Nidek Mark 5 Nuvo Lite Service manual (2011)

Nidek Medical Products, Inc®

Mark 5 Nuvo® Lite Oxygen Concentrator

Service Manual

Nidek Medical Products, Inc. 3949 Valley East Industrial Drive

Birmingham, Alabama 35217 USA

Telephone: [phone] • 24-Hour Fax: [phone]

Nidek Medical is a trademark of Nidek Medical Products, Inc.

Mark 5 Nuvo® Lite is a registered trademark of Nidek Medical Products, Inc

2010-8405 Rev E Jan 2011 1 of 48

Table of Contents

General Safety

Instructions

Section 1.0

Introduction

1.1

1.2

1.3

Section 2.0

Operational Check and Concentration Test

2.1

Section 3.0

Patient Instructions

3.1

Section 4.0

Home Service Provider Maintenance

4.1

4.2

Section 5.0

Service

5.1

5.2

Production and Use of Oxygen
Use and Maintenance of the Device
Standards and Regulations

2

4
4
5

2.2

2.3

2.4

2.5

3.2

Home Service Provider Responsibility
Important Notice and Symbol Explanations
Functional Specifications

Description of Operation
Operation Check
Alarm System

2.3.1 Power Failure Alarm test
Oxygen Concentration Test and Specification
No Oxygen Flow Alarm test Procedure

General Instructions
Routine Maintenance by the Patient

3.2.1 Cleaning the Cabinet Air Filter

3.2.2 Checking the Alarm System Battery

Routine Maintenance

4.1.1 Cabinet Air Filter

4.1.2 Final Product Filter Replacement

4.1.3 Compressor Inlet Air Filter Replacement

4.1.4 Recording Maintenance

6
7
7

8
8
9
9
9

10

10
11
11
11

11
11
12
12
12

-

2 of 48 Jan 2011 2010-8405 Rev E

Cleaning Unit

4.2.1 Preparing for New Patient Use

Components
Cabinet Removal

5.2.1 Removing Cabinet Back

5.2.2 Caster Replacement

13
13

13
13
13
13

5.3

Compressor

5.4

5.5

5.6

5.7

5.8

5.9

5.10

5.11

5.12

5.13

5.14

5.15

6.1

6.2

6.3

6.4

6.5

5.3.1 Compressor Replacement

5.3.2 Capacitor Replacement
Process Control Valve

Sieve Bed Replacement

5.5.1 Sieve Bed Removal

5.5.2 Sieve Bed Installation
Cabinet Fan Replacement
Circuit Board Replacement

5.7.1 Circuit Board Removal

5.7.2 Circuit Board Installation
Product Regulator Check and Setting

5.8.1 Product Regulator Cleaning or Rebuilding
Pressure Switch Replacement
Circuit Breaker Replacement

5.10.1 Circuit Breaker Removal

5.10.2 Circuit Breaker Installation
I/0 (ON/OFF) Power Switch Replacement

5.11.1 I/0 (ON/OFF) Power Switch Removal

5.11.2 I/0 (ON/OFF) Power Switch Installation
Buzzer Replacement
Hour Meter Replacement
Flow Valve Replacement

5.14.1 Flow Valve Removal

5.14.2 Flow Valve Installation
Power Cord Replacement

14
15
15

16
16
16
16
17
17
17
18
18
19
19
19
19
19
20
20
20
20
20
20
20
20
21

Section 6.0

Troubleshooting

Air Pressure Test (P1)

6.1.1 High Air Pressure (P1)

6.1.2 Low Air Pressure (P1)
Product Pressure Test (P2)

6.2.1 Low Product Pressure

6.2.2 High Product Pressure
General Troubleshooting
Troubleshooting Chart
Tool Kit and Pressure Test Gauge

21
23
23
24
24
24
25
26
29

2010-8405 Rev E Jan 2011 3 of 48

Appendices

Exploded

Drawings

A-1: OCSI Pneumatic Diagram 30
A-2: Standard Pneumatic Diagram 31
A-2-A: No-Flow Alarm Pneumatic Diagram 32
A-3: 115 Volt Electrical Schematic 33
A-4: 230 Volt Electrical Schematic 34
A-5: Electrical Schematic for No Flow Board 35
A-6: Electrical & Compressor Assembly 36
A-6-A: Electrical & Compressor Assembly Parts 37
A-6-B: Compressor Mounting Bracket Parts 38
A-7: Front Cabinet Standard Assembly 39
A-7-A: Front Cabinet Standard Assembly Parts 40
A-8: Front Cabinet OCSI Assembly 41
A-8-A: Front Cabinet OCSI Assembly Parts 42
A-9: Back Cabinet Assembly 43
A-9-A: Back Cabinet Assembly Parts 44
A-10: Module Assembly 45
A-10-A: Module Assembly Parts 46
A-11: Maintenance Log 48

General Safety Instructions

Production and use of oxygen

Oxygen is not a flammable gas, but accelerates the combustion of materials. To prevent fire risks, the
MARK 5 NUVO Lite should be kept away from flames, incandescent sources or sources of heat
(including cigarettes) and combustible products such as oil, grease, solvents, aerosols, etc.

Do not use in an explosive atmosphere.
Prevent oxygen from accumulating on upholstered seats or any other fabric. If the concentrator

operates without being administered to a patient, locate it so that the flow of product gas produced is
dissipated into the air.

Locate the equipment in a free space (filter to the rear and below) which is well ventilated and free of
fumes or atmospheric pollution.

Use and Maintenance of the Device

Use the electric cable provided and check that the voltage of the mains socket used complies with the
electrical characteristics of the appliance indicated on the manufacturers plate on the rear of the
device.

4 of 48 Jan 2011 2010-8405 Rev E

Do not use an extension cord or multiple sockets which can create sparks and therefore pose a fire
risk.

Use of the MARK 5 NUVO Lite must be restricted solely to oxygen therapy on medical prescription
in compliance with the daily rate and duration.

Use in other circumstances may represent a hazard to patient health.
Do not use in a specifically magnetic environment (MRI, etc.).

The MARK 5 NUVO Lite has an audible alarm intended to warn the user of any problems. The user
must determine the maximum distance away from the Nuvo based on the on the sound levels in the
environment, to ensure that the alarm is always audible.

Standards & Regulations
In compliance with UL60601-1 [EN60601-1] (para 6.82.b):

“The manufacturer, assembler, installer or importer are not considered to be responsible for
consequences or the safety, reliability and characteristics of a device unless,

● the assembly, extensions, adjustments modifications or repairs have been performed by

persons authorized by the manufacturer,

● the electrical installation of the corresponding premises complies with appropriate regulations

and codes,

● the device is used in accordance with the instructions for its use.

If the replacement parts used for periodic servicing by an approved technician do not comply with the
manufacturer’s specifications, the manufacturer is absolved of all liability in the event of an incident.

Do not open the equipment when it is powered on: risk of electrocution.
This device complies with the requirements of the FDA Quality System Regulation and EU Directive

93/42/EEC and 2007/47/EC, but its operation may be affected by use in the surrounding area of
appliances such as diathermy, high frequency electro-surgical instruments, defibrillators, short wave
treatment appliances, cell-phones, CB devices and other portables, microwave ovens, induction hot
plates or remote control toys, and more generally, by electromagnetic interference exceeding the
levels specified in standard IEC(EN) 60601-1-2:2001.

As a regulated medical device, both manufacturers and service providers have certain responsibilities
regarding complaints.

FDA defines a complaint as any written, electronic or oral communication that alleges
deficiencies related to the identity, quality, durability, reliability, safety, effectiveness or
performance of a device that has been released for distribution.

2010-8405 Rev E Jan 2011 5 of 48

Service providers have a responsibility to evaluate any complaints received from their direct

customers. ( Ref. CFR 820.198 ). Nidek Medical does not have direct links to your customers.

Your evaluation should include the following:

● Determine if the complaint warrants action by Nidek Medical,

● If NO, resolve the complaint with your customer,

● If YES, contact Nidek Medical customer service,

● Work with Nidek Medical to resolve all complaints.

1.0 Introduction

1.1 Home Service Provider Responsibility

All Home Service Providers of the Nidek Medical MARK 5 NUVO Lite Oxygen Concentrator must
assume responsibilities for handling, operational check-out, patient instruction, and maintenance.
These responsibilities are outlined below and throughout this manual.

WARNING

MARK 5 NUVO Lite units must not be used for or with any life-supporting or life sustaining
applications. Patients unable to communicate discomfort while using this device may require
additional monitoring. Advise patients to immediately notify their Home Service Provider(s) and/or
physician(s) in case of an alarm or any discomfort.

As a Home Service Provider, you must do all of the following:

● Inspect the condition of each MARK 5 NUVO Lite unit immediately upon delivery to your
business location. Note any sign of damage, external or internal, on the delivery receipt,
and report it directly to both the freight company and Nidek Medical Products, Inc.
immediately.

● Check the operation of each MARK 5 NUVO Lite before delivery to a patient. Always
operate the unit for a reasonable length of time and check that the oxygen concentration
level is within specifications as referred to in Section 2.4. Test the power failure alarm as
described in Section 2.3 of this manual.

● Deliver MARK 5 NUVO Lite units only to patients authorized by a physician’s
prescription. The MARK 5 NUVO Lite must not be used as a life-supporting or life
sustaining device. A backup supply of oxygen must be available.

● Instruct patients and patient caregivers how to use the MARK 5 NUVO Lite in
conjunction with the Users Manual.

● Instruct patients and patient caregivers to notify their physicians and/or Home Service

Providers if they experience any signs of discomfort.

● Instruct each patient and patient caregivers how to perform routine maintenance of the

6 of 48 Jan 2011 2010-8405 Rev E

cabinet air filter and how to check the alarm system. (Refer to Section3.2.)

Describes a hazard or unsafe practice that can result in

Describes a hazard or unsafe practice that can result in

size or

Be available to service each patient at any time. Maintain the MARK 5 NUVO Lite in
accordance with Section 4.0.

Repair components and replace parts only as outlined in this manual. Use only Nidek Medical parts for
replacement in MARK 5 NUVO Lite Oxygen Concentrators.

● Refer to the MARK 5 NUVO Lite Product Warranty if parts replacement is required within
the warranty period.

1.2 Important Notice and Symbol Explanations

As you read the manual, pay special attention to the WARNING, CAUTION, and NOTE messages.
They identify safety guidelines or other important information as follows:

WARNING:

CAUTION:

NOTE:

The following harmonized symbols (pictograms), used for non-English language countries, will be
located in the User’s Guide of the MARK 5 NUVO Lite unit:

Read the accompanying documents; particularly the User's Guide.

Store, ship and use the device in an upright condition.

No smoking within five feet of this device, oxygen-carrying tubing, or
accessories.

Indicates an alarm signal for low oxygen concentration or other problem.

Do not use any oil or grease on or near the device

severe bodily injury or death.

minor bodily injury or property damage.
Provides information important enough to empha

repeat.

1.3 Functional Specifications

Dimensions: 35.6 cm long, 22.9 cm wide, 58.5 cm high

[14 in. long, 9 in. wide, 23 in. tall]

Weight: 13 kg [30 Ib] depending on sound attenuation package
Electrical 115 VAC, 60 Hz, +/- 10% <330 watts(avg)
Requirements: 230 VAC, 50 Hz, +/- 10% <300 watts(avg)

230 VAC, 60 Hz, +/- 10% <330 watts(avg) (280 W for 3 l/min unit)
Capacity: Max. 5 liters per minute ( 3 l/min for 925/60K )
Accuracy: Flow Valve ±10% indicated flow rate +/- 200 ml whichever is greater as

2010-8405 Rev E Jan 2011 7 of 48

per ISO 8359 Standard
Concentration: 2 liters per minute at >90%

5 liters per minute at 90% (+ 6.5 / - 3%)

(Based on 21°C [70°F] at sea level)
Response Time: Acceptable concentration is normally achieved in about 90 seconds;

allow 5 minutes to attain full concentration.
Positioning: Operate the unit in an upright position, maintaining at

least six inches of open space on all sides for ventilation.

2.0 Operational Check and Concentration Test

2.1 Description of Operation

Air enters the MARK 5 NUVO Lite Oxygen Concentrator through an external cabinet air filter. This
filtered air enters the compressor via a suction tube and fine filter, which quiets the suction sounds
made by the compressor. Pressurized air then exits the compressor and passes through a heat
exchanger into a pair of 3-way solenoid valves. The heat exchanger reduces the temperature of the
compressed air. Next, the solenoid valve directs the air into one of two sieve beds that contain
molecular sieve. The special characteristic property of molecular sieve is that it physically attracts
(adsorbs) nitrogen when air passes through this material, thus enabling the production of high purity
oxygen.

There are two sieve beds or adsorbent columns; while one produces high purity oxygen, the other is
purged of the nitrogen it adsorbed (collected) while it was producing oxygen. Each column produces
oxygen for approximately five seconds and delivers it to the product storage volume tank integrated
into the sieve module. Oxygen exits the product storage tank through a pressure regulator, flow
control valve, and final product filter. The flow control valve, controls the flow rate of oxygen delivered
to the patient. The MARK 5 NUVO Lite unit delivers up to 95% oxygen concentration at flow rates
from 0.125 to 5 l/min. The remaining constituents of the product gas stream are nitrogen and argon,
both of which are part of the air we breathe, are inert and are completely safe.

2.2 Operational Check

Nidek Medical runs each device through a burn in period and tests every MARK 5 NUVO Lite
Oxygen Concentrator thoroughly after manufacture before releasing for shipment. As the home
service provider, it is your responsibility to perform the following test to ensure that no damage
occurred in shipping or handling.

1. Open and inspect all concentrator cartons upon receipt. Unpack each unit and remove it from
its carton. Inspect the unit itself for damage. If the exterior of the carton is damaged, or the
unit itself is damaged, note it on the freight bill signed by the driver.

2. Plug in the power cord of the unit, and set the I/0 (ON/OFF) switch to the I (ON) position.
Check to see that the following occurs:

● The compressor runs, listen for the sound.

● Exhausted cooling air flows out of the bottom rear of the unit.

8 of 48 Jan 2011 2010-8405 Rev E

● OPTIONAL for Units Equipped with Oxygen Concentration Status Indicator (OCSI): The
OCSI green light remains off until the oxygen concentration reaches 85% ± 3% (82% ± 2%
for 50 Hz units) (approximately two minutes).

● OPTIONAL for Units Equipped with No Oxygen Flow Alarm Board: The No Oxygen Flow
board test should be preformed as in Section 2.5 of this manual.

● After performing the above steps, remove the power cord from the wall outlet. Actuate the I/0

(ON/OFF) switch to the I (ON) position and note that the audible alarm sounds intermittently.
(See Section 2.3). If the unit does not initially sound off, plug the unit in and allow the unit to
run approximately 10 minutes to charge the capacitor and repeat the test. Move the switch to
the 0 (OFF) position.

3. Turn the flow valve adjustment knob clockwise until it stops (wide open). The flow valve
should indicate 5 liters/min. and the output of the unit should be 5 liters/min. If not, refer to
Section 5.8 to adjust the product regulator.

4 Perform an oxygen concentration test, as described in Section 2.4.

2.3 Alarm System

The MARK 5 NUVO©Lite Oxygen Concentrator is equipped with a capacitor powered alarm
system, which sounds an intermittent alarm when a power failure occurs and a continuous alarm when
one or more cycle variables are not within specification. It sounds an alarm if the high or low pressure
indicators are activated or if the optional OCSI detects lower than predetermined levels of oxygen
concentration. The alarm remains on until you correct the alarm condition or you set the I/0 (ON/OFF)
switch to the 0 (OFF) position. Refer to Section 6.0 for a list of probable alarm causes.

2.3.1 Power Failure Alarm Test

To test the power failure alarm, perform the following actions:
Unplug the power cord from the wall outlet, and set the I/0 (ON/OFF) switch to the I (ON) position.
If the unit has been stored for a prolonged period, Allow unit to run for approximately 10 minutes to

charge the capacitor and re-test the unit.
This should immediately activate the intermittent audible alarm. If it does not, refer to the

troubleshooting chart in Section 6.0 of this manual.

2.4 Oxygen Concentration Test and Specification

To ensure that the output of oxygen from the device is within specification, you must perform an
oxygen concentration test. Test the unit upon delivery to a patient and at periodic intervals. Home
Service Providers, based on their expertise and documentation, may establish and implement their
own plans for checking oxygen concentration. Consult Nidek Medical’s Service and Maintenance Log
(A-11) for the recommended intervals for testing.

1. If an oxygen humidifier bottle is used, remove it from the oxygen outlet.

2010-8405 Rev E Jan 2011 9 of 48

2. Connect a calibrated oxygen concentration analyzer to the oxygen outlet.

3. Set the I/0 (ON/OFF) power switch to the I (ON) position. (It takes approximately five minutes
for the oxygen concentration to stabilize.) Take oxygen concentration readings over a period of
several minutes to reduce any cyclic variations

4. Verify that the product flow rate delivered by the unit matches the patient’s prescription and
does not exceed the capacity of the unit.

5. Disconnect the oxygen analyzer, and reconnect the humidifier bottle (if used) and any other
equipment / accessories that may be required.

6. Adjust the flow valve knob to the prescribed flow rate.

Nidek Medical MARK 5 NUVO Lite Concentration Specifications

Liter Flow Specification

2 l/min greater than 90%
5 l/min 90% + 6.5 / - 3%

NOTE:

Do not measure oxygen concentration output after the product stream passes through a humidifier
bottle. Erroneous readings will result and your oxygen concentration measuring device might be
damaged.

2.5 No Oxygen Flow Alarm Test Procedure

A No Oxygen Flow Alarm board is available as an option with the Nuvo Lite
Oxygen Concentrator. To test the function of “No Flow” alarm, follow the instructions below:

1. Turn Concentrator on and allow the unit to reach normal operating purity.

2. Adjust the Oxygen Flow to desired flow rate.

3. Block the oxygen flow at the patient outlet

4. A continuous audible alarm should sound as long as the Oxygen flow is blocked

3.0 Patient Instructions

3.1 General Instructions

It is important that patients thoroughly understand how to operate the Nidek Medical MARK 5 NUVO
Lite unit. This enables proper treatment as prescribed by a qualified, licensed physician. You must

explain that the purpose of this therapy is to alleviate symptoms. If patients experience any discomfort
or the unit alarms, they must notify their Home Service Provider and/or physician immediately. You,
as the Home Service Provider, are responsible to see that each patient receives the User's Guide.
Explain each step in the operation of the unit to the patient in reference to that guide.

10 of 48 Jan 2011 2010-8405 Rev E

3.2 Routine Maintenance by the Patient

n the grille in the back of the unit. Be

To ensure accurate output and efficient operation of the unit, the patient must perform two simple
routine maintenance tasks:

• Clean the cabinet air filter

• Check the alarm system

3.2.1 Cleaning the Cabinet Air Filter

NOTE: The patient must clean this filter weekly, as described below. The filter may require

daily cleaning if the MARK 5 NUVO Lite unit operates in a harsh environment such as a house
heated by wood, kerosene, or oil, or one with excessive cigarette smoke.

1

Remove the dirty cabinet air filter from the back of the MARK 5 NUVO

Lite unit.
2 Wash the dirty filter in warm water with household detergent, and rinse.
3 Use a soft absorbent towel to remove excess water.
4 Reinstall the clean cabinet air filter o

careful that the filter edges are under the tabs.

3.2.2 Checking the Power Alarm System

See Procedure described in Paragraph 2.3.1

4.0 Home Service Provider Maintenance

4.1 Routine Maintenance

The MARK 5 NUVO Lite unit has three filters that require inspection and scheduled maintenance or

replacement.

To ensure that the output of oxygen from the unit is within specification, you must perform an oxygen
concentration test. Test the unit upon delivery to a patient and at periodic intervals. Home Service
Providers, based on their expertise and documentation, should establish and implement their own
practices for checking oxygen concentration. The interval established may be longer or shorter than
90 days, which is the default time period recommended for providers who do not choose to establish
their own method.

Nidek Medical does not require preventive maintenance on the concentrator. You do not need to
perform any maintenance as long as the MARK 5 NUVO Lite unit remains within specifications at
the prescribed flow rate. (Refer to Section 2.4)

4.1.1 Cabinet Air Filter

The external cabinet air filter is located on the back of the unit, You can easily remove it by hand.
Instruct the patient to clean this filter weekly. (Refer to Section 3.2.1.)

2010-8405 Rev E Jan 2011 11 of 48

NOTE:

The filter may require more frequent cleaning if the MARK 5 NUVO Lite unit operates in a harsh
environment such as a house heated by wood, kerosene, or oil, or one with excessive cooking,
cigarette smoke or atmospheric dust.

4.1.2 Final Product Filter Replacement

The final product filter does not require periodic replacement; it needs to be replaced only if it restricts
oxygen flow. It is suggested that it be replaced whenever the sieve module is repaired or replaced
and after the compressor is rebuilt.

1. Set the I/0 (ON/OFF) switch to the 0 (OFF) position, and unplug the power cord.

2. Remove the cabinet back to locate the final product filter.
NOTE: Observe the position of the filter before removal.

3. Separate the silicone tubing from both sides of the filter.

4. Install the new filter with the inlet side in the same position as before. Push the tubing together
so that it overlaps the barbs of the final product filter connections.

5. Record information about the final product filter replacement in Appendix 11 of this manual and
online at www.nidekmedical.com under the ‘Maintenance Log’ tab.

6. Reinstall the cabinet back.

4.1.3 Inlet Air Filter Replacement

The inlet air filter requires inspection at each patient visit. The filter should be replaced every 2 years,
or more often depending on environment.

1. Set the unit I/0 (ON/OFF) switch to the 0 (OFF) position, and unplug the power cord.

2. Remove the cabinet air filter to locate the inlet air filter.

3. Remove filter from the unit, and replace with a new filter.

4. Record information about the filter replacement in Appendix 11 of this manual and online at
www.nidekmedical.com under the ‘Maintenance Log’ tab.

5. Reinstall the cabinet air filter.

NOTE: The filter may require more frequent cleaning if the MARK 5 NUVO Lite unit operates in a
harsh environment such as a house heated by wood, kerosene, or oil, or one with excessive cooking,
cigarette smoke or atmospheric dust.

4.1.4 Recording Maintenance

As the Home Service Provider, it is suggested that you record all routine maintenance and repairs
performed on the MARK 5 NUVO Lite unit, including hours and dates of service in Appendix 11 of
this manual and online at www.nidekmedical.com under the ‘Maintenance Log’ tab.

12 of 48 Jan 2011 2010-8405 Rev E

4.2 Cleaning Unit

Periodically, use a damp cloth to wipe down the exterior case of the MARK 5 NUVO Lite. If you use
medical disinfectants, be sure to follow manufacture’s instructions.

4.2.1 Preparing for New Patient Use

When you remove the MARK 5 NUVO Lite from a patient’s home, always dispose of the used nasal
cannula and humidifier bottle. Inspect the humidifier tube and clean or replace as needed.

Replace the cabinet air filter between each patient’s use or clean with warm soapy water if it is in good
condition. Clean this filter at least once per week or more frequently if operated in a dusty
environment.

Retest the MARK 5 NUVO Lite before you return it to your inventory.

5.0 Service

5.1 Components

The design of the Nidek Medical MARK 5 NUVO Lite Oxygen Concentrator allows for easy access
and removal of most components. This allows you to perform scheduled maintenance, repair, and
replacement of parts with minimal time and effort. The inlet air filter is conveniently located behind the
cabinet air filter on the cabinet back.

CAUTION: For your safety, be sure to set the I/0 (ON/OFF) switch to the 0

(OFF) position and unplug the power cord before you service the
MARK 5 NUVO Lite Oxygen Concentrator.

NOTE: Record all scheduled maintenance on the Maintenance Log found in Appendix 11. (Refer to
Section 4.1.4.)

5.2 Cabinet Removal

5.2.1 Removing Cabinet Back

Lay the device on its front to access the cabinet back, remove four screws, two at the top near the
handle and two near the bottom of the cabinet.

5.2.2 Caster Replacement

The casters are a push in type that does not require a fastener. Lay the device on its back to access
the casters from the bottom. Pull them straight out away from the bottom.

2010-8405 Rev E Jan 2011 13 of 48

5.3 Compressor

The compressor is the pump within the oxygen concentrator that supplies air to the separation process
performed by the sieve beds. The pressure generated by the compressor forces oxygen to flow out of
the top of the sieve columns.

The compressor is the likely cause of two potential specific problems:
a. An insufficient amount of air is supplied to the process, and

b. An excessive sound level.

● Air Supply

Compressor output refers to how much compressed air the compressor can produce. This depends
upon the model of the compressor, length of stroke, piston diameter, speed of rotation and condition of
seals. The cup seals form the seal between the piston and the cylinder wall. As the cup seals wear,
the output begins to gradually decrease.

This reduction in compressor output results in less air, and thus less oxygen, entering the sieve beds.
Therefore, the production of oxygen decreases.

Because this drop in oxygen production occurs over a long period of time, preventive maintenance on
the compressor is not required.

You can continue a patient’s therapy on the MARK 5 NUVO Lite unit as long as the oxygen
concentration level at the prescribed liter flow rate is within Nidek Medical’s specification limits. Refer
to Section 2.4.

____ ___
____ ___
____ ___
____ ___
____ ___
____ ___
____ ___
____ ___
____ ___
____ ___
____ ___
____ ___
____ ___
____ ___
____ ___
____ ___
____ ___
____ ___
____ ___
____ ___
____ ___
____ ___
____ ___
____ ___
____ ___
____ ___

Air Flow

Meter

0 to 100 l/min

Pressu re

1 bar

Pressure

Gauge

Flow

Compressor

Restrictor

Air

Filter

14 of 48 Jan 2011 2010-8405 Rev E

● Sound Level

The sound level is largely determined by the condition of the compressor’s bearings.
There are four bearings located within the compressor that allow the inner components of the

compressor to rotate. If the bearings wear to the point that they become loose and noisy, the
compressor becomes noticeably loud and needs servicing. The life of a compressor is determined
primarily by its operating temperature. It is extremely important that the inlet cooling air filters are
cleaned and replaced as required.

5.3.1 Compressor Replacement

Remove Compressor Assembly
To remove the compressor assembly for exchange, follow the steps listed below:

1. Set the unit’s I/0 (ON/OFF) switch to the 0 (OFF) position, and unplug the power cord.

2. Remove the cabinet back.

3. Disconnect the suction tube and the discharge tube.

4. Disconnect the two compressor power cable leads and the two leads to the capacitor.

5. Disconnect the two springs from the compressor support plate. Slide the compressor

assembly from the cabinet.

6. Remove compressor springs from the compressor with the two screws.

7. Remove heat exchanger from compressor.

8. Remove the heat exchanger fitting from the compressor.

Compressor Assembly Installation
To install a new compressor, follow the steps listed below:

1. Perform the compressor removal procedure in reverse order.

2. Leak test all connections.

5.3.2 Capacitor Replacement

The capacitor helps the compressor to start and run more efficiently. If the compressor cannot start,
the capacitor may be defective and require replacement. The capacitor should be replaced at each
compressor service / module replacement. To replace the capacitor, take the following steps:

1. Set the unit’s I/0 (ON/OFF) switch to the 0 (OFF) position, and unplug
the power cord.

2. Remove the cabinet back.

3. Disconnect the two leads to the capacitor and clip the tie wrap securing the capacitor.

4. To install the new capacitor, connect the leads and replace the capacitor and install a new tie
wrap.

5. Clip excess after securing capacitor.

2010-8405 Rev E Jan 2011 15 of 48