I zero this variable in initTemperatures(). I only check if it is zero so I can get the and start counting. I have created a delay before I go to getADCRead() state. Before I go to the next state, I zero the variable to be used again.
This is reachable, before I move to this state, I set this variable to 0. Then for the first time it will be 0 and a time is set. Once the time has elapsed, the inlet temperature is checked and the variable is set to 0 for another round of checking.