Refrigerated merchandiser with glass door heat control

Abstract

A method of operating a refrigerated merchandiser. The refrigerated merchandiser includes a case that defines a product display area, and at least one door that provides access to the product display area. The method includes sensing a parameter of an ambient environment adjacent the case, delivering a signal indicative of the sensed parameter to a controller, and determining a duty cycle using the controller based on the signal indicative of the sensed parameter. The method also includes detecting a change in the sensed parameter using the controller, interrupting the duty cycle by initiating a clearing interval using the controller in response to the controller receiving the signal indicative of the change in the sensed parameter, and clearing condensation from the door during the clearing interval.

1 . A method of operating a refrigerated merchandiser including a case defining a product display area, and at least one door providing access to the product display area, the method comprising:
 sensing a parameter of an ambient environment adjacent the case;   delivering a signal indicative of the sensed parameter to a controller;   determining a duty cycle using the controller based on the signal indicative of the sensed parameter;   detecting a change in the sensed parameter using the controller;   interrupting the duty cycle by initiating a clearing interval using the controller in response to the controller receiving the signal indicative of the change in the sensed parameter; and   clearing condensation from the door during the clearing interval.   
     
     
         2 . The method of  claim 1 , further comprising
 operating the duty cycle in an “on” state for a first predetermined time;   clearing condensation from the door during the first predetermined time by applying heat to the door; and   operating the duty cycle in an “off” state for a second predetermined time.   
     
     
         3 . The method of  claim 1 , further comprising sensing at least one of temperature and humidity of the ambient environment. 
     
     
         4 . The method of  claim 1 , wherein detecting a change in the sensed parameter includes
 sensing a baseline parameter of the ambient environment using the controller; and   sensing a subsequent parameter and comparing the subsequent parameter with the baseline parameter.   
     
     
         5 . The method of  claim 1 , further comprising detecting the occurrence of a door event of the door in response to detecting the change in the sensed parameter. 
     
     
         6 . The method of  claim 1 , further comprising restarting the duty cycle after the clearing interval is complete.