# US 11,906,223 B2 · Systems and methods for determining a fault of an air system for heating, ventilation and/or cooling

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- Number: US 11,906,223 B2
- Document ID: US11906223B2
- Status: Granted
- Kind: B2
- Application number: 17/192,078
- Filed: 2021-03-04
- Published: 2022-09-08
- Granted: 2024-02-20
- Earliest claimed: 2021-03-04
- Assignees: Rheem Manufacturing Company
- Applicants: Rheem Manufacturing Company
- Inventors: Sivakumar Gopalnarayanan; Ammar K. Sakarwala
- Web page: https://patentgrep.com/patent/US11906223B2

## CPC

- F25B 49/005: {of safety devices (F25B49/02 and F25B49/04 take precedence)}
- F25B 49/02: for compression type machines, plants or systems
- F24F 11/38: Failure diagnosis
- F25B 13/00: Compression machines, plants or systems, with reversible cycle (defrosting cycles F25B47/02)
- F24F 11/36: to leakage of heat-exchange fluid
- F25B 2500/04: Clogging
- F25B 2500/12: Sound
- F25B 2500/13: Vibrations
- F25B 2500/222: Detecting refrigerant leaks
- F25B 2600/0253: with variable speed
- F25B: REFRIGERATION MACHINES, PLANTS OR SYSTEMS; COMBINED HEATING AND REFRIGERATION SYSTEMS; HEAT PUMP SYSTEMS
- F24F: AIR-CONDITIONING; AIR-HUMIDIFICATION; VENTILATION; USE OF AIR CURRENTS FOR SCREENING (removing dirt or fumes from areas where they are produced B08B15/00; vertical ducts for carrying away waste gases from buildings E04F17/02; tops for chimneys or ventilating shafts, terminals for flues F23L17/02)

## Abstract

The disclosed technology includes a method for identifying and determining a fault or a potential fault in an air system having an outdoor unit and an indoor unit in fluid communication via a refrigerant circuit. The method can include receiving, from a sensor, vibration data indicative of one or more sounds or vibrations detected by at least a portion of the refrigerant circuit. The method can include identifying, based at least in part on the vibration data and stored baseline vibration data, an abnormality in the vibration data. The abnormality can be indicated by vibration data indicative of a frequency that is outside a range of acceptable frequencies. The method can include analyzing the identified abnormality according to a predetermined set of evaluation factors to determine the fault or the potential fault.

## Claims

### Claim 1

A heating, ventilation, and air-conditioning (HVAC) system comprising:
a first heat exchanger in fluid communication with a refrigerant circuit;
a second heat exchanger in fluid communication with the refrigerant circuit;
a compressor in fluid communication with the refrigerant circuit;
a sensor located in or on a housing comprising the compressor, wherein the sensor is configured to detect vibration data, the vibration data being indicative of one or more sounds or vibrations detected via at least a portion of the refrigerant circuit;
a processor; and
a non-transitory computer-readable medium that stores instructions that, when executed by the processor, cause the system to:
receive the vibration data;
identify, based at least in part on the vibration data and stored baseline vibration data, an abnormality in the vibration data, wherein the abnormality is indicated by vibration data indicative of a frequency that is outside of a predetermined range of acceptable frequencies;
determine a difference between the frequency of the identified abnormality and the predetermined range of acceptable frequencies;
if the difference is greater than a first threshold, determine the fault will occur in an estimated amount of time; and
if the difference is greater than a second threshold, the second threshold being greater than the first threshold, determine the fault is occurring or has occurred.

### Claim 2 (depends on 1)

The HVAC system of claim 1, wherein the sensor is a high-frequency sensor.

### Claim 3 (depends on 1)

The HVAC system of claim 1, wherein the sensor includes an accelerometer configured to detect vibrations associated with the system.

### Claim 4 (depends on 1)

The HVAC system of claim 1, wherein the sensor is disposed on the compressor.

### Claim 5 (depends on 1)

The HVAC system of claim 1, wherein the sensor is disposed on a conduit of the refrigerant circuit at a location that is between the compressor and the second heat exchanger.

### Claim 6 (depends on 1)

The HVAC system of claim 1, wherein the fault is at least one or more of: (i) at least partial blockage of air flow in the first heat exchanger; (ii) at least partial blockage of air flow in the second heat exchanger; (iii) a leak of refrigerant flowing through the refrigerant circuit; (iv) at least a partial failure of a motor of a fan configured to move air through the housing; or (v) at least a partial failure of a capacitor disposed within the housing.

### Claim 7 (depends on 1)

The HVAC system of claim 1, wherein the first heat exchanger and the second heat exchanger are located in a single unit.

### Claim 8 (depends on 1)

The HVAC system of claim 1, wherein the predetermined set of evaluation factors includes a first band of frequencies and a second band of frequencies, the first band of frequencies being associated with a first fault and a second band of frequencies being associated with a second fault.

### Claim 9 (depends on 1)

The HVAC system of claim 1, wherein the processor is further configured to output display data for display on a display device, the display data being based at least in part on the determined fault.

### Claim 10

A method of determining a fault in a system comprising an outdoor unit and an indoor unit in fluid communication via a refrigerant circuit, the method comprising:
receiving, from a sensor, vibration data, the vibration data being indicative of one or more sounds or vibrations detected via a portion of the refrigerant circuit;
identifying, based at least in part on the vibration data and stored baseline vibration data, an abnormality in the vibration data, wherein the abnormality is indicated by vibration data indicative of a frequency that is outside of a predetermined range of acceptable frequencies;
determining a difference between the frequency of the identified abnormality and the predetermined range of acceptable frequencies;
if the difference is greater than a first threshold, determining the fault will occur in an estimated amount of time; and
if the difference is greater than a second threshold, the second threshold being greater than the first threshold, determining the fault is occurring or has occurred.

### Claim 11 (depends on 10)

The method of claim 10, further comprising recording, by the sensor, the vibration data over a predetermined time period.

### Claim 12 (depends on 10)

The method of claim 10, further comprising, transmitting, by the sensor, the vibration data a predetermined number of times during a predetermined time period.

### Claim 13 (depends on 10)

The method of claim 10, wherein the sensor is located in or on the outdoor unit.

### Claim 14 (depends on 10)

The method of claim 10, wherein the predetermined set of evaluation factors includes a first band of frequencies and a second band of frequencies, the first band of frequencies associated with a first fault and a second band of frequencies associated with a second fault that is different from the first fault.

### Claim 15 (depends on 10)

The method of claim 10, wherein the stored baseline vibration data is indicative of no faults in the system, and identifying, based at least in part on the vibration data and stored baseline vibration data, the abnormality in the vibration data comprises determining the vibration data is a predetermined amount different than the stored baseline vibration data.

### Claim 16 (depends on 10)

The method of claim 10, further comprising outputting display data for display on a display device, the display data being based at least in part on the determined fault.

### Claim 17 (depends on 10)

The method of claim 10, wherein the fault is one or more of: (i) at least partial blockage of air flow in an indoor heat exchanger of the indoor unit; (ii) at least partial blockage of air flow in an outdoor heat exchanger of the outdoor unit; (iii) a leak of refrigerant flowing through the refrigerant circuit; (iv) at least a partial failure of a motor of a fan disposed within the indoor unit or outdoor unit; or (v) at least a partial failure of a capacitor disposed within the outdoor unit.