperatures and humidity levels. The detector testing system100may include environmental controls510configured to adjust the environmental conditions within the testing chamber110and environmental sensors520configured to detect the environmental conditions within the testing chamber110. The environmental controls510may include but are not limited to a heater510aand a humidifier510b. The environmental sensors520include but are not limited to a temperature sensor520aand a humidity sensor520b. Advantageously, by including environmental controls510and environmental sensors520, the detector testing system100could test accuracy of the gas detectors200at multiple other temperature or humidity conditions rather than at the one environmental condition that occurred during the test. The controller502of the detector testing system100would be configured to establish environmental testing conditions within the testing chamber110using the environmental controls510and the environmental sensors520prior to reading the gas detector200output and comparing it to the target gas composition. Advantageously, adjusting the temperature and the humidity within the testing chamber110could be used to test gas detectors200having multipoint calibrations over a range of temperature and humidity levels.

The detector testing system100may also include a display device120configured to display detector readings from the gas detector200, the concentration of the target gas or non-target gas being detected by the gas detector200enclosed within the testing chamber110, a temperature within the testing chamber110, and humidity conditions within the testing chamber110. The display device120may include detector readings such as whether the sensor within the gas detector200being tested passes the accuracy level required or not (e.g., pass or no pass), whether relays or other system-level mitigation mechanisms including in the gas detector200, such as, for example, lights or switches are operating or operating correctly. The detector testing system100may also include different relay indicator lights130that may illuminate when different rely signals are activated by the gas detector200in response to a target gas or non-target gas. For example, when the gas detector200detects a target gas of a certain concentration then the gas detector200may produce a rely signal to the HVAC/R system300to perform a task (e.g., switches, fan on/off switches, activate an alarm, shut off the HVAC/R system, etc.) and the rely signal from the gas detector200will be communicated to the detector testing system100through the communication devices114,214and a relay indicator light130may illuminate, and the results may be displayed in the display device120.

Referring now toFIG.3, with continued reference toFIGS.1-2, a flow chart of a method400of testing the gas detector200for an HVAC/R system300is illustrated, in accordance with an embodiment of the present disclosure. In an embodiment, the method400is performed by the detector testing system100. At block404, the gas detector200is inserted through an orifice118in a detector testing system100and at least partially into a testing chamber110within the detector testing system100. The testing chamber110being configured to at least partially enclose the gas detector200within the testing chamber110. In an embodiment, the testing chamber110is configured to at least totally or completely enclose the gas detector200within the testing chamber110.

At block406, the testing chamber110is sealed off from external environments210external to the testing chamber110and/or the detector testing system100. The testing chamber110may be sealed off from external environments210by: removing (e.g., detaching) the gas detector200from the HVAC/R system300; inserting the gas detector200fully into the testing chamber110; and closing a door112of the testing chamber110. The door112is configured to seal against the orifice118and fully enclose the gas detector200within the testing chamber110. The testing chamber110may also be sealed off from external environments210by: sealing the orifice118against a mounting surface302of the HVAC/R system300while the gas detector200remains attached to the mounting surface302; and partially enclosing the gas detector200within the testing chamber110.

At block408, a target gas is provided into the testing chamber110from a target gas cartridge150containing a known concentration of the target gas. In an embodiment, the target gas is a refrigerant. In another embodiment, the target gas is a mildly flammable refrigerant. In another embodiment, the target gas is an A2 refrigerant, A2L refrigerant, or an A3 refrigerant. In another embodiment, the known concentration of the target gas within the target gas cartridge is a lower flammability limit of the target gas.

At block410, one or more readings are received from the gas detector200. The method400may further comprising displaying the one or more detector readings detected by the gas detector200either through the display device120or relay indicator lights130. Additionally, the method400may further comprise: diluting the target gas to a lower flammability limit of the target gas prior to entering the testing chamber110.

The method400may also comprise: detecting an environmental condition within the testing chamber110using an environmental sensor520adjusting the environmental condition within the testing chamber110using an environmental control510. The method400may further comprise: receiving readings from the gas detector200and transmitting the readings to a cloud server900. The method400may also further comprise: receiving readings from the gas detector200; determining a recalibration of the gas detector200is required in response to the readings; and transmitting the calibration parameters or adjustments for recalibration of the gas detector to the gas detector200.

While the above description has described the flow processes ofFIG.3in a particular order, it should be appreciated that unless otherwise specifically required in the attached claims that the ordering of the steps may be varied.

FIG.4schematically illustrates a detector testing system600configured to test a gas detector200and an associated HVAC/R system300. The gas detector200may contain various components that are tested by the detector testing system600, such as for example gas sensors, diagnostic algorithms, and mitigation mechanisms such as lights, relays and switches. It should be appreciated that, although particular systems are separately defined in the schematic block diagrams, each or any of the systems may be otherwise combined or separated via hardware and/or software. The gas detector200is used in the HVAC/R system300to detect a target gas. In an embodiment, the target gas is a refrigerant. In an embodiment, the target gas is a flammable and/or a mildly flammable refrigerant. In one embodiment, a mildly flammable refrigerant may be defined as a refrigerant having a greater than 0.3 kg/m3, a heat of combustion less than 19,000 kj/kg, and/or a burning velocity of less than 10 cm/s. In an embodiment, the mildly flammable refrigerant may be A2L refrigerant. An A2L refrigerant may include but is not limited to R32, R1234yf, R-1234ze(E), R134A, R454A, and R454B. In another embodiment, the target gas may be a higher flammability refrigerant, such as, for example an A3 refrigerant. In another embodiment, the target gas is an A2 refrigerant, A2L refrigerant, or an A3 refrigerant. An A2 refrigerant may include but is not limited to R-152a. An A3 refrigerant may include but is not limited to R-290 (Propane) and R-600a (isobutene).

The HVAC/R system300may be a commercial or residential stationary HVAC system or a transport or stationary refrigeration (R) system. The gas detector200may be utilized in operative association with a transport HVAC/R system, such as, for example, a refrigerated truck, a refrigerated trailer, or a refrigerated container. The gas detector200may also be utilized in operative association with a stationary HVAC/R system, such as, for example, refrigerated cabinets (e.g., self-serve refrigerated grocery cabinets with and without doors). In the transport refrigeration system or the commercial refrigeration system, the gas detector200may be used as part of a refrigeration control system to adjust environmental conditions of the perishable goods (e.g., cargo/stock/inventory) in order to control or influence the control of ventilation, humidity, air temperature, and/or contaminant scrubbing systems. In one embodiment, the gas detector200may be used to activate ventilation to lower the target gas concentration around the gas detector200, or to alert personnel to the presence of the target gas, or potential damage to property or perishable goods. In another embodiment, the gas detector200may be utilized independent of a corresponding refrigeration system or commercial refrigeration system to alert personnel to potential damage to perishable goods, alert personnel to the presence of the target gas, and/or to increase or decrease ventilation rates.

The detector testing system600may be separate and apart from the gas detector200and may be utilized to test the gas detector200periodically or intermittently, as required. The detector testing system600may be brought onsite to test the gas detector200. The detector testing system600may be brought to the HVAC/R system300to test the gas detector200while remaining installed in the HVAC/R system300, as described herein.

The detector testing system600includes a testing cup608with a testing chamber610capable of partially enclosing the gas detector200. The testing chamber610originates on a cup mounting surface612of the testing cup608and extends into the testing cup608, as illustrated inFIG.4.

In the embodiment illustrated inFIG.4, the gas detector200is not removed from a mounting surface302of the HVAC/R system300but rather gas detector200is tested within the testing chamber610of the testing cup608while still being mounted to the mounting surface302. As shown inFIG.4, the gas detector200is inserted into an orifice618of the detector testing system600. The orifice618opens up into the testing chamber610. The cup mounting surface612is configured to seal against the mounting surface302of the HVAC/R system300, while the testing chamber610encloses the gas detector200. The cup mounting surface612sealing against the mounting surface302of the HVAC/R system300environmentally seals (i.e., isolates) the gas detector200within the testing chamber610and prevents gas leakage between the testing chamber610and an external environment210outside of the testing chamber610.

When the gas detector200is sealed within the testing chamber610, the detector testing system600is configured to emit a known concentration of the target gas into the testing chamber610to test a state of health of the gas detector200and a response of the HVAC/R system300.

The detector testing system600may be in wired and/or wireless communication with the HVAC/R system300when the gas detector200is located within the testing chamber610to response data of the HVAC/R system300. The detector testing system600may include a communication device714and the HVAC/R system300may include a communication device314. In one embodiment, the communication device314of the HVAC/R system300may be hardwired to the communication device714of the detector testing system600through a removable connecting wire (not shown). In another embodiment, the communication device314of the HVAC/R system300may be in wireless communication with the communication device714of the detector testing system600through a short-range wireless transmissions, such as, for example, Bluetooth, Wi-Fi, Infrared, etc. Alternatively, there may be no communication between the detector testing system600and the HVAC/R system300, a technician may verify a response of the HVAC/R system300to testing by the detector system testing system600.

In one embodiment, a memory706of a controller702of the detector testing system600or any other memory device within the detector testing system600may be utilized to locally store testing data, including, but not limited to, building name, building number, room number, station number, time, test number, target gas name, target gas concentration, detector name, detector location, detector baseline, readings from the gas detector200, detector response as function of time, the known concentration of the target gas within the target gas tank750, the concentration of target gas delivered into the testing chamber610, the humidity within the testing chamber610, and the temperature within the testing chamber610, and the like. In an embodiment, the controller702is configured to dispense a correct quantity of target gas for testing.

In one embodiment, the controller702of the detector testing system600may be configured to locally analyze the testing data, determine a pass or fail decision for the gas detector200, and display the pass or fail decision back on the detector testing system600. In another embodiment, the communication device314may be in wireless communication with a cloud server900through a wireless transmissions, such as, for example, Bluetooth, Wi-Fi, Infrared, cellular, satellite, or other network communication. The communication device314may be configured to transmit the testing data to the cloud server900. The cloud server900may be configured to analyze the testing data, determine a pass or fail decision for the gas detector200, and transmit the pass or fail decision back to the detector testing system600for local display. Testing data may be downloaded from the HVAC/R system300to the controller702or any other computing device for analysis.

In addition to determining a pass or fail, the controller702and/or the cloud server900may alternatively determine that the gas detector200needs to be recalibrated using the detector testing system600. The communication device114of the detector testing system100may be in wireless communication with the communication device214of the gas detector200through a short-range wireless transmissions, such as, for example, Bluetooth, Wi-Fi, Infrared, etc. The communication device114of the detector testing system100may be in wired communication with the communication device214of the gas detector200through a USB cable, Ethernet, fiber-optics, etc. Through the communication devices714,214, the detector testing system600may be able to pass to the gas detector200calibration parameters or adjustments thereto for recalibration of the gas detector200, which may be an automatic process. For example, once connected with the gas detector200, the detector testing system600can pair with the gas detector200to start a calibration test where it delivers a known concentration of target gas into the testing chamber610. Upon receiving the readings from the gas detector200in response to the target gas then the detector testing system600can send updated calibration parameters to the gas detector200and then rerun the test to confirm that the gas detector200has been successfully recalibrated.

The controller702may be configured to control entry of the target gas into the testing chamber610using a target gas metering component760or removal of the target gas from the testing chamber610using a target gas reclaim component770. The controller702may be an electronic controller including a processor704and an associated memory706comprising computer-executable instructions that, when executed by the processor704, cause the processor704to perform various operations. The processor704may be, but is not limited to, a single-processor or multi-processor system of any of a wide array of possible architectures, including field programmable gate array (FPGA), central processing unit (CPU), application specific integrated circuits (ASIC), digital signal processor (DSP) or graphics processing unit (GPU) hardware arranged homogenously or heterogeneously. The memory706may be but is not limited to a random access memory (RAM), read only memory (ROM), or other electronic, optical, magnetic or any other computer readable medium.

The detector testing system600may also include a target gas delivery hose752fluidly connected to the testing chamber610. The target gas tank750may be fluidly connected to the testing chamber610through a target gas delivery hose752. The target gas metering component760may be located within the target gas delivery hose752interposed between the testing chamber610and the target gas tank750. The target gas metering component760may be a metering valve, solenoid valve, stepper motor valve or similar component known to one of skill in the art. The target gas metering component760may adjust or meter how much of the target gas is delivered from the target gas tank750to the testing chamber610. In one example, the target gas metering performed by the target gas metering component760may be done with a controller that opens a solenoid valve for a specific time, which is correlated to a quantity of refrigerant. In another example, the target gas metering performed by the target gas metering component760may be done by opening a stepper motor valve, measuring the flow rate with a flow-meter, and correlating that the flow rate to a quantity of refrigerant.

The target gas delivery hose752is configured to deliver the target gas into the testing chamber610. The target gas tank750contains a known concentration of the target gas, such as, for example, 0%, 10%, 20%, 30%, 40%, 50%, 60%, 70%, 80%, 90%, 100%, or any concentration therebetween. In one embodiment, the target gas tank750may contain a known concentration of the target gas equal to about 100%. The detector testing system600includes target gas metering component760to adjust flow of the target gas from the target gas tank750into the testing chamber610.

The detector testing system600may also include a target gas return hose772fluidly connected to the testing chamber610. The target gas tank750may be fluidly connected to the testing chamber610through a target gas return hose772. A target gas reclaim component770may be located within the target gas return hose772interposed between the testing chamber610and the target gas tank750. The target gas reclaim component770may be a valve, a pump, a hermetic pump rated for flammable refrigerant, or any similar device known to one of skill in the art. The target gas reclaim component770may be configured to pump the target gas from the testing chamber610to the target gas tank750through the target gas return hose772once testing is completed. The pressure of the testing chamber610will be measured and pumped down to 0 psig.

The detector testing system600may also include a display device720configured to display response data of the HVAC/R system300. The response data may indicate whether the HVAC/R system300has performed (or is performing) an isolation and pump down procedure following the introduction of the target gas into the testing chamber610. The display device720may be controlled with a computing program, such as, for example, Vissim or MATLAB. The display device720may be a computer monitor or one or more lights with different meanings (e.g., red=test failed; green=test passed).

Referring now toFIG.5, with continued reference toFIG.4, a flow chart of a method800of testing the gas detector200for an HVAC/R system300is illustrated, in accordance with an embodiment of the present disclosure. The method800may indicate a pass or fail of a safety system test. In an embodiment, the method800is performed by the detector testing system600. At block804, the gas detector200is inserted through an orifice618in a detector testing system600and at least partially into a testing chamber610within the detector testing system600. The testing chamber610being configured to at least partially enclose the gas detector200within the testing chamber610. In an embodiment, the testing chamber610is configured to at least totally or completely enclose the gas detector200within the testing chamber610.

At block806, the testing chamber610is sealed off from external environments210external to the testing chamber610. The testing chamber610may be sealed off from external environments by sealing the cup mounting surface612against a mounting surface302of the HVAC/R system300while the gas detector200remains attached to the mounting surface302; and partially enclosing the gas detector200within the testing chamber610.

At block808, a target gas is provided into the testing chamber610from a target gas tank750containing a known concentration of the target gas. In an embodiment, the target gas is a refrigerant. In another embodiment, the target gas is a mildly flammable refrigerant. In another embodiment, the target gas is an A2 refrigerant, A2L refrigerant, or an A3 refrigerant. In another embodiment, the known concentration of the target gas within the target gas cartridge is a lower flammability limit of the target gas.

At block810, response data is received from the HVAC/R system300. The response data may indicate whether the HVAC/R system300has performed or is performing an isolation and pump down procedure following the introduction of the target gas into the testing chamber610. If the HVAC/R system300has performed (or is performing) an isolation and pump down procedure following the introduction of the target gas then the HVAC/R system300is considered to have passed a safety system test. If the HVAC/R system300has not performed (or is not performing) an isolation and pump down procedure following the introduction of the target gas then the HVAC/R system300is considered to have failed the safety system test.

The method800may further comprise that the target gas is transported from the testing chamber610to a target gas tank750. The target gas may be transported from the testing chamber610to a target gas tank750using the target gas reclaim component770through the target gas return hose772.

While the above description has described the flow processes ofFIG.5in a particular order, it should be appreciated that unless otherwise specifically required in the attached claims that the ordering of the steps may be varied.

As described above, embodiments can be in the form of processor-implemented processes and devices for practicing those processes, such as processor. Embodiments can also be in the form of computer program code (e.g., computer program product) containing instructions embodied in tangible media, such as floppy diskettes, CD ROMs, hard drives, or any other non-transitory computer readable medium, wherein, when the computer program code is loaded into and executed by a computer, the computer becomes a device for practicing the embodiments. Embodiments can also be in the form of computer program code, for example, whether stored in a storage medium, loaded into and/or executed by a computer, or transmitted over some transmission medium, loaded into and/or executed by a computer, or transmitted over some transmission medium, such as over electrical wiring or cabling, through fiber optics, or via electromagnetic radiation, wherein, when the computer program code is loaded into and executed by a computer, the computer becomes an device for practicing the exemplary embodiments. When implemented on a general-purpose microprocessor, the computer program code segments configure the microprocessor to create specific logic circuits.