A heater system includes an integrated heater device and a control system. The integrated heater device includes a thermocouple for measuring temperature and one or more multiportion resistive elements that are operable as heaters to create a temperature differential between the fluid and air to detect the fluid, and as sensors to measure a fluid level. The control device operates the integrated heater device as a sensor or heater based on one or more performance characteristics of the heater system and self-calibrates the heater device.