Absorption refrigerator unit with temperature and level monitoring

Abstract

A control system for a refrigerator having an absorption cooling arrangement and a generator can include a temperature sensor associated with the generator and operable to sense a temperature of the cooling arrangement, a level sensor associated with the refrigerator and operable to sense a level condition of the cooling arrangement, and a heat source operably associated with at least the generator. A control circuit can include a processor and can be in communication with at least the temperature sensor, the level sensor and the heat source, and can be configured to determine a sensed temperature from the temperature sensor and a sensed level condition from the level sensor. The control circuit can be configured to turn off the heat source based on determining the sensed temperature is below a first predetermined threshold or based at least in part on determining the sensed level condition exceeds a second predetermined threshold.

1 . A control system for a refrigerator having an absorption cooling arrangement and a generator, comprising:
 a temperature sensor associated with the generator and operable to sense a temperature of the cooling arrangement proximate the generator;   a level sensor associated with the refrigerator and operable to sense a level condition of the cooling arrangement;   a heat source operably associated with at least the generator; and   a control circuit including a processor, the control circuit in communication with at least the temperature sensor, the level sensor and the heat source, the control circuit configured to determine a sensed temperature from the temperature sensor and a sensed level condition from the level sensor and configured to turn off the heat source based on determining the sensed temperature is below a first predetermined threshold or based at least in part on determining the sensed level condition exceeds a second predetermined threshold.   
     
     
         2 . The system of  claim 1 , further comprising a user interface associated with the refrigerator and operably associated with the control circuit, the control circuit configured to cause the user interface to display an error code if the sensed temperature is below the first predetermined threshold and a second error code if the sensed level condition exceeds the second predetermined threshold. 
     
     
         3 . The system of  claim 1 , wherein the control circuit further comprises a limit circuit operably associated with at least the processor and a relay, the control circuit configured to energize the relay providing an electrically open circuit in the limit circuit and cause the heat source to be turned off based on determining the sensed temperature is below the first predetermined threshold or based at least in part on determining the sensed level condition exceeds the second predetermined threshold. 
     
     
         4 . The system of  claim 3 , wherein the control circuit is configured to monitor the limit circuit to determine if an electrically open circuit condition exists in an absence of the relay being energized and, if so, cause the heat source to be turned off. 
     
     
         5 . The system of  claim 3 , wherein the control circuitry is configured to energize the relay after a first predetermined period of time has elapsed since the control circuitry received a signal to initiate cooling and the sensed temperature is below the first predetermined threshold. 
     
     
         6 . The system of  claim 3 , further comprising the control circuitry configured to energize the relay and cause the heat source to be turned off after: a first predetermined time has elapsed since the control circuitry received a signal to initiate cooling; the sensed level condition is determined to exceed the second predetermined threshold; and the sensed temperature is determined to exceed a third predetermined threshold. 
     
     
         7 . The system of  claim 6 , further comprising the control circuitry configured to determine whether the sensed temperature exceeds the third predetermined threshold before determining whether the sensed level condition exceeds the second predetermined threshold. 
     
     
         8 . The system of  claim 6 , further comprising the control circuitry configured to cause the heat source to be turned on after determining the sensed temperature is below a fourth predetermined threshold and after determining the sensed level condition is below the second predetermined threshold, wherein the fourth predetermined threshold is less than the third predetermined threshold. 
     
     
         9 . The system of  claim 1 , wherein the first predetermined threshold includes a temperature of approximately 250 degrees Fahrenheit. 
     
     
         10 . The system of  claim 1 , wherein the second predetermined threshold includes a range of approximately 5-6 degrees. 
     
     
         11 . The system of  claim 8 , wherein the third predetermined threshold includes a temperature of approximately 430 degrees Fahrenheit. 
     
     
         12 . The system of  claim 1 , further comprising the control circuitry configured to determine if the sensed temperature is outside of a predetermined normal operating range of the temperature sensor and, if so, cause the heat source to be turned off until at least the sensed temperature is within the predetermined normal operating range. 
     
     
         13 . The system of  claim 1 , wherein the heat source comprises a gas burner, an alternating current heater, a direct current heater, a solar heater, a fuel cell, or combinations thereof. 
     
     
         14 . The system of  claim 13 , wherein an energy source for the burner comprises a gas including butane or natural gas, or a liquid fuel including diesel or kerosene. 
     
     
         15 . A control system for a refrigerator having an absorption cooling arrangement and a generator, comprising:
 a temperature sensor associated with the generator and operable to sense a temperature of the cooling arrangement proximate the generator;   a level sensor associated with the refrigerator and operable to sense a level condition of the cooling arrangement;   a heat source operably associated with at least the generator;   a user interface associated with the refrigerator; and   a control circuit having a processor, the control circuit in communication with at least the temperature sensor, the level sensor, the heat source and the user interface, the control circuit configured to determine a sensed temperature from the temperature sensor and a sensed level condition from the level sensor and operable to turn off the heat source if the sensed temperature is determined to exceed a first predetermined threshold.   
     
     
         16 . The system of  claim 15 , further comprising the control circuit configured to determine if the sensed level condition is below a second predetermined threshold after determining that the sensed temperature exceeds the first predetermined threshold and, if so, cause the heat source to be turned off and display an error code on the user interface. 
     
     
         17 . The system of  claim 16 , wherein the control circuit further comprises a limit circuit operably associated with at least the processor and a relay, the control circuit configured to energize the relay providing an electrically open circuit in the limit circuit and cause the heat source to be turned off if the sensed temperature exceeds the first predetermined threshold and the sensed level condition is below the second predetermined threshold. 
     
     
         18 . The system of  claim 16 , further comprising the processor of the control circuitry configured to maintain the error code in a lock out mode thereby preventing the heat source from being turned on until the control circuitry receives a reset signal. 
     
     
         19 . The system of  claim 15 , further comprising the control circuitry configured to determine if the sensed level condition exceeds a second predetermined threshold after determining that the sensed temperature exceeds the first predetermined threshold and, if so, cause all heat source outputs to be turned off and display an error code on the user interface. 
     
     
         20 . The system of  claim 19 , further comprising the control circuit configured to cause the heat source to be turned on after determining the sensed temperature condition is below a third predetermined threshold and after determining the sensed level condition is below the second predetermined threshold, wherein the third predetermined threshold is less than the first predetermined threshold. 
     
     
         21 . The system of  claim 15 , wherein the heat source comprises a gas burner, an alternating current heater, a direct current heater, or combinations thereof. 
     
     
         22 . A method for controlling an absorption cooling arrangement of a refrigerator, comprising:
 determining if a predetermined period of time has elapsed since the cooling arrangement received a signal to initiate cooling of the refrigerator;   sensing a temperature proximate a generator associated with the cooling arrangement after determining the predetermined period of time has elapsed;   comparing the sensed temperature to a predetermined temperature condition; and   selectively turning off a heat source operably associated with the cooling arrangement based upon the comparison of the sensed temperature to the predetermined temperature condition.   
     
     
         23 . The method of  claim 22 , wherein comparing the sensed temperature includes determining if the sensed temperature is outside of a normal operating range of temperature sensor used to sense the temperature; and
 wherein selectively turning off the heat source occurs if the sensed temperature is determined to be outside of the normal operating range.   
     
     
         24 . The method of  claim 22 , wherein comparing the sensed temperature includes determining if the sensed temperature is below a predetermined threshold; and
 wherein selectively turning off a heat source occurs if the sensed temperature is determined to be below the predetermined threshold.   
     
     
         25 . The method of  claim 22 , wherein comparing the sensed temperature includes determining if the sensed temperature is greater than a first predetermined threshold and, if so, sensing a level condition of the cooling arrangement and determining if the level condition exceeds a second predetermined threshold. 
     
     
         26 . The method of  claim 25 , further comprising:
 turning off the heat source upon determining the level condition does not exceed the second predetermined threshold;   providing an error code to a user interface indicative of the sensed temperature being greater than the first predetermined threshold; and   activating a lock-out mode where the heat source remains turned off until the error code is reset.   
     
     
         27 . The method of  claim 25 , further comprising:
 turning off the heat source upon determining the level condition exceeds the second predetermined threshold;   providing an error code to a user interface indicative of the sensed temperature and the sensed level condition of the cooling arrangement being greater than the respective first and second predetermined thresholds;   monitoring the temperature proximate the generator and the level condition of the cooling arrangement; and   turning on the heat source upon determining the sensed temperature and the sensed level condition are below the respective first and second predetermined thresholds.