A roll assembly temperature sensing system for a pellet mill includes: a thermal sensor (160); and a pellet mill roll assembly rotatably disposed in a rotor assembly. The pellet mill roll (140) assembly includes: a roll shaft; a bearing disposed circumferentially around the roll shaft; and a seal (150) disposed between an end of the bearing and the rotor assembly. The rotor assembly includes an area defining a die cavity adjacent to the seal (150). The thermal sensor (160) is disposed within the die cavity, and is configured to detect a temperature of the seal resulting from heat conducted from the bearing.