System and method for monitoring charge level of hvac system

Patent metadata

Field	Value
Publication number	US-2021140661-A1
Application number	US-201916681576-A
Country	US
Kind code	A1
Filing date	Nov 12, 2019
Priority date	Nov 12, 2019
Publication date	May 13, 2021
Grant date	—

Abstract

A heating, ventilation, and/or air conditioning (HVAC) system includes a sensor configured to detect an operating parameter of the HVAC system, a processor, and a memory having instructions executable by the processor to cause the processor, during a normal operation mode of the HVAC system, to iteratively receive feedback from the sensor indicative of a value of the operating parameter, compare the value with reference data, and determine a refrigerant charge level of the HVAC system based on the value and the reference data.

First claim

1 . A heating, ventilation, and/or air conditioning (HVAC) system, comprising:
a sensor configured to detect an operating parameter of the HVAC system; a processor; and a memory including instructions executable by the processor to cause the processor, during a normal operation mode of the HVAC system, to iteratively:
receive feedback from the sensor indicative of a value of the operating parameter;
compare the value with reference data; and
determine a refrigerant charge level of the HVAC system based on the value and the reference data.

2 . The HVAC system of claim 1 , wherein the operating parameter includes a discharge pressure of a compressor of the HVAC system, a discharge temperature of the compressor, a suction pressure of the compressor, a suction temperature of the compressor, a liquid pressure of refrigerant circulating the HVAC system, a liquid temperature of refrigerant circulating the HVAC system, an evaporating pressure of the refrigerant in an evaporator of the HVAC system, an evaporating temperature of the refrigerant in the evaporator, an evaporating pressure of the refrigerant in a condenser of the HVAC system, an evaporating temperature of the refrigerant in the condenser, a power consumption of the HVAC system, a rotation of a motor of the compressor, an operation of a fan of the HVAC system, an air flow rate through the HVAC system, a humidity of a space conditioned by the HVAC system, a temperature of the space conditioned by the HVAC system, an ambient temperature, or any combination thereof.

3 . The HVAC system of claim 1 , wherein the reference data is a reference data point, and the instructions cause the processor to update the reference data point to an updated reference data point based on comparing the value of the operating parameter with the reference data point.

4 . The HVAC system of claim 1 , wherein the sensor is a component of an HVAC unit, and the memory and the processor are components of a controller of the HVAC unit.

5 . The HVAC system of claim 1 , wherein the sensor is a component of an HVAC unit, and the memory and the processor are components of a cloud-based system.

6 . The HVAC system of claim 5 , comprising a controller of the HVAC unit, wherein the controller is configured to transmit the feedback from the sensor to the processor.

7 . The HVAC system of claim 6 , wherein the controller is a thermostat.

8 . The HVAC system of claim 1 , wherein the instructions are executable by the processor to cause the processor to output a notification in response to a determination that the value of the operating parameter deviates from the reference data, and the notification is indicative that the refrigerant charge level of the HVAC system is different than an expected refrigerant charge level of the HVAC system.

9 . The HVAC system of claim 1 , wherein the instructions are configured to be executed by the processor upon startup of the HVAC system in the normal operation mode, once per minute during the normal operation mode, or both.

10 . A non-transitory computer readable storage medium for a heating, ventilation, and/or air conditioning (HVAC) system comprising instructions that, when executed by a processor, are configured to cause the processor, during a normal operation mode of the HVAC system, to:
receive an input indicative of an operating parameter value of the HVAC system from a sensor of the HVAC system; correlate the operating parameter value to reference data determined in testing of the HVAC system; and determine a refrigerant charge level of the HVAC system based on correlation of the operating parameter value and the reference data.

11 . The non-transitory computer readable storage medium of claim 10 , wherein the reference data is a reference data point, and the instructions, when executed by the processor, are configured to cause the processor to receive the input indicative of the operating parameter value, compare the operating parameter value to the reference data point, and determine the refrigerant charge level of the HVAC system for a plurality of iterations.

12 . The non-transitory computer readable storage medium of claim 11 , wherein the instructions, when executed by the processor, are configured to update the reference data point to be an updated reference data point based on the comparison of the operating parameter value to the reference data point in the plurality of iterations.

13 . The non-transitory computer readable storage medium of claim 12 , wherein the updated reference data point is within a tolerance range determined in testing of the HVAC system.

14 . The non-transitory computer readable storage medium of claim 12 , wherein the operating parameter value indicated by the input received in the plurality of iterations is a steady state value, and a value of the updated reference data point is equal to the steady state value.

15 . The non-transitory computer readable storage medium of claim 10 , wherein the non-transitory computer readable storage medium is a component of an onboard controller of the HVAC system.

16 . The non-transitory computer readable storage medium of claim 10 , wherein the non-transitory computer readable storage medium is a component of a cloud-based system.

17 . The non-transitory computer readable storage medium of claim 10 , wherein the instructions, when executed by the processor, are configured to:
determine that the refrigerant charge level of the HVAC system is an expected refrigerant charge level in response to a determination that the operating parameter value is substantially the same as the reference data; and determine that the refrigerant charge level of the HVAC system deviates from the expected refrigerant charge level in response to a determination that the operating parameter value is substantially different than the reference data.

18 . The non-transitory computer readable storage medium of claim 17 , wherein the instructions, when executed by the processor, are configured to output an indication in response to a determination that the refrigerant charge level of the HVAC system deviates from the expected refrigerant charge level.

19 . A heating, ventilation, and/or air conditioning (HVAC) system, comprising:
a plurality of sensors, wherein each sensor of the plurality of sensors is configured to detect a respective operating parameter of a plurality of operating parameters of the HVAC system; and a controller configured to, during a normal operation mode of the HVAC system, iteratively:
receive feedback from the plurality of sensors, wherein the feedback includes a respective value associated with each operating parameter of the plurality of operating parameters of the HVAC system;
compare each value with respective reference data; and
determine a current refrigerant charge level of the HVAC system based on comparison of each value with the respective reference data.

20 . The HVAC system of claim 19 , wherein the controller is configured to:
determine that feedback from a sensor of the plurality of sensors is indicative of a first deviation of a value of a particular operating parameter from a corresponding reference data point; determine whether the first deviation is caused by a second deviation of the current refrigerant charge level from an expected refrigerant charge level based on feedback from an additional sensor of the plurality of sensors; and determine the current refrigerant charge level of the HVAC system based on the first deviation of the value of

Assignees

• Johnson Controls Tech Co

Inventors

• Mccune Tyler P
• Hern Shawn A
• Noor Aneek M
• Kaiser Cody J
• Carlton Drew H

Classifications

• F24F2140/12

  Heat-exchange fluid pressure · CPC title

• F24F2140/20

  Heat-exchange fluid temperature · CPC title

• F24F11/32 Primary

  Responding to malfunctions or emergencies · CPC title

• F24F11/63

  Electronic processing · CPC title