Invacare 6LXO2 User manual

INVACARE
OXYGEN CONCENTRATORS
INVACARE 5 & 6
Model 5LXO2with SensO2
Model 5LXO2Twith SensO2
Model 6LXO2with SensO2
Model 6LXO2Twith SensO2
Model 6LXO2Hwith SensO2
Model 6LXO2HTwith SensO2
INVACARE 3 & 5
Model 3LX
Model 5LX
SERVICE MANUAL
DEALER: KEEP THIS MANUAL. THE PROCEDURES IN THIS MANUAL MUST
BE PERFORMED BY AN AUTHORIZED DEALER ONLY.

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SPECIAL NOTES
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SPECIAL NOTES
WARNING/CAUTION notices used in this manual apply to hazards or unsafe practices
which could result in personal injury or property damage.
NOTICE
THE INFORMATION CONTAINED IN THIS DOCUMENT IS SUBJECT TO CHANGE WITH-
OUT NOTICE.
WARNING
DO NOT OPERATE THIS EQUIPMENT WITHOUT FIRST
READING AND UNDERSTANDING THIS MANUAL. IF YOU
ARE UNABLE TO UNDERSTAND THE WARNINGS AND
INSTRUCTIONS, CONTACT A HEALTHCARE
PROFESSIONAL (DOCTOR - THERAPIST) BEFORE
ATTEMPTING TO USE THIS EQUIPMENT - OTHERWISE
INJURY OR DAMAGE MAY RESULT.
SAVE THESE INSTRUCTIONS

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TABLE OF CONTENTS
TABLE OF CONTENTS T
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SPECIAL NOTES .................................................2
SAFETYSUMMARY .............................................4
FEATURES...... .....................................................7
SPECIFICATIONS ................................................8
Recommended End-User Guidelines
for Optimum Performance .............................9
SHIPPINGANDHANDLINGINSTRUCTIONS ...... 10
INSTALLATION / SEQUENCE OF OPERATION... 11
SENS O2 OXYGEN SENSOR TECHNOLOGY
CERAMICZIRCONIASENSOR ..................... 12
Technical Description .................................. 12
Operating Sequence.................................... 12
Pneumatic Diagram ..................................... 13
TROUBLESHOOTING GUIDE ............................ 14
REPAIR/REPLACEMENTGUIDE ........................ 21
PROCEDURE 1 - REMOVING CABINET ............. 21
PROCEDURE 2 - PREVENTIVE
MAINTENANCE.................................................. 22
Cabinet Filters ............................................. 22
Inlet Filter ..................................................... 22
Bacteria Filter .............................................. 22
Exhaust Muffler Canister/
Exhaust Muffler ........................................... 23
Cleaning Finned Heat Exchanger ................23
Compressor Top End Rebuild - 3 Liter
Rebuilding Thomas Model 2638 or
2618.......................................................... 24
Compressor Top End Rebuild - 5 and 6 Liter
Rebuilding Thomas Model 2639 or
2619.......................................................... 29
Rebuilding Thomas Model 2650................ 33
Preventive Maintenance Record .................. 37
PROCEDURE 3 - REPLACING P.E. VALVE
(5LX/6LX/5LXO2/6LXO2) ............................. 38
PROCEDURE 4 - REPLACING SIEVE BEDS ....... 39
PROCEDURE5-REPLACING CHECK VALVES .... 40
PROCEDURE 6 - REPLACING/ADJUSTING
REGULATOR ...............................................41
Replacing Regulator .................................... 41
AdjustingRegulator .................................... 42
PROCEDURE 7 - REPLACING COMPRESSOR
ASSEMBLYORCAPACITOR....................... 43
ReplacingCompressorAssembly............... 43
Replacing Capacitor ................................... 43
PROCEDURE 8 - REPLACING HEAT
EXCHANGER.............................................. 44
PROCEDURE 9 - REMOVING CONTROL
PANEL ........................................................ 45
PROCEDURE 10 - REPLACING COOLING
FAN............................................................. 46
PROCEDURE 11 - REPLACING P.C.
BOARDS..................................................... 48
PROCEDURE 12 - REPLACING
TRANSFORMERASSEMBLY ...................... 50
PROCEDURE 13 - REPLACING ON/OFF
SWITCH ...................................................... 51
PROCEDURE 14 - REPLACING
FLOWMETER ............................................. 52
PROCEDURE 15 - REPLACING HOUR
METER ....................................................... 53
PROCEDURE 16 - REPLACING 4-WAY
VALVE/MANIFOLDASSEMBLY/PILOT
VALVES ...................................................... 54
Replacing 4-way Valve ................................ 54
Replacing 4-way Valve Manifold
Assembly.................................................... 54
Replacing Pilot Valve Poppets and "O"
Rings .......................................................... 56
PROCEDURE 17 - SENSO2 ALARM
INDICATORSAND SWITCH ......................... 58
PROCEDURE 18 - TIMING INVACARE 5 AND
INVACARE6CONCENTRATORS ................ 59
PROCEDURE 19 - LEAK TEST ......................... 62
PROCEDURE 20 - ALARM AND SENSOR
TEST .......................................................... 63
PROCEDURE 21 - SIEVE BED PRESSURE
TAP-INKITINSTALLATIONANDBED
PRESSURE CHECK.................................... 67
WARRANTY ...................................................... 71

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SAFETY SUMMARY
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SAFETY SUMMARY
WARNING
The use of oxygen therapy requires that special care be taken to reduce the risk of fire. Any
materials that will burn in air, and some that will not, are easily ignited and burn rapidly in high
concentrations of oxygen. For safety concerns, it is necessary that all sources of ignition be kept
away from the product and preferably out of the room in which it is being used. NO SMOKING
signs should be prominently displayed.
A spontaneous and violent ignition may occur if oil, grease or greasy substances come in contact
with oxygen under pressure. These substances MUST be kept away from the oxygen concentra-
tor, tubing and connections, and all other oxygen equipment. DO NOT use any lubricants unless
recommended by Invacare.
For optimum performance, Invacare recommends that each concentrator be on and running for
a minimum of 30 minutes at a time. Shorter periods of operation may be harmful for maximum
product life.
If it has a damaged cord or plug, if it is not working properly, if it has been dropped or
damaged, or dropped into water, call Qualified Service Personnel for examination and repair.
Keep the cord away from HEATED or HOT surfaces.
NEVER drop or insert any object into any opening.
NEVER block the air openings of the product or place it on a soft surface, such as a bed or couch,
where the air opening may be blocked. Keep the openings free from lint, hair and the like.
Fill humidifier with water to the level shown by the manufacturer. DO NOT overfill.
Invacare recommends that Crush-Proof oxygen tubing (supplied by Invacare) be used with this
product and NOT exceed 50 ft. (15.2m) in length.
READ THE FOLLOWING INFORMATION BEFORE OPERATING THIS PRODUCT.
MAINTENANCE
The Invacare Oxygen Concentrator was specifically designed to minimize routine preventative
maintenance at intervals of once per year. Only professionals of the healthcare field or persons
fully conversant with this process such as authorized or factory trained personnel should
perform preventative maintenance or performance adjustments on the oxygen concentrator.
RADIO FREQUENCY INTERFERENCE
Most electronic equipment is influenced by Radio Frequency Interference (RFI). CAUTION should
be exercised with regard to the use of portable communications equipment in the area around
such equipment.

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SAFETY SUMMARY (Continued)
SAFETY SUMMARY
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WARNING
ALWAYS unplug this product IMMEDIATELY after using.
Avoid using while bathing. If continuous usage is required by the physicians prescription:
The concentrator must be located in another room at least seven (7) feet from the bath.
DO NOT come in contact with the concentrator while wet.
DO NOT place or store product where it can drop into water or other liquid.
DO NOT reach for product that has fallen into water. UNPLUG IMMEDIATELY.
TO REDUCE THE RISK OF ELECTROCUTION.
TO REDUCE THE RISK OF BURNS, ELECTROCUTION, FIRE OR INJURY TO PERSONS.
WARNING
This device is to be used only in accordance with the prescription of a physician and this Owners
Manual. If at any time the patient or attendant conclude that the patient is receiving an insufficient
amount of oxygen, the supplier and/or physician should be contacted immediately. No adjust-
ments should be made to the flowrate unless prescribed by a physician.
A product should NEVER be left unattended when plugged in.
Close supervision is necessary when this product is used by, on or near children or bed
confined individuals.
Use this product for only intended use as described in this manual.
DO NOT use unauthorized parts, accessories or adapters other than those authorized by
Invacare.

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SAFETY SUMMARY
SAFETY SUMMARY (Continued)
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GROUNDING INSTRUCTIONS
A. This product should be grounded. In the event of an electrical short circuit, grounding
reduces the risk of electric shock by providing an escape wire for the electrical current.
This product is equipped with a cord having a grounding wire with a grounding plug. The
plug must be plugged into an outlet that is properly installed and grounded.
DANGER
IMPROPER USE OF THE GROUNDING PLUG CAN RESULT IN A RISK OF ELECTRICAL SHOCK.
If repair or replacement of the cord or plug is necessary, do not connect the grounding wire to
either flat blade terminal. The wire with insulation having an outer surface that is green with or
without yellow stripes is the grounding wire. Check with a qualified electrician or serviceman if
the grounding instructions are not completely understood, or if doubt exists as to whether the
product is properly grounded.
B. This product is for use on a normal 120 V circuit and has a grounding plug that looks like
the plug illustrated in sketch A shown at the bottom of the page. A temporary adapter,
which looks like the adaptor illustrated in sketches B and C, may be used to connect this
plug to a 2-pole outlet as shown in sketch C if a properly grounded outlet is not available.
The temporary adaptor should be used only until a properly grounded outlet (sketch D)
can be installed by a qualified electrician. The green colored rigid ear, lug and the like
extending from the adapter must be connected to a permanent ground such as properly
grounded outlet box cover. Whenever the adapter is used, it must be held in place by the
screw.
Grounding
Pin
Tab for
Grounding
Screw
Adapter
Metal Screw
Grounded
Outlet Box
Grounded
Outlet
A B C D

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FEATURES
FEATURES
Power Switch
Elapsed Time
Meter Cabinet Filter
(2) ea.
Circuit Breaker
Oxygen Outlet
Flowmeter
Oxygen Outlet
Power Indicator
Light
Power Switch
Cabinet Filter
(2) ea.
FEATURES - 3LX, 5LX
Circuit Breaker
Flowmeter
Power Indicator
Light
Elapsed Time
Meter
SensO2 Status Indicator Lights (5LXO2,
5LXO2T, 6LXO2 and 6LXO2T ONLY)
FEATURES - 5LXO2, 5LXO2T, 6LXO2, 6LXO2T

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SPECIFICATIONS
STANDARD SPECIFICATIONS
Electrical Requirements: 120 VAC +10% (132 VAC/108 VAC), 60 Hz
Rated Current Input: 4.0 A (ALL Models)
Sound Level: 52 dB Average (3LX)
53 dB Average (5LX, 5LXO2, 5LXO2T, 6LXO2, 6LXO2T)
Operating Altitude: Up to 6,000 ft. (1828 meters) above sea level without degradation of
performance. From 6,000 ft. (1828 meters) to 13,129 ft. (4000 meters) below
90% efficiency.
Ambient Temperature Range: 50OF - 95OF (10O- 35OC)
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SPECIFICATIONS
* Stated performance maximum achieved after 30 min. of run time.
Maximum Outlet Pressure: (5LX, 5LXO2, 5LXO2T, 6LXO2, 6LXO2T) (3LX)
5 psi + 0.5 psi. 5 psi + 0.5 psi.
(34.5 kPa + 3.45 kPa.) (34.5 kPa + 3.45 kPa.)
Sens O2 Alarm Thresholds:
* Factory Preset at 73%
Indicators
O2 Purity
Over 85% (+ 2%)
73% (+ 3%) to 85% (+2%)
Below 73% (+ 3%)
Internal Switch
*Set at 73%
GREEN Indicator Light
YELLOW Indicator Light
RED Indicator Light -
Continuous Audible
Alarm Sieve GARDTM
Compressor Shutdown
Internal Switch
Set at 85%
GREEN Indicator Light
RED Indicator Light -
Continuous Audible
Alarm Sieve GARDTM
Compressor Shutdown
N/A
*Oxygen Output Concentration
Levels: ALL MODELS
95.6% to 87% at all flowrates.
If no internal selector switch, 73%
operation ONLY.
1/2 - 5 L/min. (5LX, 5LXO2, 5LXO2T, 6LXO2, 6LXO2T) 1/2 - 3 L/min. 3LX)
For flow rates less than 1/2 L/min., use the Invacare Pediatric Flowmeter
PF16.
460W (6LXO2, 6LXO2T) 350W/400W (3LX)
400W (5LX, 5LXO2, 5LXO2T)
35 psi + 3.5 psi (241 kPa + 24.1 kPa)
Flow Range:
Power Consumption:
Pressure Relief Mechanism
Operational at:

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SPECIFICATIONS, CONTINUED S
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SPECIFICATIONS
RECOMMENDED END-USER GUIDELINES FOR OPTIMUM PERFORMANCE:
Filters: Cabinet
Compressor Inlet
Bacteria
Safety Systems: Current overload or line surge shutdown.
High temperature compressor shutdown.
High pressure alarm w/compressor shutdown.
Low pressure alarm w/compressor shutdown.
Battery FreeTM Power Loss Alarm.
Sens O2 Oxygen System (5LXO2, 5LXO2T, 6LXO2, 6LXO2T ONLY).
Width: 18-inches (45.7 cm)
Height: 23.75-inches (60.3 cm)
Depth: 14-inches (35.6 cm)
Weight: 54 lbs. (24.5 kg) (All 5LX and 6LX Models) 53 lbs. (23.9 kg.) (3LX)
Shipping Weight: 59 lbs. (27 kg) (All 5LX and 6LX Models) 58 lbs. (26.1 kg.) (3LX)
Operating Temperature
Exhaust: Less than Ambient + 35OF (+16OC)
Oxygen Output: Less than Ambient + 4OF (+2OC)
Cabinet: Impact Resistant flame-retardant plastic cabinet.
Regulatory Listing: ETL certified complying with applicable portions of UL 1431
Temperature: 50O- 95OF (10O- 35OC)
Electrical: No extension cords.
Placement: No closer than 3-inches from any wall.
Tubing: Crush-Proof Tubing - 50 feet (15.2 m.) maximum (do NOT pinch).
Room Characteristics: Smoke and soot-free
No confined spaces (closet).
Relative Humidity: 20 to 60%
Time of Operation: Up to 24 hours per day.

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SHIPPING AND HANDLING INSTRUCTIONS
This Service Manual describes, in detail, the Invacare 3, 5 and 6 Oxygen Concentrators. It has been
carefully written to explain concentrator operation, service and preventative maintenance. Before
you install and operate the concentrator, please refer to OWNER'S MANUAL.
SHIPPING AND HANDLING
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The Invacare concentrator should always be kept in the upright position to prevent cabinet damage while
being transported. The shipping container has been designed to assure maximum protection of the con-
centrator.
If the concentrator is to be reshipped by common carrier, it should be packed in a new carton. Additional
cartons are available from Invacare.
The air compressor suspension system has been engineered to withstand severe motion and orientation.
UNPACKING (FIGURE 1)
1. Check for any obvious damage to the carton or its contents. If damage is evident, notify the carrier, or
Invacare.
2. Remove all loose packing from the carton.
3. Carefully remove all the components from the carton.
NOTE: After inspection, unless the Invacare Oxygen Concentrator is to be used immediately, re-
tain carton and packing materials for use in storing until use of the concentrator is required.
INSPECTION
1. Examine exterior of the Invacare Oxygen Concentrator for nicks, dents, scratches or other damages.
Inspect all components.
STORAGE
1. Store the repackaged Invacare Oxygen Concentrator in a dry area.
2. DO NOT place other objects on top of the repackaged concentrator.
FIGURE 1 - UNPACKING
Relief for Line
Cord to face
Back of Unit.
Relief for
Flowmeter
to face
Front of
Unit.

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INSTALLATION / SEQUENCE OF OPERATION
MODEL 3LX and MODELS 5LX,5LXO2, 5LXO2T, 6LXO2, 6LXO2T
INSTALLATION / VERIFICATION OF BATTERY FREETM POWER LOSS ALARM
When your new Invacare concentrator arrives, it should be checked for proper operating conditions.
1. If the unit has been in below-freezing temperatures, allow it to warm up to room temperature (approxi-
mately 30 minutes) before operating.
2. The concentrator will need to be turned on for 4 to 5 seconds to charge the Battery FreeTM Power Loss Alarm.
Connect power cord to outlet and turn the concentrator on. Turn flow control knob counterclockwise and flow will
begin immediately. Set flow rate of the Invacare 3 to 3 L/min., Invacare 5 to 5 L/min. and the Invacare 6 to 6 L/min.
Turn unit off.
3. Unplug the power cord and press On/Off switch to the ON position. An intermittent audible alarm will
sound. This confirms proper operation of the Battery FreeTM Power Loss Alarm. Turn On/Off switch
OFF.
4. Connect cord to outlet and turn on concentrator. Unit will sound 3 BEEPS on startup.
5. Check the oxygen concentration per specifications after 30-40 minutes running time.
SEQUENCE OF OPERATION
Applying 120 VAC via the power switch energizes the compressor motor, hour meter, cooling fan and the
printed circuit (P.C.) board.
Room air enters the compressor via the cabinet filter, compressor inlet filter, and sound muffler. The air is
compressed by the wobble pistons in the compressor to a pressure of 20 PSI (137.72 kPa) BEFORE
Serial No. "97K" or 21 PSI (144.79 kPa) AFTER Serial No. "97K".
As increased pressure creates increased temperature, a heat exchanger is utilized to lower the tempera-
ture by 20OF (6.7OC) before the air enters the 4-way valve. It is then channeled to a sieve bed containing
the adsorption material. A restrictor downstream of the sieve bed causes pressure to build up inside the
sieve bed which is necessary for the adsorption process. A small amount of relatively pure oxygen enters
the top of the second bed with the balance entering a storage tank. The nitrogen removed is exhausted
back from the bed through the four-way valve into room air. A muffler is located at the exhaust end of the
valve to muffle the sound of the exhaust as it exits the concentrator.
The oxygen not being used to exhaust is channeled into the storage tank. The pressurized oxygen is
regulated down to 5 PSI (34.4 kPa), enters an accurate flow-measuring device, flows through a bacterial
filter, a check valve and out to the patient.
The electrical activation of the 4-way valve is accomplished every 8 to 21 seconds by the pressure sensor
and P.C. board electronics when the pressure set point of 20 + 3 PSI (137.72 + 51.32 kPa) BEFORE
Serial No. "97K" or 21 + 3 PSI (144.79 + 51.32 kPa) AFTER Serial No. "97K" is reached. The time
between cycles is dependent on altitude, flow rate and internal environmental factors.
On the 5LX/5LXO2/5LXO2T/6LXO2/6LXO2T, a P.E. or Pressure Equalization valve opens just prior to
the shift of the 4-way valve. This allows highly concentrated oxygen to enter the just exhausted bed from
the top. This additional pressure allows the bed to start its cycle at a higher pressure. The P.E. valve will
close just after the shift of the 4-way valve.
INSTALLATION/SEQUENCE OF OPERATION
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INSTALLATION / SEQUENCE OF OPERATION, CONTINUED
If main power is lost, the Battery FreeTM Power Loss Alarm will sound a short "beep", with a long pause,
intermittently. All units are equipped with a diagnostic alarm system that signals if the pneumatic pressure
or electrical systems malfunction. The Troubleshooting Guide explains the alarm system signals and
reasons in detail for your convenience.
SENSO2 OXGYEN SENSOR TECHNOLOGY CERAMIC ZIRCONIA SENSOR
Technical Description
The oxygen being produced by the concentrator flows out of the product tank and into the flowmeter.
In-line between these components is a tee fitting that directs a small flow of oxygen through a precision
orifice to the oxygen sensor mounted on a printed circuit board.
As the oxygen enters the sensor, it passes through a screen and contacts the sensing disk.
Electric current flowing through a metal film resistor heats the disk in excess of 300O C. Oxygen molecules
contact the electrode of the disk and pick-up extra electrons to become oxygen ions. These oxygen ions
are attracted to the electrode on the bottom of the zirconia disk. Because of the crystal structure of the
zirconia, only oxygen ions can pass through. When the oxygen ions reach the bottom electrode, the extra
electrons are released from the oxygen ions and oxygen molecules return to the air. The number of
electrons is directly related to the oxygen concentration. The electrons travel to the PC board where they
are "counted" and the oxygen concentration "reading" is calculated.
A microprocessor on the P.C. board contains software that interprets the signal being received from the
sensor. It compares the signal to clinically acceptable limits that have been selected with the indicator
switch mounted on the PC board. Signals outside of the clinically acceptable limits generate responses in
the form of lighted LEDs, audible indicators, and/or system shut-down.
Operating Sequence
Once the power switch has been turned ON, the SensO2circuit will wait 5 minutes for the concentrator to
begin producing clinically acceptable oxygen before activating. No LEDs will illuminate for at least 5
minutes.
After 5 minutes, if the oxygen purity exceeds 85% + 2% the GREEN LED will illuminate.
If the oxygen level is not above 85% + 2% after the first 5 minutes, LEDs will remain off. The system will
wait for a maximum of 30 minutes from start-up to reach 85% + 2% before activating an alarm. Environ-
mental factors such as low voltage, high altitude, or age of the machine will affect the time required to
reach 85% + 2%.
If the oxygen level is not above 85% + 2% within the first 30 minutes, the oxygen concentration alarm
sequence will activate, depending upon the position of the indicator switch. All units are preset at the
factory at 73% + 3%.
When oxygen concentration is above 85% + 2%, the sensor measures oxygen purity every 10 minutes.
If a reading falls below 85% + 2% and the alarm indicator is in the 73% mode or no switch is present, the
oxygen sensor measures purity continuously and a yellow LED will illuminate. If the oxygen purity falls
below 73% + 3% the RED LED/Alarm/Shut-Down mode will activate. If the selector switch is present
and it is set at 85%, the RED LED/Alarm/Shut-Down mode will activate if the oxygen purity falls below
85% + 2%.
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INSTALLATION / SEQUENCE OF OPERATION
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PNEUMATIC DIAGRAM
PNEUMATIC DIAGRAM
INVACARE 3 & 5 OXYGEN CONCENTRATORS
MODELS IRC3LX, IRC5LX, IRC5LXO2
BACTERIA
FILTER
PRODUCT TANK
RESTRICTOR CROSSOVER
ASSEMBLY
SIEVE
BED SIEVE BED
EXHAUST
MUFFLER
HEAT
EXCHANGER
AIR
COMPRESSOR
AIR INLET
RELIEF
VALVE
PRESSURE
REGULATOR
SOLENOID PILOT
VALVE 4-WAY VALVE
CHECK VALVES
and = ELECTRICAL
CONNECTIONS
LEGEND
CABINET
(GROSS PARTICLE)
FILTER
RESONATOR
TEST POINT 1
(OXYGEN CONCENTRATOR
OUTLET)
FLOW
RESTRICTOR
P.C.BOARD
P1
TEST POINT 2
(BETWEEN PRODUCT TANK AND
CHECK VALVE)
OPTIONAL
OXYGEN
SENSOR
RESTRICTOR
ASSEMBLY
IRC3LX &
IRC5LX ONLY
FLOWMETER
RESTRICTOR
is EXTERNAL on
IRC3LX ONLY.
It is INTERNAL to
P.E. VALVE for
IRC5LX &
IRC5LXO2
5LX/5LXO2/
5LXO2T/
6LXO2/
6LXO2T ONLY
P.E. VALVE
COMPRESSOR
INLET FILTER

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SYMPTOM: PROBABLE CAUSE: SOLUTION:
NOTE: REFER TO THE REPAIR/REPLACEMENT GUIDE IN THIS MANUAL FOR PROPER
REPLACEMENT OR ADJUSTMENT PROCEDURES
NORMAL OPERATION:
Internal Status Indicators:
RED: Off GREEN: Off
Unit plugged in, power switch on.
3 "beeps" on start up.
POWER LOSS:
Internal Status Indicators:
RED: Off GREEN: Off
Unit unplugged, power switch on,
alarm off.
No problems.
POWER LOSS:
Internal Status Indicators:
RED: Off GREEN: Off
Unit plugged in, power switch on,
alarm off. "Battery FreeTM" circuit
drained.
1. No Power at outlet.
2. Power Cord.
a. Frayed.
b. Broken or damaged spade.
c. Spade connector from Power
Cord loose or disconnected
(inside back of unit).
3. On/Off switch.
a. Disconnected wire.
b. Faulty switch.
1. Check electrical outlet with a
tablelamp or voltmeter set on
150-200 VAC scale. If outlet isn't
working, check protective device
in home's electrical panel or
consult an electrician. Also
ensure that unit is properly
plugged in. DO NOT use
extension cords. Move to another
outlet or circuit.
2a.Replace cord.
2b.Replace power cord connectors
on plug.
2c.Reattach connector.
3a.Check all electrical connections
to the On/Off switch for any
disconnected wires.
3b.If the concentrator does not come
on at all and wiring is intact, color
code and remove wires one at a
time and clean the On/Off switch
with contact cleaner while turning
the switch on and off. Reinstall
switch and turn power on. If
switch still doesn't work, replace
switch. Transfer wires from old
switch to new switch one at a time
to the matching contact.
No problems. System O.K.
TROUBLESHOOTING GUIDE
TROUBLESHOOTING GUIDE
"Battery FreeTM " Circuit drained. Plug
in cord and turn power switch ON to
recharge.

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TROUBLESHOOTING GUIDE
TROUBLESHOOTING GUIDE
SYMPTOM: PROBABLE CAUSE: SOLUTION:
4. Circuit breaker.
Tripped.
POWER LOSS, Continued:
1. Transformer Assembly.
a. Faulty.
b. Connector loose or discon-
nected.
c. Faulty wiring.
2. P.C. Board.
Faulty.
INTERNAL POWER LOSS
SENSO2:
Internal Status Indicators:
RED: Off GREEN: Off
Alarm may or may not be on.
Control Panel Indicators:
RED: Off YELLOW: Off
GREEN: Off
Fan operates, power light on,
compressor not operating.
1c.Replace Transformer Assembly
(PROCEDURE 12).
HIGH PRESSURE:
Internal Status Indicators:
RED: On GREEN: Off
( LX Control Board )
RED: One (1) Flash
GREEN : Two (2) Flashes
(Integrated Sensor Board)
(LX SMT Board)
Control Panel Indicators:
RED: On YELLOW: Off
GREEN: Off
Unit plugged in, power switch on,
continuous alarm. Compressor shut
down.
1. P.C. Board.
a. Malfunction. 1a.Set flow to max l/min. for concen-
trator. Check voltage across
Pilot Valve 1 on 200 volt scale. If
meter reads 0 volts when
unit is turned on, replace P.C.
Board (PROCEDURE 11).
b. Disconnected Wire.
2. 4-way Valve
a. Not Shifting.
NOTE: REFER TO THE REPAIR/REPLACEMENT GUIDE IN THIS MANUAL FOR PROPER
REPLACEMENT OR ADJUSTMENT PROCEDURES
4. Reset breaker.
NOTE: Breaker may trip to safe-
guard concentrator during a
power surge. If breaker trips
immediately, there is a probable
short in the unit. Check for
pinched or charred wires. If the
breaker does not trip, run unit for
approximately 2 hours. If breaker
trips again, there is an internal
problem. Contact INVACARE
TECHNICAL SERVICE.
5. P.C. Board.
a. Damaged.
b. Loose or damaged connector.
5a.Replace (PROCEDURE 11).
5b.Repair or replace connector.
1a.Replace (PROCEDURE 12).
1b.Reattach connector.
2. Replace P.C. Board (PROCE-
DURE 11). For 5LX or 6LX -
Unit may require retiming after
P.C. Board replacement (PRO-
CEDURE 18).
1b.Check spade connectors on pilot
valves 1 and 2 and connectors
on P.C. Board.
1c.Replace P.C. Board (PROCE-
DURE 11). For 5LX or 6LX -
Unit may require retiming after
P.C. Board replacement (PRO-
CEDURE 18).
c. Shifting Valve at Pressures
greater than 25 p.s.i.
2a.If voltage rises to approximately
24 volts D.C. when unit
shuts down, P.C. Board is func-
tioning properly. Replace
4-way Valve (PROCEDURE 16).

16
TROUBLESHOOTING GUIDE
SYMPTOM: PROBABLE CAUSE: SOLUTION:
HIGH PRESSURE, Continued
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2.
NOTE: REFER TO THE REPAIR/REPLACEMENT GUIDE IN THIS MANUAL FOR PROPER
REPLACEMENT OR ADJUSTMENT PROCEDURES
2b.Replace 4-way Valve (PROCE-
DURE 16).
b. Bad Coil.
3. Replace Sieve Beds (PROCE-
DURE 4).
3. Sieve Beds.
Contaminated.
1. Inlet Filter
Dirty or Plugged.
2. Compressor.
a. Leaks at fittings or tubing.
b. Leaking or defective relief
valve.
c. Insufficient voltage at outlet.
d. Worn Cup Seals or Gaskets.
1. Replace Inlet Filter (PROCE-
DURE 2).
2a.Replace or repair.
2b.Repair leak or replace.
2c.DO NOT use extension cords.
Use another outlet.
2d.Rebuild Top End of Compressor
(PROCEDURE 2).
3. Heat Exchanger
a. Leak at tubing or body cham-
ber.
b. Inspect tubing and heat
exchanger.
3a.Replace or retighten.
3b.Replace or retighten tubing. Re-
place Heat Exchanger (PROCE-
DURE 8).
LOW PRESSURE:
Internal Status Indicators:
RED: On GREEN: On
(
LX Control Board )
RED: One (1) Flash
GREEN : One (1) Flash
(Integrated Sensor Board)
(LX SMT Board)
Unit plugged in, power switch
on, continuous audible alarm. Com-
pressor shut down (Failure to cycle
due to low pressure).
4. Replace (PROCEDURE 6).4. Regulator cracked or leaking.
5. P.E. Valve leaking. 5. Replace P.E. valve. Check volt
age at P.E. valve connector on 24
volt D.C. scale. The P.E.
valve activates or energizes
approximately 1 second prior to
the activation of the 4-way
Valve with approximately 24
volts. If voltage is in excess of 24
volts consistently, replace the
P.C. Board. If the P.C. Board
voltage acts normally, replace the
P.E.valve (PROCEDURE 3).
NOTE: Check for leaks starting at
the compressor output through
all the pneumatic connections.
Major leaks will cause system
pressures to remain below
adequate shift (exhaust) pres-
sures and will cause compressor
shut down.

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TROUBLESHOOTING GUIDE
SYMPTOM: PROBABLE CAUSE: SOLUTION: T
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LOW CONCENTRATION:
NOTE: Check for O2 purity
using a calibrated Oxygen Ana-
lyzer at Test Point 1 (OXYGEN
OUTLET) of the concentrator.
Internal Status Indicators:
RED: On GREEN: Off
( LX Control Board )
RED: Two (2) Flash
GREEN : One (1) Flash
73% Shutdown
(Integrated Sensor Board)
RED: Two (2) Flash
GREEN : Two (2) Flashes
85% Shutdown
(Integrated Sensor Board)
Control Panel Indicators:
SensO2 ONLY:
RED: On
YELLOW: Off
GREEN: Off
For SensO2 units, the Red indica-
tor will signal extremely low purity
and will be accompanied by a
continuous audible alarm and a
system shutdown. Repairs are
required.
Internal Status Indicators:
RED: Off GREEN: Off
( LX Control or Integrated Sensor
Board)
Control Panel Indicators:
SensO2 ONLY:
RED: Off
YELLOW: On
GREEN: Off
A Yellow indicator signals low
purity, but within specification for the
user. Repairs are required.
NOTE: REFER TO THE REPAIR/REPLACEMENT GUIDE IN THIS MANUAL FOR PROPER
REPLACEMENT OR ADJUSTMENT PROCEDURES
1. Clean or Replace (PROCEDURE
2).
2. Replace (PROCEDURE 2).
1. Cabinet Filters Dirty.
3. Compressor.
a. Defective.
b. Faulty Capacitor.
c. Bad Motor Windings.
d. Worn Seals.
e. Bad Bearings.
f. Leak at fittings or tubing.
3a.Replace Compressor (PROCE-
DURE 7).
3b.Replace Capacitor (PROCE-
DURE 7).
3c.Replace Compressor (PROCE-
DURE 7).
3d.Rebuild Top End of Compres-
sor (PROCEDURE 2).
3e.Replace Compressor (PROCE-
DURE 7).
3f. Replace Fittings or Tubing.
2. Inlet Filter Dirty.
4. Heat Exchanger.
a. Leak at tubing or body cham-
ber.
4a.Replace or Retighten.
4b.Replace or retighten tubing.
Replace Heat Exchanger (PRO-
CEDURE 8).
b. Inspect tubing and Heat
Exchanger.
7a.Leads to fan Disconnected.
Reconnect (PROCEDURE 10).
7b.Replace (PROCEDURE 10).
8. Replace (PROCEDURE 4).
9. Repair or replace.
10a.Check pressure at product tank.
Pressure should rise to 20 p.s.i.
at shift point. If not, replace P.C.
Board (PROCEDURE 21).
10b.Inspect tubing at transducer and
at product tank. Replace tubing
ONLY if damage is evident.
(PROCEDURE 9).
b. Pressure transducer tubing
leaks.
g. Leaky or Defective Relief
Valve.
h. Insufficient voltage (outlet).
3g.Replace Relief Valve.
3h.DO NOT use extension cords.
5. Replace (PROCEDURE 6).
6. Replace (PROCEDURE 2).
5. Regulator Cracked or Leaking.
6. Exhaust Muffler dirty or plugged.
7. Fan
a. Not Operating. Unit overheat-
ing.
b. Faulty Fan.
8. Sieve Beds defective
9. Tubing kinked or blocked.
10.P.C. Board
a. Shifts at wrong pressures.

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TROUBLESHOOTING GUIDE
SYMPTOM: PROBABLE CAUSE: SOLUTION:
11.Flowmeter.
a. Flowmeter opened beyond
maximum flow rate.
b. Cracked or broken Fitting.
c. Input tubing leaking or loose.
12.Timing.
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14. Replace P.C. Board. Unit may
need retiming after board
replacement (PROCEDURE
11).
13. P.E. Valve.
a.Bad Coil.
b.Restrictor Blockage.
14. Inspect P.C. Board Restrictor
tubing for kinks or tears.
FLUCTUATING FLOW:
NOTE: REFER TO THE REPAIR/REPLACEMENT GUIDE IN THIS MANUAL FOR PROPER
REPLACEMENT OR ADJUSTMENT PROCEDURES
1. Regulator/Flowmeter.
a. Incorrectly set regulator.
b. Flowmeter malfunction.
UNIT EXCESSIVELY LOUD:
1a.Replace. (PROCEDURE 2).
2a.Install new resonator.
2b.Reconnect tubing or replace.
1. Pneumatic Exhaust.
a. Muffler cracked, damaged or
missing.
b. Muffler tubing disconnected or
damaged.
2. Intake Resonator.
a. Damaged or missing.
b. Tubing disconnected or dam-
aged.
3. Inlet Filter missing.
4. Compressor.
12. To accommodate for varying
tolerances when replacing com-
ponents, an adjustable timer is
used to control the shifting of the
Invacare 5 Pressure Equaliza-
tion (P.E.) Valve (PROCE-
DURE 18).
13a.Replace P.E. Valve (PROCE-
DURE 3).
13b.Replace P.E. Valve (PROCE-
DURE 3).
1a.Check pressure at oxygen outlet.
Adjust Regulator (PROCEDURE
6).
1b.If flow is still unstable, check for
leaks starting at the compressor
outlet fitting through all pneumatic
connections. If no leaks are found
and flow is still fluctuating, replace
the regulator (PROCEDURE 6).
If pressure at test point is within
spec (5 p.s.i. + 0.2 max. [34.4 kPa
+ 6.89]), replace flowmeter
(PROCEDURE 14).
1b.Reconnect or replace tubing.
3. Replace inlet filter.
4. Replace Compressor. Internal
damage (PROCEDURE 7).
11a.Return flow to maximum setting.
11b.Replace fitting.
11c. Repair or replace.
LOW CONCENTRATION,
Continued:
2. Bacteria Filter
a. Dirty or Plugged
2a. If low flow conditions persists,
replace bacteria filter.

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TROUBLESHOOTING GUIDE
SYMPTOM: PROBABLE CAUSE: SOLUTION:
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NOTE: REFER TO THE REPAIR/REPLACEMENT GUIDE IN THIS MANUAL FOR PROPER
REPLACEMENT OR ADJUSTMENT PROCEDURES
UNIT OVERHEATS: 1. Base Exhaust Vent Plugged or
restricted.
1. Place unit at least 3-inches from
any wall. DO NOT place unit on
pile or shag carpeting that may
restrict air flow.
2. Clean or replace (PROCEDURE
2).
2. Cabinet Filters Dirty or blocked.
3a.Reconnect leads.
3b.Replace fan (PROCEDURE 10).
3c.Install fan with air flow arrow
pointing down (PROCEDURE
10).
4a.Clean heat exchanger (PRO-
CEDURE 2).
4b.Replace heat exchanger (PRO-
CEDURE 8).
3. Fan.
a. Leads to fan disconnected.
b. Defective Fan.
c. Fan installed upside down.
4. Heat Exchanger.
a. Fins dirty or plugged.
b. Fins damaged.
5. Compressor.
a. Defective.
b. Faulty capacitor.
c. Bad motor windings.
d. Worn seals.
e. Bad bearings.
6. Line Voltage excessive (surge). 6. Have line voltage inspected by
certified electrician. A voltage
regulator may be required and is
obtainable from your local elec-
tric company.
5a.Replace compressor (PROCE-
DURE 7).
5b.Replace capacitor (PROCE-
DURE 7).
5c.Replace compressor (PROCE-
DURE 7).
5d.Replace compressor (PROCE-
DURE 7).
5e.Replace compressor (PROCE-
DURE 7).
OXYGEN PURITY: GOOD
Internal Status Indicators:
RED: Off GREEN: Off
Control Panel Indicators:
RED: Off YELLOW: Off
GREEN: Off
Purity Switch setting at 73% or
85%: After 30 minutes of run time,
unit operates normally, oxygen
purity within normal range. Green
or Yellow panel indicator should
illuminate.
1. P.C. Board defective. 1. Replace P.C. Board (PROCE-
DURE 11). Unit may need
retiming after P.B. Board
replacement (PROCEDURE 18).

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TROUBLESHOOTING GUIDE
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UNIT NOT OPERATING
ALARM: OFF
Internal Status Indicators:
RED: Off
GREEN: Off
CONTROL PANEL INDICATORS:
RED: Off
YELLOW: Off
GREEN: Off
Purity Switch setting at 73% or 85%.
TROUBLESHOOTING GUIDE
NOTE: REFER TO THE REPAIR/REPLACEMENT GUIDE IN THIS MANUAL FOR PROPER
REPLACEMENT OR ADJUSTMENT PROCEDURES
1. Replace P.C. Board. (PROCE-
DURE 11). Unit may need
retiming after board replacement.
(PROCEDURE 18).
2. Reattach horn connector to
harness.
2. Horn.
Disconnected.
1. Purity Switch.
Defective.
SYMPTOM: PROBABLE CAUSE: SOLUTION:
1. Transformer Assembly.
a. Molex connector disconnected
from P.C. Board.
b. Faulty transformer assembly.
UNIT NOT OPERATING,
Internal Status Indicators:
RED: Three (3) Flashes
GREEN: One (1) Flash
(Integrated Circuit Board)
Control Panel Indicators:
RED: Off
YELLOW: Flashing
GREEN: On
UNIT NOT OPERATING,
Internal Status Indicators:
RED: Off
GREEN: Off
Control Panel Indicators:
RED: Off
YELLOW: Off
GREEN: Off
Power Switch ON. Continuous
audible alarm.
1. Internal repairs required.
1a.Reattach connector.
1b.Replace transformer assembly
(PROCEDURE 12).
1. Replace SensO2 circuit board
(PROCEDURE 11).