A respiratory humidification system comprising: an inspiratory limb including a first segment with a first heater wire, a second segment with a second heater wire, and a temperature sensor positioned at a patient end of the second segment for measuring a patient end parameter, wherein the first and second heater wires (3906a, 3906b) are electrically coupled, the first heater wire forming a first heater circuit and the first and second heater wires (3906a, 3906b) forming a second heater circuit, the first and second heater wires (3906a, 3906b) configured to heat respiratory gases passing through the inspiratory limb; and a flow sensor in a flow path of the system and configured to measure a flow rate of the respiratory gases; wherein the first and second heater wires (3906a, 3906b) and the temperature and flow sensors are configured to be in electrical communication with a hardware processor configured to execute software instructions which cause the processor to control the first and second heater circuits, wherein, when a difference between an output of the temperature sensor and a patient end parameter set point is below a predetermined error threshold, the processor is configured to heat the respiratory gases using the first heater circuit until a maximum temperature is reached in the first heater wire, and when the difference between the output of the temperature sensor and the patient end parameter set point is at or above the predetermined error threshold, the processor is configured to heat the respiratory gases using the second heater circuit, and wherein a maximum power provided to the first heater circuit is a first maximum value or a second maximum value based on a measured flow rate, the first maximum value higher than the second maximum value. an inspiratory limb including a first segment with a first heater wire, a second segment with a second heater wire, and a temperature sensor positioned at a patient end of the second segment for measuring a patient end parameter, wherein the first and second heater wires (3906a, 3906b) are electrically coupled, the first heater wire forming a first heater circuit and the first and second heater wires (3906a, 3906b) forming a second heater circuit, the first and second heater wires (3906a, 3906b) configured to heat respiratory gases passing through the inspiratory limb; and a flow sensor in a flow path of the system and configured to measure a flow rate of the respiratory gases; wherein the first and second heater wires (3906a, 3906b) and the temperature and flow sensors are configured to be in electrical communication with a hardware processor configured to execute software instructions which cause the processor to control the first and second heater circuits, wherein, when a difference between an output of the temperature sensor and a patient end parameter set point is below a predetermined error threshold, the processor is configured to heat the respiratory gases using the first heater circuit until a maximum temperature is reached in the first heater wire, and when the difference between the output of the temperature sensor and the patient end parameter set point is at or above the predetermined error threshold, the processor is configured to heat the respiratory gases using the second heater circuit, and wherein a maximum power provided to the first heater circuit is a first maximum value or a second maximum value based on a measured flow rate, the first maximum value higher than the second maximum value.