Heat pump system with refrigerant charge diagnostics

• US 10,060,636 B2
• Filed: 01/28/2015
• Issued: 08/28/2018
• Est. Priority Date: 04/05/2013
• Status: Active Grant

• Current Assignee: Copeland Corporation LLC (Emerson Electric Company)
• Original Assignee: Emerson Climate Technologies Incorporated (Emerson Electric Company)
• Inventors: Alsaleem, Fadi M., Hemmelgarn, Gregg M.
• Primary Examiner(s): Teitelbaum, David
• Assistant Examiner(s): Alvare, Paul
• Application Number:
  US14/607,782
• Publication Number:
  US 20150135748A1
• Time in Patent Office: 1,308 Days
• Field of Search: 165 111, 165288-293, 62126, 62129
• CPC Class Codes: F24D 19/1087 system using a heat pump
• CPC Class Codes: F24D 2220/042 Temperature sensors
• CPC Class Codes: F24H 15/104 Inspection; Diagnosis; Trial operation
• CPC Class Codes: F24H 15/204 Temperature of the air before heating
• CPC Class Codes: F24H 15/208 Temperature of the air after heating
• CPC Class Codes: F24H 15/232 at the condenser
• CPC Class Codes: F24H 15/395 Information to users, e.g. alarms
• CPC Class Codes: F24H 15/45 remotely accessible
• CPC Class Codes: F25B 13/00 Compression machines, plants or systems, with reversible cycle defrosting cycles F25B47/02
• CPC Class Codes: F25B 2500/22 Preventing, detecting or repairing leaks of refrigeration fluids
• CPC Class Codes: F25B 2500/23 High amount of refrigerant in the system
• CPC Class Codes: F25B 2500/24 Low amount of refrigerant in the system
• CPC Class Codes: F25B 2700/2106 of fresh outdoor air
• CPC Class Codes: F25B 2700/21161 of the fluid heated by the condenser
• CPC Class Codes: F25B 2700/21163 of the refrigerant at the outlet of the condenser
• CPC Class Codes: F25B 2700/21172 at the inlet
• CPC Class Codes: F25B 2700/21173 at the outlet
• CPC Class Codes: F25B 49/00 Arrangement or mounting of control or safety devices
• CPC Class Codes: F25B 49/005 of safety devices F25B49/02 and F25B49/04 take precedence
• CPC Class Codes: H05K 999/99 dummy group

Abstract

A heat-pump circuit may include an indoor heat exchanger, an outdoor heat exchanger, a compressor adapted to circulate a working fluid between the indoor and outdoor heat exchangers, and an expansion device disposed between the indoor and outdoor heat exchangers. A monitor for the heat-pump system may include a return-air temperature sensor, a supply-air temperature sensor, and a processor. The return-air temperature sensor may be adapted to measure a first air temperature of air upstream of the indoor heat exchanger. The supply-air temperature sensor may be adapted to measure a second air temperature of air downstream of the indoor heat exchanger. The processor may be in communication with the return-air temperature sensor and the supply-air temperature sensor. The processor may be programmed to determine a working-fluid-charge condition of the heat-pump system based on the first and second air temperatures.

Claims

1. A monitor for a heat-pump system having indoor and outdoor heat exchangers, a compressor circulating a working fluid between the indoor and outdoor heat exchangers, and an expansion device between the indoor and outdoor heat exchangers, the monitor comprising:

a return-air temperature sensor adapted to measure a first air temperature of air upstream of the indoor heat exchanger;

a supply-air temperature sensor adapted to measure a second air temperature of air downstream of the indoor heat exchanger;

a working-fluid temperature sensor disposed between the expansion device and the indoor heat exchanger and adapted to measure a working-fluid temperature of working fluid flowing between the indoor heat exchanger and the expansion device when the heat-pump system is operating in a heating mode; and

a processor in communication with the return-air temperature sensor, the supply-air temperature sensor and the working-fluid temperature sensor, the processor configured to determine a first difference between the second air temperature and the working-fluid temperature and a second difference between the second air temperature and the first air temperature, the processor configured to determine a working-fluid-charge condition of the heat-pump system based on a first comparison of the first difference with a first predetermined value and a second comparison of the second difference with a second predetermined value.

2. The monitor of claim 1, wherein the processor is in communication with a notification device configured to generate an alert indicating the working-fluid-charge condition.

3. The monitor of claim 1, wherein the processor is in communication with a notification device configured to generate a first alert indicating that a fault condition of the heat-pump system is related to the working-fluid-charge condition and a second alert indicating that the fault condition of the heat-pump system is unrelated to an amount of working fluid in the heat-pump system.

4. The monitor of claim 3, wherein the processor is a cloud-based processor and the notification device includes a mobile, wireless computing device.

5. The monitor of claim 1, wherein the processor is a cloud-based processor disposed remotely from the compressor, the return-air temperature sensor and the supply-air temperature sensor.

6. The monitor of claim 1, wherein the processor is configured to determine a third difference between the working-fluid temperature and the first air-temperature, and wherein the processor is configured to determine a working-fluid-charge condition of the heat-pump system based on the first comparison of the first difference with the first predetermined value and a third comparison of the third difference with a third predetermined value.

7. The monitor of claim 6, wherein the processor is configured to determine the working-fluid-charge condition of the heat-pump system based on the first comparison and the second comparison if the first difference is higher than the first predetermined value, and wherein the processor determines the working-fluid-charge condition of the heat-pump system based on the first comparison and the third comparison if the first difference is lower than the first predetermined value.

8. The monitor of claim 7, wherein the processor is in communication with a notification device configured to generate a first alert indicating that a fault condition of the heat-pump system is related to a working fluid overcharge condition if the second difference is higher than the second predetermined value and a second alert indicating that the fault condition of the heat-pump system is unrelated to an amount of working fluid in the heat-pump system if the second difference is lower than the second predetermined value.

9. The monitor of claim 8, wherein the notification device is configured to generate a third alert indicating that the fault condition of the heat-pump system is related to a working fluid undercharge condition if the third difference is lower than the third predetermined value and a fourth alert indicating that the fault condition of the heat-pump system is unrelated to an amount of working fluid in the heat-pump system if the third difference is higher than the third predetermined value.

10. A heat-pump system having a processor in communication with a return-air temperature sensor adapted to measure a first air temperature of air upstream of an indoor heat exchanger, a supply-air temperature sensor adapted to measure a second air temperature of air downstream of the indoor heat exchanger and a working-fluid temperature sensor, a compressor circulating a working fluid between the indoor heat exchanger and an outdoor heat exchanger, and an expansion device between the indoor and outdoor heat exchangers, the working-fluid temperature sensor disposed between the expansion device and the indoor heat exchanger and adapted to measure a working-fluid temperature of working fluid flowing between the indoor heat exchanger and the expansion device when the heat-pump system is operating in a heating mode, the processor configured to determine a first difference between the second air temperature and the working-fluid temperature and a second difference between the second air temperature and the first air temperature, the processor configured to determine a working-fluid-charge condition of the heat-pump system based on a first comparison of the first difference with a first predetermined value and a second comparison of the second difference with a second predetermined value.

11. The heat-pump system of claim 10, wherein the processor is in communication with a notification device configured to generate an alert indicating the working-fluid-charge condition.

12. The heat-pump system of claim 10, wherein the processor is a cloud-based processor disposed remotely from the compressor, the return-air temperature sensor and the supply-air temperature sensor.

13. The heat-pump system of claim 10, wherein the processor is in communication with a notification device configured to generate a first alert indicating that a fault condition of the heat-pump system is related to the working-fluid-charge condition and a second alert indicating that the fault condition of the heat-pump system is unrelated to an amount of working fluid in the heat-pump system.

14. The heat-pump system of claim 13, wherein the processor is a cloud-based processor and the notification device includes a mobile, wireless computing device.

15. The heat-pump system of claim 10, wherein the processor is configured to determine the working-fluid-charge condition of the heat-pump system based on the first comparison and the second comparison if the first difference is higher than the first predetermined value.

16. The heat-pump system of claim 15, wherein the processor is in communication with a notification device configured to generate a first alert indicating that a fault condition of the heat-pump system is related to a working fluid overcharge condition if the second difference is higher than the second predetermined value and a second alert indicating that the fault condition of the heat-pump system is unrelated to an amount of working fluid in the heat-pump system if the second difference is lower than the second predetermined value.

17. The heat-pump system of claim 16, wherein the processor is configured to determine the working-fluid-charge condition of the heat-pump system based on the first comparison and a third comparison if the first difference is lower than the first predetermined value, wherein the third comparison is a comparison between a third predetermined value and a third difference between the working-fluid temperature and the first air temperature.