DeVilbiss DV63 Standard Plus - DV6 HH Standard Humidifier; DV6 HHPD Pulsedose Humidifier

LT-2320
25
DESCRIPTION OF NORMAL OPERATION - DV6HH
DESCRIPTION OF NORMAL OPERATION
DV6HH Standard Humidifier
The heated humidier connects mechanically and electrically to a
DV6x series CPAP device between the air-stream going from the
device to the patient. The heated humidier’s output and START/
STOP functions are controlled by the CPAP device’s rotary knob and
display. Prior to operation, the humidier chamber must be lled with
water to a predened and visible water-ll level with the patient tubing
and patient interface attached to the outlet port on the heated
humidier system.
During operation, the CPAP device’s external power supply converts
AC voltage to DC voltage, and the CPAP device routes DC power to
the heater’s low-voltage circuitry contained within the CPAP device.
The humidier’s drive circuitry directs the DC power to the heating
element on the heated humidier’s heater plate. A thermistor on the
heater plate provides continuous feedback back to the control circuitry,
so that the temperature of the heater plate is consistent with the
setting selected on the CPAP device’s display.
The heated humidier’s heater plate transmits heat to the water
chamber via a heat transfer plate located on the bottom of the
chamber. As the water in the chamber heats, its evaporation efciency
increases. Air from the CPAP device passes through the chamber, is
humidied by the evaporated water and transmitted to the patient
through the patient tubing and interface.
DV6HHPD PulseDose
®
Humidifier
The optional PulseDose humidier connects mechanically and
electrically to the DV6X series CPAP device between the air-stream
going from the device to the patient. The plug-in valve module
contains an electro-mechanical PulseDose valve with a rotary valve
body that delivers humidied air while the patient inhales and,
conversely, delivers ambient room air while the patient exhales.
Patient ow, leak ow, inhalation and exhalation are continually
monitored by the CPAP device’s central processor. The timing of each
breath is calculated to ensure that the valve delivers humidied air at
the start and duration of each inhalation but delivers ambient air during
exhalation.
The valve module’s triggering algorithm works in tandem with the
central processor’s breath signal to position valve rotation so that
maximum humidity is delivered without exceeding the dew point.
Rainout, occurring when warm humidied air in the patient tube
contacts cool ambient temperatures, will normally be eliminated when
the dehumidied air clears out the humidity during exhalation.