Patent ID: 11957844
Assignee: FISHER & PAYKEL HEALTHCARE LIMITED
Field: Medical technology (Instruments)
Classification: CPC A  H | IPC A  H

Claim 14:
15. An apparatus for preparing a flow of gases including:
a humidifier including a reservoir and a heater for heating the reservoir,
a temperature sensor in thermal communication with the heater to read the temperature of the heater,
a controller adapted to apply power from a power supply to the heater, the controller including a control method comprising:
monitor system conditions during use of the apparatus,
determine a possible absence of water in the reservoir from the monitored system conditions,
following a determination of a possible absence of water,
applying a maximum available power from the power supply to the heater,
monitoring an output of the temperature sensor,
determining a water out condition if the output of the temperature sensor exceeds a predetermined threshold for a predetermined period of time,
subsequently reducing the power supplied from the power supply to the heater, and
providing an output indicating the water out condition.