A dew point sensor system for a humidifier with a housing comprising: A) a controller comprising a dew point calculator, wherein the dew point calculator is a look-up table for calculating a real-time dew point temperature and a target heater plate temperature; B) an ambient temperature sensor which generates ambient temperature data, the ambient temperature sensor operatively-connected to the controller; C) an air pathway comprising; i) a blower within the air pathway, wherein the blower causes air to move in the air pathway; ii) an air flow sensor within the air pathway, wherein the air flow sensor generates air flow data about the air moving in the air pathway; iii) a liquid reservoir operatively-connected to the air pathway; and iv) a component selected being an air pathway temperature sensor; D) a heater plate operatively-connected to heat the liquid reservoir, wherein the heater plate comprises a heater plate temperature sensor, and wherein the heater plate temperature sensor generates heater plate temperature data; and E) an external wire which is outside of the housing of the humidifier operatively-connecting the controller and the component, wherein the ambient temperature sensor is located on the external wire, wherein the heater plate, and the heater plate temperature sensor are operatively-connected to the controller, and the blower is operatively-connected to the controller, wherein the controller is configured to receive the ambient temperature data, the air flow data, acquire a set dew point temperature, and calculate the real-time dew point temperature and the target heater plate temperature by employing the look-up table, wherein the real-time dew point temperature is calculated from the heater plate temperature data, the air flow data and the ambient temperature data, and the target heater plate temperature is calculated from the ambient temperature data, the air flow data, and the set dew point temperature. A) a controller comprising a dew point calculator, wherein the dew point calculator is a look-up table for calculating a real-time dew point temperature and a target heater plate temperature; B) an ambient temperature sensor which generates ambient temperature data, the ambient temperature sensor operatively-connected to the controller; C) an air pathway comprising; i) a blower within the air pathway, wherein the blower causes air to move in the air pathway; ii) an air flow sensor within the air pathway, wherein the air flow sensor generates air flow data about the air moving in the air pathway; iii) a liquid reservoir operatively-connected to the air pathway; and iv) a component selected being an air pathway temperature sensor; i) a blower within the air pathway, wherein the blower causes air to move in the air pathway; ii) an air flow sensor within the air pathway, wherein the air flow sensor generates air flow data about the air moving in the air pathway; iii) a liquid reservoir operatively-connected to the air pathway; and iv) a component selected being an air pathway temperature sensor; D) a heater plate operatively-connected to heat the liquid reservoir, wherein the heater plate comprises a heater plate temperature sensor, and wherein the heater plate temperature sensor generates heater plate temperature data; and E) an external wire which is outside of the housing of the humidifier operatively-connecting the controller and the component, wherein the ambient temperature sensor is located on the external wire, wherein the heater plate, and the heater plate temperature sensor are operatively-connected to the controller, and the blower is operatively-connected to the controller, wherein the controller is configured to receive the ambient temperature data, the air flow data, acquire a set dew point temperature, and calculate the real-time dew point temperature and the target heater plate temperature by employing the look-up table, wherein the real-time dew point temperature is calculated from the heater plate temperature data, the air flow data and the ambient temperature data, and the target heater plate temperature is calculated from the ambient temperature data, the air flow data, and the set dew point temperature.