Hour Meter; Molecular Sieve Beds; Power Cord; Power Switch - Sunrise Medical DeVilbiss Serie Manual De Servicio

C O M P O N E N T T E S T I N G , R E P A I R , A N D R E P L A C E M E N T

HOUR METER

To replace the hour meter (Figure 9):
1. Make sure the unit is unplugged from the wall outlet.
2. Remove the front and back cabinets and loosen the bib.
3. Disconnect the hour meter connector from the PC board.
4. Remove the meter by carefully inserting a small flat screwdriv-
er under the outer edge of meter and prying upward.
5. Install a new hour meter by applying downward pressure until
it snaps into position.
6. Connect the hour meter to the PC board.
CAUTION: Do not apply any force or flex the PC
Board when connecting or disconnecting electronic or
pneumatic components. Damage to the electronic
assembly is possible.

MOLECULAR SIEVE BEDS

The two molecular sieve beds alternately remove the nitrogen
from the air passing through them and provide the patient
with a constant supply of oxygen.
The efficiency of the molecular sieve material will be impaired
if it becomes contaminated by moisture. Contamination causes
the molecular sieve material to lose its nitrogen adsorbing
properties resulting in a decrease in oxygen concentration.The
unit should run for a minimum of 20 minutes before turning
"Off" to prevent problems associated with moisture contami-
nation in the system.
To test the sieve beds:
1. Remove the 1/16" plugged piece of tubing from the top of
each sieve bed.
2. Connect the pressure-vacuum gauges to the sieve bed test
points (Figure 9) in order to observe unit cycling and bed
pressures. Refer to the section on Normal Operating Sequence.
3. If it is determined that the valve did not shift, refer to the sec-
tion on Rotary Valve testing. However, if the unit is cycling prop-
erly allow unit to run while observing the sieve bed pressures.
4. After 20 minutes of operation, check the oxygen concentra-
tion levels. Low oxygen concentration and high pressures indi-
cate contaminated sieve beds.
NOTE: If the molecular sieve material is found to be no longer
effective, first locate the source of the malfunction or cause
(such as leaks) for contamination and take corrective action.
To replace the molecular sieve beds
1. Make sure any contamination problem has been corrected
before replacing.
2. Make sure the unit is unplugged from the wall outlet.
3. Cut the plastic cable ties that secure the sieve beds to the
internal structure of the unit.
4. Remove the tubing from the fittings at the top of each sieve bed.
5. Remove the hose clamps and hose from the bottom of the
sieve beds.
LT-1928
6. Install new sieve beds in reverse order using new plastic cable
ties. Position the new beds so that the bed serial number label
is at the top of the unit.
NOTE: Make sure that the sealing caps remain on the new
sieve beds until just prior to connecting hoses and tubing.
7. Leak test all connections with a certified leak detection solution
such as Snoop
col). Apply leak test solution to all fittings and hose connec-
tions with unit running. If an air leak is present, the solution
will bubble. All leaks should be repaired before putting the unit
back in service.
CAUTION: Do not apply leak test solution to any part
of the rotary valve or the main PC Board assembly.

POWER CORD

To replace the power cord - 115 volt units only
(Figure 4):
1. Make sure the unit is unplugged from the wall outlet.
2. Remove the back cabinet.
3. Disconnect the power cord connector.
NOTE: Loosening or removing the compressor mounting
plate may make it easier to service the power cord.
4. Note wire colors and socket locations before removing wires.
5. Using a pair of duckbill pliers, squeeze the power cord strain
relief and pull it out of the base of the unit.
6. Insert a new power cord through the hole in the base of the
unit and secure with strain relief.
7. Insert sockets into connector housing and then reconnect the
power cord connector.
8. Replace back cabinet and secure with the six screws.

POWER SWITCH

To replace the power switch (Figure 8):
1. Make sure the unit is unplugged from the wall outlet.
2. Remove the front and back cabinets and loosen the bib.
3. Note the position of the wires and switch before removing
the wires from the switch terminals.
4. While squeezing the locking tabs on the sides of the switch,
push the switch out of the front of the bib.
5. Install the new switch in the correct orientation making sure
that it locks into position.
:
(Figures 5, 6, &7)
6. Reconnect the wires to the switch terminals.

PRESSURE REGULATOR

The pressure regulator stabilizes the flow of oxygen to the
patient and establishes back pressure on the system. It is pre-
set at 8.5 psi (58.6 kPa) and should not have to be adjusted in
the field.
To test the pressure regulator:
1. Turn the unit "On."
2. Set the flow meter at 2 lpm.
18
® or equivalent (must not contain ethylene gly-