Temperature evaluations using water temperature and humidity sensor in a washing machine

Abstract

A laundry appliance includes a tub, a drum rotatably mounted within the tub and defining a chamber configured for receiving a load of clothes, a water temperature sensor in the tub, and a humidity sensor having an air temperature sensor in an exhaust in fluid communication with the chamber. A controller is configured to take a series of readings from the water temperature sensor and the air temperature sensor, to determine a difference or average of the temperature changes in those sensors, and to compare the rate of temperature change over time. Where the controller determines that the rate of change between the water temperature sensor and the air temperature sensor is inconsistent, the controller provides a notification to the user that one or both of the temperature sensors is in error and requires servicing.

What is claimed is: 
     
         1 . A laundry appliance comprising:
 a cabinet;   a tub within the cabinet;   a drum rotatably mounted within the tub and defining a chamber;   an exhaust in fluid communication with the chamber;   a first temperature sensor;   a second temperature sensor;   a controller operably coupled to the first temperature sensor and the second temperature sensor, the controller being configured to:
 execute a wash cycle; 
 receive a first temperature from the first temperature sensor; 
 receive a first temperature from the second temperature sensor; 
 receive a second temperature from the first temperature sensor; 
 receive a second temperature from the second temperature sensor; 
 determine the temperature change of the first temperature sensor and the second temperature sensor based at least in part on the first temperature and the second temperature of the first temperature sensor and the second temperature sensor; 
 compare the temperature change of the first temperature sensor to the temperature change of the second temperature sensor; 
 determine if either of the first temperature sensor or the second temperature sensor are malfunctioning based on the comparison. 
   
     
     
         2 . The laundry appliance of  claim 1 , wherein the controller is further configured to provide a notification to the user if it is determined that either of the first temperature sensor or the second temperature sensor are malfunctioning. 
     
     
         3 . The laundry appliance of  claim 1 , wherein the first temperature sensor is disposed in the tub. 
     
     
         4 . The laundry appliance of  claim 3 , wherein the first temperature sensor measures a water temperature. 
     
     
         5 . The laundry appliance of  claim 1 , wherein the second temperature sensor is disposed in the exhaust. 
     
     
         6 . The laundry appliance of  claim 5 , wherein the second temperature sensor measures an air temperature. 
     
     
         7 . The laundry appliance of  claim 6 , wherein the second temperature sensor is part of a humidity sensor. 
     
     
         8 . The laundry appliance of  claim 1 , wherein the temperature change of the first temperature sensor and the second temperature sensor is an average change of temperature of the first temperature sensor and the second temperature sensor based on a plurality of temperature readings of the first temperature sensor and the second temperature sensor. 
     
     
         9 . The laundry appliance of  claim 8 , wherein comparing the temperature change of the first temperature sensor and the second temperature sensor further includes comparing the average change of temperature of the first temperature sensor and the second temperature sensor. 
     
     
         10 . The laundry appliance of  claim 1 , wherein determining if either of the first temperature sensor or the second temperature sensor are malfunctioning further includes determining whether the temperature change of the first temperature sensor is consistent with the temperature change of the second temperature sensor. 
     
     
         11 . The laundry appliance of  claim 10 , wherein the temperature change of the first temperature sensor is consistent with the temperature change of the second temperature sensor if the temperature change of the first temperature sensor and the second temperature sensor both increase, decrease, or remain the same. 
     
     
         12 . The laundry appliance of  claim 10 , wherein the temperature change of the first temperature sensor is not consistent with the temperature change of the second temperature sensor if the temperature change of one of the first temperature sensor or the second temperature sensor has a temperature change and the other does not. 
     
     
         13 . The laundry appliance of  claim 1 , wherein the wash cycle continues if it is determined that the first temperature sensor and the second temperature sensor are not malfunctioning. 
     
     
         14 . The laundry appliance of  claim 13 , wherein the controller is further configured to repeat the steps of receiving the first temperature and the second temperature from the first temperature sensor and the second temperature sensor, determining the temperature change of the first temperature sensor and the second temperature sensor, comparing the temperature change of the first temperature sensor and the second temperature sensor, and determining if either of the first temperature sensor or the second temperature sensor is malfunctioning throughout the wash cycle. 
     
     
         15 . A method for monitoring for temperature sensor malfunctions in a laundry appliance having a cabinet, a tub within the cabinet, a drum rotatably mounted within the tub and defining a chamber, an exhaust in fluid communication with the chamber, a first temperature sensor in the tub for measuring water temperature, and a second temperature sensor in a humidity sensor disposed in the exhaust for measuring air temperature, the method comprising:
 executing a wash cycle;   receiving a first temperature from the first temperature sensor;   receiving a first temperature from the second temperature sensor;   receiving a second temperature from the first temperature sensor;   receiving a second temperature from the second temperature sensor;   determining the temperature change of the first temperature sensor and the second temperature sensor based at least in part on the first temperature and the second temperature of the first temperature sensor and the second temperature sensor;   comparing the temperature change of the first temperature sensor to the temperature change of the second temperature sensor;   determining if either of the first temperature sensor or the second temperature sensor are malfunctioning based on the comparison.   
     
     
         16 . The method of  claim 15 , wherein the method further comprises providing a notification to the user if it is determined that either of the first temperature sensor or the second temperature sensor are malfunctioning. 
     
     
         17 . The method of  claim 15 , wherein the temperature change of the first temperature sensor and the second temperature sensor is an average change of temperature of the first temperature sensor and the second temperature sensor based on a plurality of temperature readings of the first temperature sensor and the second temperature sensor. 
     
     
         18 . The method of  claim 17 , wherein comparing the temperature change of the first temperature sensor and the second temperature sensor further includes comparing the average change of temperature of the first temperature sensor and the second temperature sensor. 
     
     
         19 . The method of  claim 15 , wherein determining if either of the first temperature sensor or the second temperature sensor are malfunctioning further includes determining the temperature change of the first temperature sensor is consistent with the temperature change of the second temperature sensor. 
     
     
         20 . The method of  claim 19 , wherein the temperature change of the first temperature sensor is not consistent with the temperature change of the second temperature sensor if the temperature change of one of the first temperature sensor or the second temperature sensor has a temperature change, and the other does not.