Dishwasher appliance having a pressure sensor for flood detection

Abstract

A dishwasher appliance that includes features for prevention and detection of flood events or tub overfills without sacrificing performance or efficiency of the dishwasher appliance is provided. Moreover, methods for detecting and preventing such flood events are also provided.

What is claimed is: 
     
         1 . A method for detecting a flood event in a dishwasher appliance, the dishwasher appliance comprising a pressure sensor, a drain pump, and a circulation pump, the method comprising:
 determining whether the circulation pump is activated;   determining whether a pressure sensor output of the pressure sensor is greater than or equal to a first pressure threshold for a predetermined time if the circulation pump is not activated, or, determining whether the pressure sensor output of the pressure sensor is greater than or equal to a second pressure threshold for a predetermined time if the circulation pump is activated; and   activating the drain pump if the pressure sensor output is greater than or equal to either the first pressure threshold for the predetermined time or the second pressure threshold for the predetermined time.   
     
     
         2 . The method of  claim 1 , further comprising:
 cancelling a current cycle of the dishwasher appliance if the pressure sensor output is greater than or equal to either the first pressure threshold for the predetermined time or the second pressure threshold for the predetermined time.   
     
     
         3 . The method of  claim 2 , wherein the dishwasher appliance comprises a water inlet valve, and wherein canceling the current cycle of the dishwasher appliance comprises deactivating the water inlet valve of the dishwasher appliance and deactivating the circulation pump. 
     
     
         4 . The method of  claim 1 , wherein the method further comprises:
 notifying a consumer of the flood event.   
     
     
         5 . The method of  claim 1 , wherein after activating the drain pump, the method further comprises:
 determining whether the pressure sensor output is less than or equal to a minimum pressure threshold for a predetermined time.   
     
     
         6 . The method of  claim 5 , wherein after determining whether the pressure sensor output is less than or equal to the minimum pressure threshold for the predetermined time, the method further comprises:
 deactivating the drain pump if the pressure sensor output is less than or equal to the minimum pressure threshold for the predetermined time.   
     
     
         7 . The method of  claim 5 , after determining whether the pressure sensor output is less than or equal to the minimum pressure threshold for the predetermined time, the method further comprises:
 determining whether a current time is less than or equal to a predetermined time threshold if the pressure sensor output is not less than or equal to the minimum pressure threshold for the predetermined time.   
     
     
         8 . The method of  claim 7 , after determining whether the current time is less than or equal to the predetermined time threshold, the method further comprises:
 logging a drain fault if the current time is not less than or equal to the predetermined time threshold.   
     
     
         9 . The method of  claim 7 , after determining whether the current time is less than or equal to the predetermined time threshold, the method further comprises:
 determining whether the pressure sensor output is less than or equal to the minimum pressure threshold for the predetermined time if the current time is less than or equal to the predetermined time threshold.   
     
     
         10 . The method of  claim 1 , wherein during determining whether the pressure sensor output of the pressure sensor is greater than or equal to the first pressure threshold for the predetermined time, the pressure sensor output is consecutively greater than or equal to the first pressure threshold for the predetermined time. 
     
     
         11 . The method of  claim 1 , wherein during determining whether the pressure sensor output of the pressure sensor is greater than or equal to the second pressure threshold for the predetermined time, the pressure sensor output is consecutively greater than or equal to the second pressure threshold for the predetermined time. 
     
     
         12 . The method of  claim 1 , wherein after determining that the pressure sensor output is greater than or equal to either the first pressure threshold for the predetermined time or the second pressure threshold for the predetermined time, the method further comprises:
 logging a flood fault if the pressure sensor output is greater than or equal to either the first pressure threshold or the second pressure threshold.   
     
     
         13 . A dishwasher appliance, comprising:
 a cabinet;   a tub positioned within the cabinet and defining a wash chamber for receipt of articles for washing;   one or more spray assemblies;   a circulation pump for circulating water to the one or more spray arm assemblies;   a pressure sensor;   a drain pump;   a controller communicatively coupled with the pressure sensor, the drain pump, and the circulation pump, the controller configured to:
 determine whether the circulation pump is activated; 
 determine whether a pressure sensor output of the pressure sensor is greater than or equal to a first pressure threshold for a predetermined time if the circulation pump is not activated, or, determine whether the pressure sensor output of the pressure sensor is greater than or equal to a second pressure threshold for a predetermined time if the circulation pump is activated; and 
 activate the drain pump if the pressure sensor output is greater than or equal to either the first pressure threshold or the second pressure threshold. 
   
     
     
         14 . The dishwasher appliance of  claim 13 , wherein after the controller determines whether the pressure sensor output of the pressure sensor is greater than or equal to either the first pressure threshold for the predetermined time or the second pressure threshold for the predetermined time, the controller is further configured to:
 cancel a current cycle of the dishwasher appliance if the pressure sensor output is greater than or equal to either the first pressure threshold for the predetermined time or the second pressure threshold for the predetermined time.   
     
     
         15 . The dishwasher appliance of  claim 14 , further comprising:
 an inlet water valve communicatively coupled with the controller;   wherein when the controller cancels the current cycle, the controller is configured to:
 deactivate the inlet water valve; and 
 deactivate the circulation pump. 
   
     
     
         16 . The dishwasher appliance of  claim 13 , wherein after the controller activates the drain pump, the controller is further configured to:
 determine if the pressure sensor output is less than or equal to a minimum pressure threshold for a predetermined time; and   deactivate the drain pump if the pressure sensor output is less than or equal to the minimum pressure threshold for the predetermined time.   
     
     
         17 . The dishwasher appliance of  claim 13 , further comprising:
 a communication interface communicatively coupled with the controller, and wherein when the controller cancels a current cycle of the dishwasher appliance, the communication interface is configured to:   communicate a notification that a flood event has occurred.   
     
     
         18 . The dishwasher appliance of  claim 13 , wherein the controller is further configured to:
 start a timer upon activating the drain pump;   determine, after the controller activates the drain pump, if the pressure sensor output is less than or equal to a minimum pressure threshold for a predetermined time; and   determine whether a current time provided by the timer is less than or equal to a predetermined time threshold if the pressure sensor output is not less than or equal to the minimum pressure threshold for the predetermined time.   
     
     
         19 . The dishwasher appliance of  claim 18 , wherein after the controller determines whether the current time provided by the timer is less than or equal to the predetermined time threshold, the controller is further configured to:
 log a drain fault if the current time provided by the timer is not less than or equal to the predetermined time threshold.