Low cost CPAP flow generator and humidifier assembly

A system for providing respiratory therapy to a patient, the system comprising:

• a housing;
• a flow generator contained within the housing that is configured to generate a supply of pressurized gas provided via an outlet formed in a side of the housing;
• a humidifier tub comprising a base plate, a humidifier inlet, and a humidifier outlet, wherein the humidifier tub defines a chamber configured to receive and retain a volume of water, wherein the humidifier inlet is configured to be fluidly coupled to the outlet to receive the supply of pressurized gas into the chamber defined by the humidifier tub;
• a heater plate configured to support the humidifier tub in an operative position for the humidifier inlet to be fluidly coupled to the outlet to receive the supply of pressurized gas, wherein the heater plate comprises a heating element that is configured to heat the heater plate and a thermistor that is configured to generate a temperature signal indicating a temperature of the heater plate, wherein humidifier outlet is configured to provide a supply of humidified pressurized gas for the respiratory therapy when the humidifier tub is supported by the heater plate in the operative position and the volume of water retained in the humidifier tub is warmed via the base plate being heated by the heater plate;
• a controller that is configured to control operation of the flow generator and the heating element to provide the respiratory therapy to the patient, wherein the controller is further configured to (i) receive the temperature signal from the thermistor, (ii) detect when volume of water has been depleted and the humidifier tub is substantially empty based, at least in part, on the temperature signal, and (iii) generate a warning in response to detecting that the humidifier tub is substantially empty;
• and
• a display configured to receive and visually output the warning generated by the controller.