Illinois Tool Works Inc.
Refrigeration system with evaporator temperature sensor failure detection and related methods

Abstract:

A method of automatically controlling a refrigerated device that includes a refrigeration system with an evaporator and an evaporator temperature sensor involves: (a) monitoring an output of the evaporator temperature sensor; (b) based upon monitored temperatures from (a), identifying when a rate of change in temperature indicated by the evaporator temperature sensor satisfies a set rate of change condition and determining if the temperature indicated by the evaporator temperature sensor when the rate of change satisfies to the set rate of change condition is consistent with a predefined expected temperature condition; (c) if the temperature indicated by the evaporator temperature sensor is consistent with the predefined expected temperature condition, taking a first refrigeration control action; and (d) if the temperature indicated by the evaporator temperature sensor is not consistent with the predefined expected temperature condition, taking a second refrigeration control action that is different than the first refrigeration control action.