DeVilbiss iFill 535D - Oxygen Sensing Device (OSD); PCB (Printed Circuit Board); Main PC Board; Power Cord

LT-1929
16
COMPONENT TESTING, REPAIR, AND REPLACEMENT
3. Reach into the iFill station and remove the long-life intake
lter and discard.
4. Insert new long-life intake lter into the intake extension
tube making sure the ler is centered in the opening.
5. Install the cylinder cradle (with ll connector cover facing
forward) by turning the 1/4 turn fasteners in the clockwise
direction.
OXYGEN SENSING DEVICE (OSD)
The onboard Oxygen Sensing Device (OSD) is mounted on the
PC board and is responsible for monitoring the oxygen purity
level being produced by the iFill station. At unit start-up, oxygen
passes through the OSD and is exhausted; it does not enter the
intensier. After approximately four minutes when the oxygen
has reached the proper purity level, the three-way valve shifts
and will begin to direct the oxygen to the inlet of the pressure
intensier. During operation, the OSD continues to monitor the
oxygen purity. If the concentration level falls below specication
of 90% (93% ± 3 %) the main PC board causes the three-way
valve to shift and prevent the oxygen from entering the
intensier.
1. The OSD is part of the Main PC board; refer to instructions
on how to replace the PCB (Printed Circuit Board).
POWER CORD
To replace the power cord (Figures 4A &14):
- 115 volt units only
NOTE–230 volt units have a detachable power cord.
1. Ensure the iFill station is unplugged from the wall outlet.
2. Remove the left and right covers from the iFill station.
3. Remove compressor and mounting plate.
4. Disconnect the power cord electrical connector and then
remove both wires (black & white) from connector housing.
5. Remove ferrite core from the end of power cord wires.
6. Loosen the power cord strain relief and push cord out of the
hole in the base of the unit.
7. Insert a new power cord through the hole and secure with
strain relief.
8. Reinsert wires into connector housing and reconnect the
power cord connector to the unit wire harness.
9. Reinstall ferrite core.
10. Replace compressor and mounting plate.
11. Replace covers.
NOTE–Be sure to reattach indicator panel
ribbon connector and hour meter electrical connector (refer
to Cover Removal and Replacement in this manual).
PRESSURE INTENSIFIER
The pneumatic pressure intensier is located in the front part of
the iFill station. The two stage intensier utilizes a large drive
piston in the power cylinder and smaller pistons in the 1st and
2nd stage cylinders to generate pressure. It receives low
pressure oxygen from the accumulator tank and increases it to
approximately 2000 PSI. The high pressure is used to ll
portable oxygen cylinders attached to the ll connector.
CAUTION–The pressure intensier must be replaced in a clean
room environment only. Tools must be kept oil free. Do not use
lubricants.
To replace the pressure intensifier (Figure 8):
1. Ensure the iFill station is unplugged from the wall outlet.
2. Remove the left and right covers from the iFill station.
3. Remove the four-way valve from the side of the intensier.
Refer to valve removal instructions.
4. Disconnect wires from terminals on pressure switch.
5. Disconnect cylinder detect switch electrical connector from
main PC board.
6. Disconnect the wire harness connector from the small
sensor hall effect board that is mounted on the side of the
intensier body.
7. Disconnect tubing from the oxygen inlet tting at the bottom
of intensier.
8. Carefully rest the iFill station on its side and remove the hex
nuts that secure the three intensier mounts to the base of
the unit. The intensier can now be removed.
9. Unscrew the three mounts from the bottom of intensier
and install them on the replacement intensier.
10. Reconnect the tubing to the oxygen inlet tting at the
bottom of the intensier.
11. Position intensier with mounts attached into the base of
the iFill station and secure with hex nuts.
12. Reconnect all wires and electrical connectors.
13. Reinstall the four-way valve.
14. Replace covers.
NOTE–Be sure to reattach indicator panel
ribbon connector and hour meter electrical connector (refer
to Cover Removal and Replacement in this manual).
PCB (PRINTED CIRCUIT BOARD)
Main PC Board
The main printed circuit (PC) board is responsible for monitoring
and controlling the DeVilbiss iFill oxygen station. In addition to
the controlling circuitry, the audible alert and oxygen sensing
device (OSD) are also located on the main PC board. The
board is mounted on the vertical piece of metal superstructure
that separates the oxygen generation system components from
the pressure intensier in the center of the unit.
To replace the main board (Figure 12):
1. Ensure the iFill station is unplugged from the wall outlet.
2. Remove the left and right covers from the iFill station.
3. Carefully disconnect tubing from the OSD.
4. Disconnect all electrical connections (6 connectors) from
the board.
5. Use a Torx screwdriver with a size T-10 bit to remove the
two retaining screws that secure the PC board to the metal
superstructure.
6. Carefully remove board from the plastic stand-offs.
7. Mount new PC board on stand-offs and secure with screws.
8. Reconnect all electrical connectors and OSD tubing.
9. Replace covers.
NOTE–Be sure to reattach indicator panel
ribbon connector and hour meter electrical connector (refer
to Cover Removal and Replacement in this manual).