In the industrial heater industry, it’s important to note that most common oils don’t “freeze” in the traditional sense but rather thicken and become less flowable at lower temperatures. Depending on the type, oils like hydraulic, motor, or synthetic variants can begin to solidify or gel anywhere between -10°C to -50°C (-14°F to -58°F). Maintaining proper heating is essential to ensure optimal flow and performance in cold environments.