A humidifier for an airway pressure support system for delivering a humidified flow of breathing gas to an airway of a patient, the airway pressure support system comprising a patient interface device and a gas flow generator, the gas flow generator being configured to generate the flow of breathing gas to be delivered through the patient interface device to the airway of the patient, the humidifier comprising: a water chamber structured to house a volume of water; a conduit comprising: a first end structured to be fluidly connected to the gas flow generator, an opposite second end structured to be fluidly connected to the patient interface device, and a wall portion defining an interior pathway extending between the first end and the second end, the interior pathway structured to convey the flow of breathing gas between the first end and the second end; a nozzle fluidly connected to the water chamber and having an outlet configured to produce a water droplet from water received from the water chamber; a heater plate coupled to the wall portion and exposed to the interior pathway, the heater plate having a first side facing the nozzle and an opposite second side facing away from the nozzle, the first side positioned to receive the water droplet from the nozzle; and a number of heating elements (571,573) coupled to the second side of the heater plate; characterized in that the humidifier w further comprises a thermistor coupled to the second side of the heater plate; and wherein the thermistor is disposed closer to the outlet of the nozzle than the number of heating elements are to the outlet of the nozzle. a water chamber structured to house a volume of water; a conduit comprising: a first end structured to be fluidly connected to the gas flow generator, an opposite second end structured to be fluidly connected to the patient interface device, and a wall portion defining an interior pathway extending between the first end and the second end, the interior pathway structured to convey the flow of breathing gas between the first end and the second end; a first end structured to be fluidly connected to the gas flow generator, an opposite second end structured to be fluidly connected to the patient interface device, and a wall portion defining an interior pathway extending between the first end and the second end, the interior pathway structured to convey the flow of breathing gas between the first end and the second end; a nozzle fluidly connected to the water chamber and having an outlet configured to produce a water droplet from water received from the water chamber; a heater plate coupled to the wall portion and exposed to the interior pathway, the heater plate having a first side facing the nozzle and an opposite second side facing away from the nozzle, the first side positioned to receive the water droplet from the nozzle; and a number of heating elements (571,573) coupled to the second side of the heater plate; characterized in that the humidifier w further comprises a thermistor coupled to the second side of the heater plate; and wherein the thermistor is disposed closer to the outlet of the nozzle than the number of heating elements are to the outlet of the nozzle.