FAULT TOLERANT APPLIANCE

• US 20120031985A1
• Filed: 08/09/2010
• Published: 02/09/2012
• Est. Priority Date: 08/09/2010
• Status: Abandoned Application

• Current Assignee: General Electric Company
• Original Assignee: General Electric Company
• Inventors: Nold, Craig, Do, Terry Lien
• Application Number:
  US12/852,825
• Publication Number:
  US 20120031985A1
• Time in Patent Office: Days
• US Class Current: 236/46.A
• CPC Class Codes: F24F 11/30 for purposes related to the operation of the system, e.g. for safety or monitoring
• CPC Class Codes: F24F 11/32 Responding to malfunctions or emergencies
• CPC Class Codes: F24F 11/38 Failure diagnosis
• CPC Class Codes: F24F 11/52 Indication arrangements, e.g. displays
• CPC Class Codes: F24F 11/66 Sleep mode
• CPC Class Codes: F24F 2110/00 Control inputs relating to air properties
• CPC Class Codes: F25D 21/006 with electronic control circuits
• CPC Class Codes: F25D 21/008 by timer
• CPC Class Codes: F25D 2600/02 Timing
• CPC Class Codes: F25D 2700/10 Sensors measuring the temperature of the evaporator
• CPC Class Codes: F25D 2700/14 Sensors measuring the temperature outside the refrigerator or freezer
• CPC Class Codes: F25D 29/006 Safety devices
• CPC Class Codes: G05D 23/1928 sensing the temperature of one space
• CPC Class Codes: G05D 23/24 the sensing element having a resistance varying with temperature, e.g. a thermistor

Abstract

A method for controlling an appliance includes detecting a fault state of the appliance, determining that the fault state is associated with a monitoring sensor of the appliance, and changing an operational mode of a system of the appliance associated with the monitoring sensor to a time-based operational mode.

Claims

1. A method for controlling an appliance, comprising:

detecting a fault state of the appliance

determining that the fault state is associated with a monitoring sensor of the appliance; and

changing a sensor-based operational mode of a system of the appliance associated with the monitoring sensor to a time-based operational mode.

2. The method of claim 1, wherein the system is an air conditioning system and the monitoring sensor comprises an ambient air temperature detector and an evaporator thermistor.

3. The method of claim 2, further comprising, when the faith state is associated with the evaporator thermistor, changing a temperature-based defrost cycle to a time-based defrost cycle.

4. The method of claim 2, further comprising, when the fault state is associated with both the ambient air temperature detector and the evaporator thermistor, changing a cooling cycle of the air conditioning system from a temperature-based cooling cycle to a time-based cooling cycle, and, changing a temperature-based defrost cycle to a time-based defrost cycle.

5. The method of claim 2, further comprising, when the fault state is associated with the ambient air temperature detector, changing a cooling cycle of the air conditioning system from a temperature-based cooling cycle to a time-based cooling cycle.

6. The method of claim 5, further comprising cycling an operation of a compressor associated with the air conditioning system between a pre-determined on-state and a pre-determined off-state.

7. The method of claim 5, further comprising:

determining a relationship between a last known temperature set-point and a last known room temperature; and

cycling an operation of the air conditioning system between a pre-determined on-state and a pre-determined off-state, where a time period for the pre-determined on-state and a time-period for the pre-determined off state is based on the relationship between the last known temperature set-point and the last known room temperature.

8. The method of claim 1, wherein the appliance is an air-conditioning system, a refrigerator unit, a heat pump, a dehumidifier unit or a freezer unit.

9. The method of claim 1, wherein the appliance is a refrigerant based compressor cooling system.

10. The method of claim 1, further comprising determining that the fault state corresponds to a failure mode that is critical to an operation of the appliance and enabling a power off state of the appliance.

11. The method of claim 2, further comprising when the fault state is associated with an ambient air temperature detector, changing a heating cycle of the air conditioning system from a temperature-based heating cycle to a time-based heating cycle.

12. An appliance comprising:

an air conditioning system;

a controller for controlling an operational cycle of the air conditioning system;

a sensor coupled to the air conditioning system for providing operational data for the air conditioning system to the controller; and

a fault detector coupled to the air conditioning system, the fault detector configured to detect a fault state related to the sensor.

wherein the controller is configured to change a sensor-based operational cycle of the air conditioning system to a time-based operational cycle upon detection of the fault state.

13. The appliance of claim 12, wherein the sensor is an ambient air temperature detector or an evaporator thermistor.

14. The appliance of claim 13, wherein the controller is further configured to detect a fault related to the evaporator thermistor and change a temperature-based defrost cycle to a time-based defrost cycle.

15. The appliance of claim 13, wherein the controller is further configured to detect a fault related to each of the ambient air temperature detector and the evaporator thermistor and to change a cycle of the air conditioning system from a temperature-based cooling cycle to a time-based cooling cycle, and change a temperature-based defrost cycle to a time-based defrost cycle.

16. The appliance of claim 13, wherein the controller is further configured to detect a fault related to the ambient air temperature detector and to change a compressor run cycle of the air conditioning system from a temperature-based run cycle to a time-based run cycle.

17. The appliance of claim 16, wherein the controller is further configured to determine a relationship between a last known temperature set-point and a last known room temperature, and to cycle an operation of the air conditioning system between an on-state and an off-state, where a time period for the on-state and a time-period for the off state is based on the relationship between the last known temperature set-point and the last known room temperature.

18. The appliance of claim 12, wherein the appliance is an air-conditioning system, a refrigeration unit, a dehumidifier, a heat pump or a freezer.

19. The appliance of claim 12, wherein the appliance is a refrigerant-based compressor cooling system.

20. The appliance of claim 12, wherein the controller is further configured to determine that the fault state corresponds to a failure mode that is critical to an operation of the appliance and enable a power off state of the appliance.

21. The appliance of claim 12, further comprising a compressor associated with the air conditioning system and configured to cycle between an on-state for a pre-determined time period and an off-state for a pre-determined time period.