Warewasher deliming/descaling system

Abstract

A warewash machine includes a chamber for receiving wares, the chamber having at least one spray zone in which a liquid is recirculatable from a tank to a spray assembly for spraying the liquid on wares. A delime system is configured for delivering a delime solution to the tank. A controller is configured for operation in at least one ware cleaning mode and at least one delime operation mode. The controller is configured such that, in the delime operation mode, the delime system is controlled to carry out a delime operation in which the controller (i) controls the delime system to deliver delime solution into the tank and (ii) carries out an acidity reduction process to reduce acidity of the delime solution.

1 . A warewash machine for washing wares, comprising:
 a chamber for receiving wares, the chamber having at least one spray zone in which a liquid is recirculatable from a tank to a spray assembly for spraying the liquid on wares;   a delime system configured for delivering a delime solution to the tank;   a controller configured for operation in at least one ware cleaning mode and at least one delime operation mode, wherein, in the delime operation mode, the delime system is controlled to carry out a delime cycle in which the controller:
 controls the delime system to deliver delime solution into the tank and then circulates the delime solution; and 
 carries out an acidity reduction process to reduce acidity of the delime solution by at least one of (i) causing delivery of fresh water into the tank to dilute the delime solution in the tank or (ii) causing delivery of detergent into to the tank to effect some neutralization of the delime solution in the tank. 
   
     
     
         2 . The warewash machine of  claim 1 , wherein the controller is configured such that the acidity reduction process is carried out based upon a triggering event. 
     
     
         3 . The warewash machine of  claim 2 , wherein the controller is configured such that the triggering event is one of (i) conclusion of a delime wash/circulation timer or (ii) reaching an intermediate point of a delime wash/circulation timer. 
     
     
         4 . The warewash machine of  claim 3 , wherein the controller is configured such that, after completion of the acidity reduction process, a drain tank message is displayed on a user interface. 
     
     
         5 . The warewash machine of  claim 4 , wherein the controller is configured to monitor for draining of the tank and, if the tank is not drained within a specified time period, the machine is powered down. 
     
     
         6 . The warewash machine of  claim 5 , wherein the controller is configured such that, upon a next power up of the machine, the drain tank message is displayed on the user interface. 
     
     
         7 . The warewash machine of  claim 4 , wherein the controller is configured to monitor for draining of the tank, and operation of the warewash machine in the ware cleaning mode is prevented until draining of the tank is detected. 
     
     
         8 . The warewash machine of  claim 7 , wherein the controller monitors for draining of the tank by one of (i) monitoring of a level of liquid in the tank, (ii) monitoring a flow of liquid along a drain path from the tank or (iii) monitoring a condition of an overflow standpipe of the tank. 
     
     
         9 . The warewash machine of  claim 7 , wherein the tank includes a drain opening to a drain path, and an overflow standpipe removably engaged with the drain opening, and draining of the tank requires manual lifting of the overflow standpipe. 
     
     
         10 . A warewash machine for washing wares, comprising:
 a chamber for receiving wares, the chamber having at least one spray zone in which a liquid is recirculatable from a tank to a spray assembly for spraying the liquid on wares, the tank including a drain component that must be manually moved in order to drain the tank;   a delime system configured for delivering a delime solution to the tank;   a controller configured for operation in at least one ware cleaning mode and at least one delime operation mode, wherein, in the delime operation mode, the delime system is controlled to carry out a delime cycle in which the controller:
 controls the delime system to deliver delime solution into the tank and then circulates the delime solution; and 
 monitors whether drainage of the tank occurs after completion of circulation of the delime solution and initiates and maintains a lockout of the ware cleaning mode until drainage of the tank occurs. 
   
     
     
         11 . The warewash machine of  claim 10 , wherein at least one liquid level sensor is associated with the tank and the controller monitors output of the liquid level sensor to determine whether drainage of the tank occurs. 
     
     
         12 . The warewash machine of  claim 10 , wherein the controller is configured such that, as part of the delime cycle, an acidity reduction process is carried out to reduce acidity of the delime solution by at least one of (i) causing delivery of fresh water into the tank to dilute the delime solution in the tank or (ii) causing delivery of detergent into to the tank to effect some neutralization of the delime solution in the tank. 
     
     
         13 . The warewash machine of  claim 12 , wherein the controller is configured such that the acidity reduction process is carried out based upon a triggering event. 
     
     
         14 . The warewash machine of  claim 3 , wherein the controller is configured such that the triggering even is one of (i) conclusion of a delime wash/circulation timer or (ii) reaching an intermediate point of a delime wash/circulation timer or (iii) identifying that drainage of the tank did not occur within a set time period. 
     
     
         15 . The warewash machine of  claim 10 , wherein the drain component is an overflow standpipe.