Liberator - G4

Technical Service ManualI Preface

I
Liberator

SERVICE MANUAL

LIBERATOR SERIES—G4
LIB20, LIB30, LIB37, LIB45, LIB60CAIRE, Inc.
2200 Airport Industrial Dr., Ste. 500
Ball Ground, GA 30107
www.caireinc.com
Customer/Technical Service:North and South America
Phone (US Only):
800-482-2473
US:
770-721-7759
Asia, Australia, Pacific Rim
Phone:
770-721-7759
EuropePhone:+44 (0) 1189 367060

Fax: 888-932-2473
Fax: 770-721-7758
Fax: 770-721-7758
Fax: +44 118 9799245

For Customer or Technical Service needs (product assistance, ordering, part numbers, specifications, unexpected events, etc.) contact:
CAIRE Inc.
2200 Airport Industrial Dr., Ste. 500
1-800-482-2473
www.caireinc.com

Disclaimer
This manual is intended for use by experienced personnel only. No attempt should be made to fill or maintain this equipment
until both this manual and the Patient Operating Instruction booklet have been read and fully understood.

Liberator Technical Service Manual • PN 13350704 Rev M

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I Preface

I
PRV
QDV
RMA
RP
RR
SRV
O2
SF
PTFE

Liberator

Abbreviations
FCV Flow Control Valve
LED Light Emitting Diode
LOX Liquid Oxygen
LPM Liters Per Minute
NER Normal Evaporation Rate
POI Patient Operating Instructions
N2 Nitrogen Gas
TF Top Fill
DF Dual Fill
DISS Diameter Index Safety System

Primary Relief Valve
Quick Disconnect Valve
Return Materials Authorization
Repair Procedure
Removal and Replacement
Secondary Relief Valve
Oxygen Gas
Side Fill
Polytetrafluoroethylene (“Teflon”)

Definition of Terms
WARNING Description of a condition that can result in personal injury or death.
CAUTION Description of a condition that can result in equipment or component damage.
NOTE
A statement containing information important enough to emphasize or repeat.
(ITEM)
Item numbers used throughout this manual are shown on the illustrations beginning on page 34.
Definition of Product Symbols
Table 1: Definition of Product Symbols
SymbolIP21

Definition

SymbolDefinition

Reservoir Full

Do not smoke near unit

Reservoir Empty

Keep unit well ventilated at all
times

Portable Full

Do not touch frosted parts

Portable Empty

Keep unit in upright position

Low Battery (9VDC)

CE Mark

Classification according to the degree of protection against ingressof water.

Read user manual before operation. See user manual for instructions

Type BF (Electrical Safety)

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II Table of Contents

II. Table of Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3

Liberator

I. Preface . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1
III. Equipment Description . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4
IV. Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5
V. Safety . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6
VI. Theory of Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .11
VII. Unpacking and Setup . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .14
VIII. Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .15
IX. Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .17
X. Troubleshooting . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .19
XI. Troubleshooting Charts . . . . . . . . . . . . . . . . . . . . . . . . . 20–23
XII. Repair Procedures . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .24
XIII. Service Tools/Equipment/Supplies . . . . . . . . . . . . . . . . . . .39
XIV. Parts Price List. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .40
XV. Ordering Information. . . . . . . . . . . . . . . . . . . . . . . . . . . . . .41
XVI. Return & Restocking Policy. . . . . . . . . . . . . . . . . . . . . . . . .42

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III Equipment Description
1. Cryogenic Container – This assembly is a double walled,
vacuum insulated dewar for storing liquid oxygen (LOX) atapproximately -173°C (-280° F). The inner vessel is designed
to safely hold liquid oxygen and is protected from over pressurization by the primary relief valve. Vacuum insulation
between the inner and outer vessel keeps outside heat from
causing the cold liquid inside to evaporate.

Liberator

FIGURE 1: Liberator Components

2. Breathing Circuit – This circuit consists of the manifold assembly, fixed orifice rotary flow control valve (FCV), breathing coil, and warming coil. It withdraws liquid oxygen fromthe cryogenic container, warms it to near ambient temperature, and regulates the flow of oxygen gas to the patient. Any
water that condenses on the cold coils is routed into the condensate bottle. An economizer regulator is utilized to conserve LOX by drawing oxygen head gas into the breathing
circuit.
3. Shroud Assembly – The shroud assembly houses and protects the breathing circuit and liquid level meter. Labels listing safety information and patient operating instructions areaffixed to the side of the shroud.
4. Liquid Level Meter – This system uses a capacitance probe
and an electronic (LED) readout to measure and display the
LOX level by pressing the onboard operate button.
An optional roller base can be provided to help move the
Liberator.

Serial Number Information* For Top Fill or Dual Models Only

For Liberators manufactured before 2006, the serial number
was ten digits. The first three digits represented CAIRE
specific information, followed by two digits signifying theyear of manufacture, followed by a two digit number to digit
number to signify the week of the year that the unit was
manufactured and ends with three digits signifying the unit's
production number for that week.

The CAIRE Liberator® is the stationary component of the
Liberator/Portable supplementary oxygen system. The Liberator
incorporates a stainless steel cryogenic container with the valves,plumbing, and associated hardware required to deliver gaseous
oxygen to the patient at near ambient temperature.
The Liberator is comprised of four major assemblies, grouped
according to function.

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4

IV
I Specifications (Nominal Values)
MODEL

LIBERATOR 20

LIBERATOR 30

LIBERATOR 37

LIBERATOR 45

LIBERATOR 60

Volume of LOX(typical)

21.0 liters / .021 m3

31.0 liters / .031 m3

37.3 liters / .0373 m3

45.7 liters / .0457 m3

60.2 liters / .0602 m3

Weight of LOX at 24
23kg (50.7 lbs)
psig (166 kPa) Saturation (typical)

33.9 kg (74.8 lbs)

40.8 kg (90 lbs)

50.04 kg (110.3 lbs)

65.9 kg (145.3 lbs)

Gasous Oxygen
Equivalent @ 1atm
and 70F

17,337 liters / 612 ft3

25,580 liters / 903 ft3

31,121 liters / 1099 ft3

37,724 liters / 1332 ft3

49,679 liters / 1754 ft3

Height62.2 cm / 24.5 in

74.9 cm / 29.5 in

83.2 cm / 32.75 in

94.0 cm / 37 in

99.1 cm / 39 in

Diameter

35.6 cm / 14 in

35.6 cm / 14 in

35.6 cm / 14 in

35.6 cm / 14 in

40.6 cm / 16 in

Empty Weight

17.69 kg / 39 lbs

22.04 kg / 48.6lbs

22.68 kg / 50 lbs

24.95 kg / 55 lbs

34.19 kg / 75.4 lbs

Full Weight

40.69 kg / 89.7 lbs

55.94 kg / 122.32 lbs

63.48 kg / 140 lbs

74.99 kg / 165.32 lbs

100.1 kg / 220.68 lbs

Outlet Pressure

1.4 bar / 20 psi

1.4 bar / 20 psi

1.4 bar / 20 psi

1.4 bar / 20 psi

1.4 bar / 20 psi

Nominal Operating /Economizer Pressure

1.4 bar / 20 psi

1.4 bar / 20 psi

1.4 bar / 20 psi

1.4 bar / 20 psi

1.4 bar / 20 psi

Density (Weight of
1.095 kg/L or
LOX) @ Nominal Op- 2.413 lbs/L
erating/Economizer
Pressure

1.095 kg/L or
2.413 lbs/L

1.095 kg/L or
2.413 lbs/L

1.095 kg/L or
2.413 lbs/L

1.095 kg/L or
2.413 lbs/L

Primary Relief Valve
Opening Pressure

1.6 bar / 23.2 psi

1.6 bar / 23.2 psi

1.6 bar / 23.2 psi

1.6 bar / 23.2 psi

1.6 bar / 23.2 psi

Primary Relief Valve
Reseat Pressure

1.4 bar / 20.5 psi

1.4 bar / 20.5 psi

1.4 bar / 20.5 psi

1.4 bar / 20.5 psi

1.4 bar / 20.5 psiSecondary Relief
Valve Opening
Pressure

2.1 bar / 30.5 psi

2.1 bar / 30.5 psi

2.1 bar / 30.5 psi

2.1 bar / 30.5 psi

2.1 bar / 30.5 psiSecondary Relief
Valve Reseat Pressure

1.9 bar / 27 psi

1.9 bar / 27 psi

1.9 bar / 27 psi

1.9 bar / 27 psi

1.9 bar / 27 psi

Normal Evaporation
Rate (NER - typical).73 kg / 1.6 lbs.73 kg / 1.6 lbs.73 kg / 1.6 lbs.73 kg / 1.6 lbs.73 kg / 1.6 lbs

Maximum Outlet
Flow

15 L/min

15 L/min

15 L/min

15 L/min

15 L/minContents Indicator

Capacitance Probewith LED Readout

Capacitance Probewith LED Readout

Capacitance Probewith LED Readout

Capacitance Probewith LED Readout

Capacitance Probewith LED Readout

Operating Temperature

10°C to 40°C 95%
10°C to 40°C 95%
10°C to 40°C 95%
10°C to 40°C 95%
10°C to 40°C 95%
max. relative humidity max. relative humidity max. relative humidity max. relative humidity max. relative humidity

Storage Temperature-40°C to 70°C 95%-40°C to 70°C 95%-40°C to 70°C 95%-40°C to 70°C 95%-40°C to 70°C 95%
max. relative humidity max. relative humidity max. relative humidity max. relative humidity max. relative humidity

Liberator

LIBERATOR SPECIFICATIONSNote:All specifications are applicable for G4 Liberator only and based upon optimum environmental andpressure conditions as stated above.
Listed capacities have incorporated a 2% ullage in compliance with ADR requirements.
At optimum operating conditions, the conversion factor of liquid oxygen to gaseous oxygen is 1:860.

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V Safety
WARNING: Excess accumulation of oxygen creates an oxygenenriched atmosphere (defined by the Compressed Gas
Association as an oxygen concentration above 23%). In an
oxygen-enriched atmosphere, flammable items may burnvigorously and may ex-plode. Certain items considered noncombustible in air may burn rapidly in such an environment.
Keep all organic materials and other flammable substancesaway from possible contact with oxy-gen; particularly oil, grease,kerosene, cloth, wood, paint, tar, coal dust, and dirt which may
contain oil or grease. DO NOT permit smoking or open flamein any area where oxygen is stored, han-dled, or used. Failure
to comply with this warning may result in serious personal
injury.

These hazards require certain safety precautions to be taken whenworking with or around gaseous and/or liquid oxygen:

WARNING: In the event a unit is dropped, tipped over, or unreasonably abused, immediately, but cautiously, raise the container
to its normal vertical position. If substantial container damage
has occurred, remove the liquid oxygen from the vessel in a safemanner (RP23). Purge the unit with an inert gas (nitrogen) andpromptly return it to CAIRE for inspection. The container should
be prominently marked “CONTAINER DROPPED, INSPECT
FOR DAMAGE.” Failure to comply with these procedures may
result in personal injury and can seriously damage the container.

1. Never permit combustible substances such as greases, oils,
solvents, or other compounds not oxygen compatible tocontact any component of the unit exposed to higher-thanatmospheric concentrations of gaseous or liquid oxygen. This
especially applies to tubing, fittings, and valves.
2. Keep oxygen equipment away from open flames or electricalappliances such as heaters, stoves, toasters, and other devices
with heating elements.
3. Never permit smoking in an area where oxygen equipment isrepaired, filled, or used.
4. Always wear goggles, a face shield, and insulated gloves whenworking with or around liquid oxygen.
While CAIRE, Inc. equipment is designed and built to the mostrigid standards, no piece of mechanical equipment can ever bemade 100% foolproof. Strict compliance with proper safety practices is necessary when using any Liberator unit. We recommendthat our distributors emphasize safety and safe handling practices
to their employees and customers. While safety features have been
designed into the unit and safe operations are anticipated, it is necessary that all distributor personnel carefully read and fully understand WARNINGS, CAUTIONS, and NOTES throughout the
manual. Periodic review of this information is recommended.

CAUTION: The Liberator should be moved by utilizing the rollerbase or hand truck. Do not roll units on their side or edge as insulation damage can occur. The Liberator must be used, stored,
and transported in a vertical position. Do not lay, store, or ship
the unit on its side.

Liberator

Oxygen, as it exists at standard atmospheric pressure and temperature, is a colorless, odorless, and tasteless gas. Oxygen constitutes
21% of the atmosphere, by volume. Aside from its well-documented ability to sustain life, oxygen also supports combustion,even though it is nonflammable. Many substances which will burnin air burn at a faster rate and at a higher temperature in an oxygen-enriched atmosphere. Other materials that do not burn in air
will burn as oxygen concentration increases. Additionally, many
greases and liquid solvents become extremely hazardous materials when placed in an oxygen-enriched environment. In its liquid
form, oxygen is still odorless and tasteless, but is pale blue in color.
At an operating pressure of 1,4 bar (20 psig), the temperature ofliquid oxygen is about -173°C (-280° F). Skin exposed to such a lowtemperature can become severely frostbitten.

WARNING: Personnel must remove liquid oxygen and depressurize the unit before removing parts or loosening fittings froma unit. Failure to do so may result in personal injury from theextreme cold of liquid oxygen and/or the pressure in the vessel.
WARNING: During transfer of liquid oxygen, components will
become extremely cold. Care should be used to avoid any contact
with these components, as serious frostbite may result.
WARNING: During transfer of liquid oxygen gas blowoff fromthe vent valve creates a loud horn-like noise. Ear protection isrecommended.
WARNING: Keep filled unit upright at all times. Tip over of filledunit may result in liquid oxygen leakage and/or an oxygen-enriched atmosphere.
WARNING: Only use replacement equipment which is compatible with liquid oxygen and has been cleaned for oxygen use. Do
not use regulators, fittings, hoses, etc. which have been previously
used in non-oxygen service.
WARNING: This product can expose you to chemicals
including Nickel, which is known to the State of California tocause cancer. For more information, go to
www.P65Warnings.ca.gov.

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V Safety
WARNING: The use of Accessories, transducers, and cables otherthan those specified by the manufacturer may result in increased
Emissions or decreased immunity of the Liberator.

WARNING: Portable and mobile RF communications equipment
can affect Medical Electrical Equipment.

WARNING: The Liberator should not be used adjacent to or
stacked with other equipment, and that if adjacent or stacked use
is necessary, the Liberator should be observed to verify normal operation in the configuration in which it will be used.

Liberator

WARNING: Medical electrical Equipment needs special precautions regarding EMC and needs to be installed and put into service
according to the EMC information provided in this manual.

Table 1
Guidance and Manufacturer’s declaration—electromagnetic emissions
The Liberator is intended for use in the electromagnetic environment specified below. The customer or the user of the Liberator should
assure that it is used in such an environment.
Emissions test

Compliance

RF emissions

Group 1CISPR 11		

Electromagnetic environment—guidance
The Liberator uses RF energy only for internal function.
Therefore, its RF emissions are very low and are not likely tocause any interference in nearby electronic equipment.

RF emissions CISPR 11

Class B

Harmonic emissions
IEC 61000-3-2

The Liberator is suitable for use in all establishments, including
Not applicable

Voltage fluctuations/		
flicker emissions

domestic establishments and those directly connected to the public
low-voltage power supply network that supplies buildings used for

Not applicable

domestic purposes.

IEC 61000-3-3

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V Safety
Liberator

Table 2
Guidance and manufacturers declaration—electromagnetic immunity
The Liberator is intended for use in the electromagnetic environment specified below. The customer or the user of the Liberator should
assure that it is used in such an environment.
Immunity test
Electrostatic
discharge (ESD)

IEC 60601 t

Compliance level±6 kV contact±6 kV contact±8 kV air

±8 kV air

IEC 61000-4-2			

Electromagnetic environment—guidance
Floors should be wood, concrete or ceramic tile. If floors
are covered with synthetic material, the relative
humidity should be at least 30%.*

Electrical fast

±2 kV for powerNot applicabletransient/burst

supply lines

DC powered device

IEC 610004-4±1 kV forNot applicable		Not applicable

input/output lines No data input/output lines±1 kV line(s)SurgeIEC 61000-4-5

to line(s)Not Applicable±2 kV line(s)DC powered device

Not Applicableto earth
Voltage dips,<5% UT (>95% dip		short interruptionsin UT) for 0,5 cycle		and voltage

40% UT (60% dip		variations on

in UT) for 5 cycles

Not Applicable

power supply

70% UT (30% dip

DC powered device

input lines

in UT) for 25 cycles		IEC 61000-4-11<5% UT (>95% dip

Not Applicablein UT) for 5 sec
Power frequency

3 A/m

3 A/m

Power frequency magnetic fields should be at levels(50/60 Hz)

characteristic of a typical location in a typicalmagnetic fieldcommercial or hospital environment.

IEC 61000-4-8
Note: UT is the a.c. mains voltage prior to application of the test level.

* This statement indicates that the required testing was performed in a controlled environment and the Liberators are found to be compliant with regulations.

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V Safety
Guidance and manufacturers declaration—electromagnetic immunity

Liberator

Table 4*

The Liberator is intended for use in the electromagnetic environment specified below. The customer or the user of the Liberator
should assure that it is used in such an environment.
Immunity test
Conducted RF
IEC 61000-4-6

IEC 60601 test level
3Vrms
150kHz to 80 MHz

Compliance level
Not Applicable
Battery powered
deviceRadiated RF
IEC 61000-4-3

3 V/m
80 MHz to 2,5 GHz		

3 V/mElectromagnetic environment—guidancePortable and mobile RF communications equipment should
be used no closer to any part of the Liberator, including
cables, than the recommended separation distancecalculated from the equation applicable to the frequencyof the transmitter.
Recommended separation distanced = 1.2 √P
d = 1.2 √P 80 MHz to 800 MHz
d = 2.3 √P 800 MHz to 2,5 GHz
where P is the maximum output power rating of thetransmitter in watts (W) according to the transmitter
manufacturer and d is the recommended separation
distance in meters (m).
Field strengths from fixed RF transmitters, as determinedby an electromagnetic site surverya, should be less thanthe compliance level in each frequency rangeb.
Interference may occur in the vicinity of equipment marked
with the following symbol:

NOTE 1 At 80 MHz and 800 MHz, the higher frequency range applies.
NOTE 2 These guidelines may not apply in all situations. Electromagnetic propagation is affected by absorption and reflection
from structures, objects and people.
Field strengths from fixed transmitters, such as base stations for radio (cellular/cordless) telephones and land mobile radios,amateur radio, AM and FM radio broadcast and TV broadcast cannot be predicted theoretically with accuracy. To asses the electromagnetic environment due to fixed RF transmitters, an electromagnetic site survey should be considered. If the measured fieldstrength in the location in which the Liberator is used exceeds the applicable RF compliance level above, the Liberator should beobserved to verify normal operation. If abnormal performance is observed, additional measures may be necessary, such as reorienting or relocating the Liberator.
bOver the frequency range 150 kHz to 80 MHz, field strengths should be less than 3 V/m.
a

* This table is included as a standard requirement for equipment which has been tested to specific test levels and over specificfrquency ranges and been found compliant with regulations.
Liberator Technical Service Manual • PN 13350704 Rev M

9V Safety
Liberator

Table 6*
Recommended separation distances between portable and mobile
RF communications equipment and the Liberator
The Liberator is intended for use in an electromagnetic environment in which radiated RF disturbances are controlled. The customer
or the user of the Liberator can help prevent electromagnetic interference by maintaining a minimum distance between portable andmobile RF communications equipment (transmitters) and the Liberator as recommended below, according to the maximum output
power of the communications equipment.
Rated maximum output		Separation distance according to frequency of transmittermpower of transmitterW

150 kHz to 80 MHz

80 MHz and 800 MHz

800 MHz to 2,5 GHz

d=1.2√P

d=1.2 √P

d=2.3 √P

0,01

0.12 m0.12 m

0.23 m0,10.38 m0.38 m0.73 m

1

1.2 m

1.2 m

2.3 m

10

3.8 m

3.8 m

7.3 m

100
12 m
12 m
23 m
For transmitters rated at a maximum output power not listed above, the recommended separation distance (d) in meters (m) can be
estimated using the equation applicable to the frequency of the transmitter, where P is the maximum output power rating of the transmitter in watts (W) according to the transmitter manufacturer.
NOTE 1 at 80 MHz and 800 MHz, the separation distance for the higher frequency range applies.
NOTE 2 These guidelines may not apply in all situations. Electromagnetic propagation is affected by absorption and reflection fromstructures, objects and people.
* This table is included as a standard requirement for equipment which has been tested to specific test levels and over specific frquency
ranges and been found compliant with regulations.

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VI Theory of Operation
Liberator

FIGURE 3: Temperature vs. Saturation Pressure

Filling

There will be some oxygen vaporized during filling. This gas isdischarged through the vent valve. When the Liberator is full, liquid oxygen is expelled. Disconnecting the fill adapter from the
Liberator QDV and closing the Liberator vent valve terminates
the fill process.

-155

6.9, -157.4
-160

-165

LOX TEMPERATURE (°C)

The Liberator is filled by connecting a pre-purged transfer linewith a fill adapter from a larger liquid oxygen source to the
Liberator side fill or top fill QDV. The Liberator vent valve isthen opened. The pressure differential between the Liberator andsource tank forces liquid oxygen through the transfer line andinto the Liberator inner vessel.

-170

-175

1.4, -173.8-1800.0, -183.0-185

FIGURE 2: Filling
-190
0

1

2

3

4

5

6

7

8

SATURATION PRESSURE (BAR)

There are two conditions which can seriously affect the overall
efficiency and operation of the system:

Vent Valve

LiquidGas
Fill Connection
(QDV)

Gas

Saturation Pressure
The saturation point of a liquid is a steady-state condition where
the liquid has absorbed the maximum amount of heat possible.
A liquid can be at its saturation point at a number of differentpressures and temperatures, but each specific saturation pressure
has a corresponding saturation temperature and vice-versa (seeFigure 3). This means that the final temperature of your liquid
oxygen is dependent upon the pressure at which it is transferredfrom the storage system to the Liberator. For the purposes of thismanual, we will speak in terms of saturation pressure, since it iseasier to control than temperature. Treat saturation temperature
as a dependent variable of saturation pressure.

1. Saturation pressure of the liquid oxygen in the fill source issubstantially higher than the Liberator operating pressure(oversaturated).
2. Saturation pressure of the liquid oxygen in the fill source issubstantially lower than the Liberator operating pressure (undersaturated).
For example, when a Liberator is filled from a liquid source saturated at 6,9 bar (100 psig), larger transfer losses will occur. This isbecause the Liberator is designed to operate at 1,4 bar (20 psig),
and the liquid it is filled with is saturated at a much higher pressure and at its correspondingly higher temperature. It is necessary for this liquid to reach equilibrium at a lower pressure andtemperature before the relief valve will close and the Liberator
will operate properly.
In order to become saturated at 1,4 bar (20 psig), the liquid oxygen must release enough heat for its temperature to be lowered tothe temperature corresponding to a pressure of 1,4 bar (20 psig),
as shown in the graph. The temperature is lowered through boiling. All of the gas generated by this boiling is vented through therelief valve and/or primary relief valve and is lost.
If the saturation pressure of the liquid oxygen in the filling vessel is lower than the normal operating pressure of the Liberator,
oxygen vaporization within the dewar works to raise the systempressure to the required 1,4 bar (20 psig). This may require aslong as a day. The time required for saturation to 1,4 bar (20 psig)
depends on the initial liquid saturation pressure.

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VI Theory of Operation

WARNING: The vent valve orifice does not guarantee properly
saturated LOX. The filling source must be correctly saturated or
low/high saturation will occur in CAIRE reservoirs.

To minimize the effect of undersaturated liquid in the Liberator, afixed orifice has been installed in the outlet of the vent valve. Thisorifice regulates the back pressure in the unit during the fill process, resulting in improved saturation pressures in the Liberator.
Operation
If the flow control valve and vent valve are closed with LOX in theunit, then the pressure in the inner vessel will remain near the primary relief valve setting of 1,5-1,7 bar/21.8-24.2 psig.
In the Liberator, as in all vacuum-insulated cryogenic
contain-ers, some liquid (oxygen in this case) is always
evaporating into a gas. The rate of generation of this gas, withthe flow control valve closed, is called the normal evaporation
rate (NER). This gas is lost through the primary relief valve.

When the flow control valve is at any setting other than off, andthe economizer valve is open (presure over 1,4 bar (20 psig), see
Figure 4), gaseous oxygen is forced from the head space in the
inner vessel, through the economizer valve, to the breathing coil.
This process conserves or “economizes” liquid oxygen by withdrawing the head gas first, instead of allowing it to escape throughthe relief valve.
While flowing through the breathing coil, the cold gaseous oxygen is warmed to near-ambient temperature before being metered and dispensed by the flow control valve.
Whenever gas is removed from the space above the liquid oxygen (head space), the inner vessel internal pressure begins todrop slightly. When the pressure drops to 1,4 bar (20 psig), theeconomizer valve closes,(see Figure 5) forcing liquid oxygen up
the withdrawal tube and through the warming coil where it becomes gas.
The gas then flows through the bypass tee to the breathing coil,the flow control valve, and then the patient.
As the pressure in the container increases over 1,4 bar (20 psig),
the economizer valve opens, and the cycle repeats, maintaining
constant oxygen flow, at the selected flow rate, to the patient.

FIGURE 4:

FIGURE 5:

Operation between 1,4 Bar (20 PSI) and 1,7 Bar (24.2 PSI)

Operation between 1,2 Bar (18PSI) and 1,4 Bar (20 PSI)

Gas to Patient

Gas to Patient

Breathing
Coils

Liberator

WARNING: Low oxygen flow rates to the patient may result if the
Liberator is filled with undersaturated liquid oxygen.

Breathing
Coils

Economizer(Open)

Economizer(Closed)Warming
Coils

Gas*Note: The operation
detailed in bothFigures 4 and 5 areconsidered normal
operation.

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VI Theory of Operation
Liberator

Liquid Level Measurement

FIGURE 6: Liquid Level Meter Circuit

Liberators are equipped with a unique liquid level measurement
system. This system measures the level of liquid oxygen inside theunit with a capacitance probe and displays that liquid level on thelevel meter’s LEDs.
The liquid level probe consists of two concentric stainless steel
cylinders extending inside the inner vessel. As the liquid oxygen
level rises, the capacitance of this assembly goes up. The level
meter then displays the liquid level in the cylinder based on acalibration relating capacitance to fill level. The higher the liquid
level in the dewar, the more LEDs are activated, beginning at theleft most LED.

JST Connector

Electrical connection between the level meter and the probe ismade via a single conductor JST connector. This male plug is attached to its female counterpart extending from the probe, creating a watertight connection. A single ground wire is connectedfrom the meter to a male spade terminal on the mounting bracket.
The meter is powered by an internal battery offering battery
life of 5 years or more at 30 cycles per day. The meter has a low
battery (LOW BATT) indicator which signals the need for battery replacement. The meter battery is covered under a 2-year
limited warranty. If battery failure occurs within 2 years of the
Liberator shipment date, contact CAIRE, Inc. customer service
for a replacement meter. If the meter battery is no longer underwarranty, the CR2032 coin cell battery can be replaced (RP5).
Replacement batteries can be found at most hardware stores orthey can be ordered through CAIRE customer service.
The new level meter improves upon the previous meter by integrating all components within its casing, simplifying removal
and replacement (RP4). Even more importantly, there is a much
improved calibration procedure that requires no additional tools
and a range of error reporting codes which can be read directlyfrom the LEDs to report calibration errors. These can be foundin the calibration procedure (RP7).

NOTE: Tampering with meter battery housing will void thebattery’s 2-year warranty.

Liberator Technical Service Manual • PN 13350704 Rev M

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13

VII Unpacking and Setup
1. Inspect carton for shipping damage. Report any damage tofreight company before signing bill of lading.

Liberator

FIGURE 7: Flow Control Knob

Unpacking

2. Check description on carton against your order.
3. Unpack unit, including condensation bottle and bracket,
POI, FCV extension, and humidifier elbow kit.
4. Set aside packing materials in case unit must be returned to
the factory.
Setup
1. Install condensation bottle bracket by squeezing bracket
ends together and inserting into slot in handling ring
directly below FCV outlet.
2. Install condensation bottle on bracket located below shroud.
Remove cap from bottle. Put condensation hose inside bottle.
3. Install FCV extension by screwing it into the side of the
FCV to 45 N-cm (4 in-lb).

c. Remove flow rate decal number disc (Item 2).

4. Install humidifier elbow (if applicable) by screwing it into
the side of the FCV extension.

d. Remove locking pin (Item 65) from its storage position on
flow lock plate (Item 3) and place in underside of hole corresponding to maximum allowable flow rate.

5. Visually inspect the Liberator for damage from improper
handling. Note any dents in the container, cracks in the
shroud, missing or loose hardware, and bent quick
disconnect valves or humidifier adapters.

e. Replace flow lock plate (Item 3), number disc (Item 2) andknob. Tighten screws (Item 4) to 45–65 N-cm (4–6 in-lbs).
Verify flow lock is at correct position.

6. Check for smooth operation of the flow control selector,
making sure that a positive detent is felt at all settings. The
flow control knob should be secure and properly aligned.

FIGURE 8: Lock Plate Layout
Locking Pin Holder

7. Check the vent valve for smooth operation.

11. If desired, the flow control knob (Item 1) can be adjusted so
it will not exceed maximum prescribed flow rate.
a. Remove FCV knob by firmly grasping the knob and pulling away from the base unit.
b. Remove two Phillips head screws (Item 4) from flow lockplate (Item 3) and remove plate.

4

5

3
Screw Hole

6

1.5

10

3/4
1/2

Screw Hole81

9. Verify operation of the level meter by depressing the operatebutton. LEDs will light, displaying the level of liquid oxygen.
If the unit is empty, only the leftmost LED should light. If it
does not, or if other erroneous indications are given, refer tothe Troubleshooting Section (Section X).
10. Check all labels for damage and wipe away any dust on unit
with a clean, dry, lint-free cloth. Prior to transportation
with liquid oxygen, ensure that you affix the included
Hazard Warning Label or a suitable replacement.

2.5

2

8. If possible, connect a portable unit to the Liberator to checkfor smooth coupling, and to make sure the portable unit isin proper alignment with the Liberator when mated.

0
1/4

12

15LPM Stopper

CAUTION: Always ship, store, or transport a Liberator, empty or
full, in an upright position, properly secured to prevent damage.
DO NOT ROLL UNITS TO TRANSPORTWARNING: Ensure the locking pin, if used, is set to allow theprescribed flow of the patient upon setup.
Transport
Specifically designed roller bases are available for moving
Liberator short distances on smooth surfaces. Hand trucks canalso be utilized for Liberator transport.
Liberator Technical Service Manual • PN 13350704 Rev M

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VIII Operation

Filling
NOTE: The fill source should have the correct fitting (5/8” x 45°
male flare) to connect to transfer line.
WARNING: Filling must be performed in a well-ventilated area
to prevent development of an oxygen-enriched atmosphere.
WARNING: Wear insulated gloves and eye protection whenever working with liquid oxygen.
1. Fill Source Preparationa. Ensure the source contains a sufficient amount of liquid
oxygen to completely fill the reservoir.
b. Ensure the liquid oxygen in the fill source is saturated at
2,4-3,4 bar (35-50 psig).

d. Fully open liquid valve on fill source.
e. Purge transfer line for a minimum of 5 seconds ensuring
gas is safely piped away from operator:
i. Connect transfer hose fill adapter to a securely
mounted mating QDV.
-OR		 ii. If the transfer hose fill adapter is equipped with amale QDV, push the adapter poppet against an unpainted
stainless steel surface.
f. Wipe both reservoir and transfer line adapter fill connectors with lint free rag to remove residual moisture.
NOTE: Purge the transfer line any time fill source valve has beenclosed.
g. Using vent valve wrench, fully open reservoir vent valve.
h. Connect transfer line to reservoir to begin fill.
i. While filling, throttle the vent valve with the vent valve
wrench as needed to keep the reservoir pressure at the nominal fill pressure of 1,38 bar (20 psig). Monitor the pressure
by connecting a pressure gauge to the oxygen outlet andopen the FCV to 2LPM or greater.

NOTE: Proper saturation is critical when filling a CAIRE reservoir.
If the fill source is not properly saturated, the unit will not function correctly, resulting in inaccurate flow rates and excessive
boil off of liquid oxygen. This will cause portable units which arefilled off the reservoir to act in the same manner. Please refer tothe Saturation Principles section to learn more about the importance of proper saturation.

j. When liquid flows from the vent outlet, terminate the fill bydisconnecting the transfer line fill adapter from the reservoir
using the reservoir’s pop-off assembly.

2. Fill Procedurek. Close reservoir vent valve immediately after disconnecting
the transfer line from the reservoir.

a. Required Equipment:o Fill source as outlined above
o Liquid oxygen transfer lineo Appropriate transfer line fill adapter
o Appropriate vent valve wrencho Eye protectiono Pressure gaugeo Insulated gloves
NOTE: Ensure Compliance with All Local Regulations when
Filling LOX Reservoir Units.
b. Verify that the liquid level meter is operating properly.

Liberator

Liberator 20, 30, 37, 45 and 60 units may be moved about ortransported in a vehicle while full without damage; however, theyshould not be dropped or handled roughly in order to prevent
necktube damage.

If filling pressure is not monitored, it must be ensured that
the Liberator has reached its correct operating pressure
prior to patient use, or incorrect flow rates may result.

Caution: Do not allow excessive venting of liquid oxygen throughthe vent valve. Prolonged exposure may freeze the vent valve inthe open position.
l. Replace protective cover on the QDV adapter. Close theliquid valve on the fill source and properly store thetransfer line and fill adapter.
m. Verify that the liquid level meter indicates full.
NOTE: The liquid level indicating system is only accurate after
the vent valve is closed, and the oxygen has stabilized for five minutes.

NOTE: If liquid level meter operates improperly, refer toTroubleshooting section of the corresponding technical manual.
c. Connect transfer line to fill source. Connect proper transfer
line adapter to transfer line.

Liberator Technical Service Manual • PN 13350704 Rev M

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VIII Operation
As noted in the Theory of Operation (Section 6), Generation 4
Liberators are equipped with new liquid level meters. In order toobtain a liquid level reading, the technician or end-user should depress the green operate button on the face of the meter (note that the
button has been moved onto the meter from its previous position).
This will cause the LEDs to quickly flash from right to left aroundthe meter’s perimeter to indicate button activation. The LEDs willthen light from the left to the right, signifying the liquid level in thecylinder (1 LED for empty, 8 for full). If you feel the meter is giving
incorrect measurements, reference RP7 to calibrate the meter.

Cleaning and Disinfection
To insure proper functioning and end-user safety, all Liberator
units should be cleaned whenever dirt or grime is visually apparant.
The unit should be disenfected according to any applicable local
regulations or the home healthcare distributor’s own decontamination schedule.
Preparation
Prior to cleaning or disinfection, the unit should be completely
purged of LOX. The technician should wear appropriate safety gear
and prepare mild solutions of glass cleaner and disinfectant respectively. If at any time either solution becomes visibly dirty or cloudy,
it should be switched out for fresh solution.

Cleaning

Table 1 shows actual material content of the Liberator base unit toassist the home healthcare distributor in establishing its own disinfection protocol.
Table 2 lists a selection of common disinfectant chemicals and theircompatibility with Liberator base units.

Liberator

Liquid Level Measurement

TABLE 1: Liberator Material Content
Part

Material

ShroudPolycarbonate

Breathing Coil

T3003 Aluminum

Vaporizer Coil

T3003 Aluminum

Dewar

Stainless Steel

ValvesT6061 Aluminum

TABLE 2: Common Disinfectant Chemicals
Disinfectant Agent

Compatible with Generation 4
Liberators

Aldehyde

Yes

Quanternary Ammonium
CompoundSauerstoffabspalter
Alcohol
Amine Derivatives
Phenol
pH: Basic (alkaline) Cleaners
Ether/Ester based products

Yes
No*Yes - Ethanol based cleaner(only when all O2 has been
purged)
Yes
Yes
Yes
No

1. Inspect through air holes in shroud to see if any debris has accumulated beneath shroud. If it has, remove debris using long
tongs or tweezers.
2. Wipe off the exterior of the unit with the cleaning solution using a lint-free cloth. The cloth should be damp but not dripping. Be as thorough as possible.
3. Discard the cleaning cloth.
4. Wipe off excess cleaning solution and dry thoroughly with alint-free cloth. Discard the cloth.

Product Disposal
At the end of the unit’s life, all Liberator units must be re-turned
to a recycling facility in compliance with the Waste Electrical andElectronic Equipment Directive (WEEE), or other applicable
codes and regulations.

Disinfection
Disinfection should be performed in accordance with the homehealthcare provider’s own validated procedures and/or in accordance with local regulations.
NOTE: Only use disinfectants or cleaning agents approved foruse with this equipment by CAIRE such as Sporicidin,
Hydroklean, or others as specified by CAIRE.
Liberator Technical Service Manual • PN 13350704 Rev M

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IX Maintenance (Schedule A, 30-Month)

A. Introduction
Routine maintenance is a series of steps used to assure that equipment is functioning properly.
1. If a unit fails a given test, one of two things may be done:
a. Refer to the Troubleshooting section of the corresponding
technical manual.
-orb. Return the unit to CAIRE, Inc. for repair.
2. Schedule – Maximum of 30 months between routine
maintenance testing. Unit should be tested whenever a
problem is suspected.

c. Perform PRV test (RP13).
d. Perform SRV test (RP13).

Liberator

There are two schedules for routine maintenance which the homehealth care distributor may follow. These schedules allow the distributor maximum flexibility while assuring that equipment is
operating properly.The healthcare distributor may follow either
Schedule A or Schedule B, or a combination of the two schedules.
CAIRE, Inc. recommends returning the unit to a CAIRE service
facility every 10 years for vacuum check and re-evacuation
if necessary.
Schedule A –30 Monthe. Pressure Retention Test (RP15).
f. Replace shroud (RP2).
g. Liquid Contents/Level Indicator Test (RP6).
h. Flow Rate test (RP25).
3. Check Efficiency of Unit:
a. Inspect unit for cold or sweaty condition and for excessive
venting from relief valve (some venting is normal).
b. If the dewar bottle is cold and sweating, and/or there isexcessive venting from the relief valve, an NER test should be
performed (RP32).
4. Prepare for Use:a. Empty contents (RP23).

B. Procedure
Follow the steps in order listed. If the unit fails any step, refer toTroubleshooting section of the corresponding technical manual.
NOTE: See the Troubleshooting and Repair section of the corresponding technical manual on the detailed procedures for thetests mentioned below.

b. Clean and/or disinfect outside of unit following instructions
set forth in the Operation section of the corresponding
technical manual.

1. Visual Inspection:
a. Remove any LOX prior to maintenance (RP23).
b. Look for damaged or missing parts.
c. Verify the meter reads empty. For reservoirs equippedwith electronic level gauges, verify the low battery LED is
not lit and no error codes appear on the meter.
2. Component Test:
a. Remove shroud (RP2).
b. Perform Leak Test (RP16)

Liberator Technical Service Manual • PN 13350704 Rev M

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IX Maintenance (Schedule B, Continuous)e.

A. Introduction

f. If LOX is still present in the unit, inspect for heavy frost
or condensation on the exterior of the unit, which would indicate poor vacuum.

Continuous maintenance is a set of tests and inspections done periodically to ensure equipment is functioning properly. It can be
performed by drivers or other personnel while the equipment isin service.

g. Visible dirt or contaminants inside and outside of theupper shroud, as well as inside and outside of the condensate
collector.

1. If a unit fails a given test, it should be taken out of service
and sent to the Repair Center/Department for further inspection.
2. Schedule – Scheduled intervals should be determined by theequipment service provider.
B.

Pre Fill Procedure

1. Visually inspect for:

Cryogenic reservoir damage (dents, dings)

h. Vent valve functionality (all parts are present and thevalve functions as intended)C.

Post-Fill Procedure

1. Visually verify:a.

QDV poppet is closed and not leaking
Vent valve is not leaking

a.

Broken shrouds or shroud componentsb.

b.

QDV deformationc. No heavy frost or condensation is present on the exteriorof the vessel of the reservoir

NOTE: When inspecting a Side-Fill QDV, be sure to checkthe lip seal for damage.
c.

Level indicator functionalityd.

Presence of all required labels

Liberator

Schedule B – Continuousd.

Liquid level indicator is showing full after filling

Liberator Technical Service Manual • PN 13350704 Rev M

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X Troubleshooting
A.
B.
C.

D.

Introduction-------------------------------------------------------------------------- 19
Troubleshooting Charts- -------------------------------------------------------- 20–23
Repair Procedures
General ---------------------------------------------------------------- 24
RP1
Shroud Assembly RR ------------------------------------------------- 24
RP2
Condensation Bottle Bracket RR ------------------------------------- 24
RP3
Liquid Level Meter RR ------------------------------------------------ 24
RP4
Liquid Level Meter Battery RR --------------------------------------- 24
RP5
Liquid Level Meter Calibration -------------------------------------- 25
RP6
G4 Meter Troubleshooting ------------------------------------------- 26
RP7
Manifold Capacitance Test ------------------------------------------- 28
RP8
Manifold Assembly RR ----------------------------------------------- 28
RP9ResolderFeed-thru Wire --------------------------------------------- 29
RP10
Manifold Harness Assembly RR ------------------------------------- 29
RP11
Clean/Dry Probe & Dewar -------------------------------------------- 30
RP12
Relief Valve Test ------------------------------------------------------ 30
RP13
ReliefValve RR ------------------------------------------------------- 30
RP14
Pressure Retention Test ---------------------------------------------- 31
RP15
Plumbing Leak Test -------------------------------------------------- 31
RP16
Warming and Breathing Coil Assembly RR ------------------------ 32
RP17
Vent
Valve RR -------------------------------------------------------- 32
RP18
Twist Lock QDV Lip Seal RR ---------------------------------------- 32
RP19
Twist Lock QDV RR -------------------------------------------------- 33
RP20
Push-on QDV RR ----------------------------------------------------- 33
RP21
Push-on Portable Pop-Off Assembly--------------------------------- 33
RP22
Empty Unit ------------------------------------------------------------ 34
RP23
Warm Unit ------------------------------------------------------------ 34
RP24
Flow Rate Test--------------------------------------------------------- 35
RP25
Operating Pressure Test ---------------------------------------------- 35
RP26
Flow Meter Verification ---------------------------------------------- 35
RP27
Economizer Regulator RR ------------------------------------------- 37
RP28
Economizer Regulator Test ------------------------------------------ 37
RP29
Flow
Control Valve (FCV) RR -------------------------------------- 37
RP30
Dewar RR ------------------------------------------------------------- 37
RP31
Normal Evaporation Rate (NER) Test ------------------------------ 38
RP32
Calculating Liquid and Gaseous Oxygen Capacity ----------------- 38
RP33
Service Tools / Fixtures / Equipment / Supplies ---------------------------------- 39

Liberator

Table of Contents

Introduction
1. These procedures are designed to be performed only by qualified personnel with proper equipment.
2. Any failure during routine maintenance checks will refer you to this section. See troubleshooting chart for appropriate
procedure.
Liberator Technical Service Manual • PN 13350704 Rev M

19

XII Troubleshooting Charts
1)

Unable to start fillor excessively
long fill times

Probable Cause

Corrective Actiona)Transfer line not engaged fully on
Reservoir QDVMake sure the QDV on the transfer line and reservoir are properly aligned andensure that a downward force is being applied to the transfer line assembly.

b)

Low source pressure

Verify that pressure from the source is within the 35-50 psi range to fill thereservoir.

c)Vent valve not open or is blocked

Ensure that the vent valve is able to be turned to the fully open position.

d)Source tank is either under orover-saturated

Allow LOX to saturate to proper pressure.

e)Fill connector not opening
properly

Check fill connector and cartridge assembly for damage; make sure fillconnectors fully engage.

f)

Vent valve is obstructed

Inspect the valve for blockages and verify that flow passes through during a fill.
Clean by blowing out with compressed gas or replace parts if necessary.

g)Leak in the system

Check the reservoir for leaks (RP16) and repair if needed.

2)

Liquid leaks fromthe coupled QDVs
during the filla)Worn or damaged lip seal

Replace the QDV lip seal (RP19)

3)

Unableto disconnect
the transfer linefrom the reservoir
after a filla)Pop-off assembly not being
utilized (Does not apply to
Liberator 10)

Ensure that the pop-off assembly on t he reservoir is being used. Do not use
force to separate the QDVs.

b)

QDVs are frozen together

Leave the units coupled with the vent valve closed and let them sit until theywarm up enough to disconnect. Always ensure that male and female QDV’s arecleaned and dried prior to each fill.

a)

Ice crystal preventing the QDVfrom closing properly.

Engage and disengage the transfer line onto the reservoir several times todislodge the ice crystal. Always be sure that the male and female QDVs are
wiped clean and dry before filling.

b)

Dirty or damaged QDV p oppet

Replace the QDV cartridge (RP20) or the entire QDV assembly (RP21)a)Saturation pressure too high.

Inspect the saturation pressure of the reservoir used for filling. Allow at least
30 minutes at no flow for the portable to saturate properly.

b)Relief valve frozen open

Allow the portable to warm and thaw. Attempt to re-fill the portable.

c)Faulty relief valve

Test the relief valve (RP13) and replace if necessary (RP14)d)Partial or complete loss of vacuum Conduct the NER test (RP32) and return the unit to CAIRE, Inc. if necessary.

a)

Reservoir is empty

Check the contents indicator/level gauge and fill the reservoir if needed.

b)

Flow control valve turned off

Ensure the flow control knob is not in the off (“0”) position.

c)Ensure proper nasal cannula functionality and positioningf)Nasal cannula kinked or
disconnected
Leak in the systemg)

Relief valve is open

Ensure that there is no venting from the relief valves. If there is refer to thecorrective actions for “Excessive venting from relief valves (hissing sound)”.

h)

Vent valve is open

Ensure that the vent valve is fully closed.

i)

FCV inlet filter is obstructed

Clean or replace (RP30) the filter screen.

j)k)

Blockage in the liquid withdrawal Check warming coils and withdrawal tubes for blockages. Replace if necessary.
circuitReplace the FCV (RP30)
FCV Faultya)Nasal cannula kinked or leaking

4)

5)

6)

7)

Liquid leaks fromthe QDV poppet
after f illing
Excessive venting
from relief valves(hissing sound)No flow at oxygen
outletLow flow at oxygen
outlet on all LPM
settings

Liberator

Symptom

Perform a leak check on the plumbing (RP16). Repair leaks as necessary.

Inspect the functionality of the nasal cannula.

b) Saturation pressure is too low

Inspect the saturation pressure of the reservoir. Allow at least 30 minutes at noflow for the reservoir to saturate properly.

c) Leak in the system

Perform a leak check on the plumbing (RP16). Repair leaks as necessary.

Liberator Technical Service Manual • PN 13350704 Rev M

720

XI Troubleshooting Charts
7)(Cont.)

8)

9)

10)

11)

Low flow at oxygen
outlet on all LPM
settings (cont.)

Increased NER

Probable Caused)Clean or replace (RPxx) the filter screen.

e)Economizer valve faulty

Test the economizer (RP28) and replace (RP29) if necessary.

f)Blockage in the liquid withdrawal Check the warming coils and withdrawal tubes as well as the flo w restrictor forblockages. Replace if necessary.
circuit or the flow restrictorg)

FCV faulty

Replace the FCV (RP30)

a)Saturation Pressure is too
highInspect the saturation pressure of the reservoir. Allow at least 30 minutes at noflow for the reservoir to saturate properly.

b) Leak in the system

Perform a leak check on the plumbing (RP16). Repair leaks as necessary.

c)Relief valve open

Ensure that there is no venting from the relief valves. If there is refer to thecorrective actions for “Excessive venting from relief valves (hissing sound)”.

d)Partial or complete loss of
vacuumConduct the NER test (RP32) and return the unit to CAIRE, Inc. if necessary.

a)
Excessive Frost:
NOTE: Minimal
frost on the shroud
and on theplumbing is normal.
b)This symptom
applies to frost thatc)is much greaterthan what isnormally observed.
d)

Frost is acceptable

Some frost on the shroud and on the plumbing is acceptable, especially at highflow rates during continuous use. This is due to the evaporation of LOX to gas
and the temperature difference between the LOX and room temperature.

High humidity level

High humidity levels can increase frost accumulation.

Saturation pressure is too h igh

Inspect the saturation pressure of the reservoir. Allowat least 30 minutes at no flow for thereservoir to saturate properly.

Leak in the system

Perform a leak check on the plumbing (RP16). Repair leaks as necessary.

e)Relief valve open

Ensure that there is no venting from the relief valves. If there is refer to thecorrective actionsfor “Excessive venting from relief valves (hissing sound)”f)Partial or complete loss of
vacuumConduct the NER test (RP32) and return the unit to CAIRE, Inc. if necessary.

a)Saturation pressure isunacceptable

Inspect the saturation pressure of the reservoir used for filling. Allow atleast 30 minutes at no flow for the portable to saturate properly.

b)Vent valve is not completely
close

Close vent valve. Leak check vent valve outlet and stem. Replace or repair as
needed.

c)Leak in the system

Perform a leak check on the plumbing (RP16). Repair leaks as necessary.

d)Economizer valve faulty

Test the economizer (RP28) and replace (RP29) if necessary.

e)Primary releif valve faulty

Test the primary relief valve (RP13) and replace (RP14) if necessarya)Saturation pressure is too highInspect the saturation pressure of the reservoir. Allow at least 30
minutes at no flow for the reservoir to saturate properly.

b)Primary relief valve set toohigh or relief valve
operating improperly.
Economizer valve stuck inclosed state

Perform relief valve test. Replace as needed.

d)Partial or complete loss of
vacuumConduct the NER test (RP32) and return the unit to CAIRE, Inc. if necessary.

a)Battery voltage too low to
operate contents indicator

Replace battery as needed (RP5) then calibrate the meter following RP6)b)

Sensor wires not connected
properly, pinched orotherwise damaged
Contents indicator not
calibrated properly

Visually inspect the meter harness assembly from the meter to the point
wheret he sensor wire enters the reservoir manifold. Replace as necessary.

Ice crystal in reservoir causing
incorrect or empty level
reading
Meter malfunctioning/damagedEmpty and warm the reservoir following (RP23, RP24) to melt and evaporate
moisture from inside the reservoir.

Unit will not
maintain
acceptable systempressureHigh Pressure atReservoir oxygen
outletc)

12)Corrective Action

Flow control valve inlet
filter screen dirty

Contents indicatorreads incorrectly

c)
d)
e)

Liberator

Symptom

Perform Economizer test. Replace as needed.

Calibrate the meter as needed following (RP6).

Inspect for physical damage. Replace meter as necessary then recalibrate themeter follow-ing (RP6)

Liberator Technical Service Manual • PN 13350704 Rev M

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XI Troubleshooting Charts
Liberator

8

Liberator Technical Service Manual • PN 13350704 Rev M

22

XI Troubleshooting Charts
Liberator

To use the Troubleshooting Chart:• Start at the upper left corner.
• The top line shows the steps of routine maintenance.
• Unless otherwise noted by the arrows, the flow through the chart is down or to the right.
Liberator Technical Service Manual • PN 13350704 Rev M

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XII Repair Procedures
RP2 – Shroud Assembly RR (Figure 9)

The following procedures have been carefully prepared to allow
proper removal and replacement of defective components andshould be used in conjunction with the Troubleshooting Chart andthe tests in this section. All repair procedures and specificationsin this manual supersede those in previous revisions of themanual and are valid for all G4 Liberators.

a. Remove humidifier adapter (Item 26) and FCV extension (Item25) from FCV (Item 24).

WARNING: Make sure the unit is empty and vent valve is open
before replacing any component, except shroud assembly components or Lip Seals.

Liberator

RP1 – Generalb. Remove shroud mounting screw (Item 13).
c. Remove shroud (Item 7) by lifting up and moving sideways toclear the QDV on side fill models, or by lifting straight up top
fill models.
d. To replace shroud assembly, reverse above procedure. Torque
FCV Extension (Item 25) onto FCV to 45 N-m (4 in-lb).
RP3 – Condensation Bottle Bracket RR

WARNING: The technician’s hands, tools, and clothing should befree of all oils and greases.
WARNING: Parts that are welded in place must not be replacedin the field. Should these parts fail, return complete assembly or
sub-assembly to factory for repair. DO NOT use solder or silver
solder to repair broken welds.
WARNING: The manufacturer of fluorolubricant warns users not
to allow fluorolubricant to contaminate tobacco products. Wash
fluorolubricant from hands before smoking.
WARNING: Do not use glue type thread locking compounds orunapproved sealants on any repairs.
CAUTION: When replacing components, make sure the new part isoriented exactly the same as the original part prior to installation.
CAUTION: Some components require a specific amount of torquewhen assembling. Follow torque requirements where specified.

NOTE: All replacement parts must be factory approved, cleaned
for oxygen service, and stored in sealed plastic bags. The repair
area must be clean and separate from other areas. Room air should
be filtered, and free from dust, soot, and other contaminants.
NOTE: When replacing components with pipe threads, use PTFE
tape thread sealant. Apply two rounds of PTFE tape to threads
near end of component, avoiding first thread.
NOTE: When assembling new compression fittings, tighten 1/8”,
1/4” and 1/2” nuts eight flats past finger tight and 3/16” nuts fiveflats past finger tight. When reassembling previously used compression fittings, tighten nuts one to two flats past finger tight.

a. Remove condensate drain tube (Item 58) from bottle (Item56) and remove bottle from bracket (Item 57).
b. Remove condensate bottle bracket (Item 57) by squeezing legs
together and pulling straight down.
c. To replace bracket, reverse above procedure.
RP4 – Liquid Level Meter RR
a. Remove shroud (See RP2).
b. Remove two screws attaching liquid level meter to the bracket,
being careful not to pull on the meter wires.
c. Detach JST connector (red signal wire) and spade connector(black ground wire).
d. To replace meter, screw new meter into place using the top set ofholes on the meter and reattach wires.
e. Calibrate meter per RP6.
RP5 – Liquid Level Meter Battery RR
NOTE: Tampering with meter battery housing will void the battery’s 2-year warranty.
If meter battery failure occures while the battery is under warranty, contact customer service to obtain a replacement meter.
If meter battery is no longer under warranty, the CR2032 coin cellbattery may be replaced following the steps below.
a. Remove liquid level meter (See RP4).
b. Using a pair of pliers, grasp the battery cover on the back of themeter. Twist counter-clockwise and pull the cover away from themeter, removing the battery cover.
c. Slide the tip of a flathead jeweler’s screwdriver beside the battery
and carefully pry out the battery.
Liberator Technical Service Manual • PN 13350704 Rev M

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XII Repair Procedurese. Apply a thin coating of fluorolubricant to the o-ring.
f. Replace battery cover by pushing it into the back of the level
meter’s case, ensuring the o-ring seals evenly and without kinks
to restore the air-tight seal.
FIGURE 9: Shroud Assemblyb. Within 3 sec, press and hold the operate button. LED 1 andLED 8 will begin alternately flashing to signify that calibration mode has been entered. If an error occurs, the calibration
value will not be saved.

Liberator

d. Insert new battery with the positive terminal facing up.

c. Proceed to next step within 45 seconds.
Calibrate Empty Capacitancea. Press and hold calibrate button for 3 sec to record empty
ca-pacitance reading (LED 1 will flash for 3 sec).
b. LED 1 will flash to signify successful calibration. If an error
occurs, certain LEDs will flash, signifying a specific error
code and the calibration value will not be saved. (SeeTable 6 for a list of error codes.)Calibrate Full Capacitance

RP6 – Liquid Level Meter Calibration (Figure 10)

There are two full capacitance procedures available. Procedure 1
is quite accurate and quicker to perform since it does not require
you to fill the dewar. Procedure 2 is even more accurate, but requires the dewar be vent-full with LOX.

WARNING: You must first calibrate the empty side, and then calibrate the full side.

NOTE: Please use only one of the following calibration methods.

Calibration is required to ensure accurate meter readings andshould be done whenever an error in level readings is suspectedor when the meter has been replaced. If a calibration procedure isunsuccessful, the calibration value will not be saved and an error
code will be displayed on the LEDs (See Table 4). To calibrate,first enter calibration mode before performing either full or empty
calibration.

TABLE 4: Capacitance Span LED Settings

NOTE: In order to obtain an accurate calibration, you must calibrate both empty and full capacitance. For the full capacitancepart of the calibration, you can choose either of the two procedures.
FIGURE 10: Liquid Level Meter
LED 8

LED 1

Model
Liberator 20

LED Setting
LED 2

Liberator 30

LED 3

Liberator 37
Liberator 45
Liberator 60

LED 3
LED 7
LED 6

To start either procedure, calibration mode must first beentered. There is no need to per-form both procedures for any
given calibration.
Procedure 1: Capacitance Simulated Full Method
a. Press the operate button 3 times within a 5 sec period of entering calibration mode. One of the LEDs will light continuously.
b. Press the calibrate button until the correct LED is continuously lit (See Table 4).

Calibrate Button(Hidden)Operate Buttonc. Press the operate button to save the calibration. If an error
occurs, the calibration value will not be saved.

Enter Calibration Mode

Procedure 2: Fill Method

a. Press and hold the hidden calibrate button. While still holding, continue to step B.

a. Enter calibration mode on a vent full unit with properly saturated LOX. If unit has just been filled, allow it to stabilize
before continuing.

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25

XII Repair Procedures
Liberatorb. Press and hold operate button for 3 sec. LED 8 will flash as themeter stores calibration value. If successful LED 8 will flash
again and calibration mode will exit. If an error occurs, thecalibration value will not be saved.
See Table 5 for typical LED meter reading versus unit weight.
TABLE 5: Unit Weight (kg) vs. Meter Reading
Model

20

30

37

45

60

LED

Min Max Min Max Min Max Min Max Min Max

1

17,6 20,6 22,0 24,7 22,7 27,9 24,9 31,3 34,2 38,1

2

20,6 23,5 24,7 28,9 27,9 33,1 31,3 37,6 38,1 46,3

3

23,5 26,5 28,9 33,2 33,1 38,3 37,6 44,0 46,3 54,4

4

26,5 29,5 33,2 37,4 38,3 43,6 44,0 50,3 54,4 62,6

5

29,5 32,4 37,4 41,7 43,6 48,8 50,3 56,7 62,6 70,8

6

32,4 35,4 41,7 45,9 48,8 54,0 56,7 63,0 70,8 79,0

7

35,4 38,3 45,9 50,2 54,0 59,2 63,0 69,4 79,0 87,1

8

38,3 41,67 50,2 55,94 59,2 63,48 69,4 74,9 87,1 100,1

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XIII Repair Procedures
The table below identifies the error codes that one is likely to comeacross.

LED 8

LED 1

Liberator

FIGURE 11: Calibration Errors

RP 7 – G4 Meter Error Codes (Figure 11)

Calibrate Button(Hidden)Operate Button
TABLE 6: Calibration Errors
LEDs

Name

Reason

Notes

Solution

2,3

Low Cap

Empty capacitance less than
100 PF

When calibrating empty

Check for loose connections
and recalibrate

6,7

High Cap

Empty capacitance greaterthan 300 PF

When calibrating empty

Remove moisture and debris
from probe

1,4

Low Span

Span less than 30 PF

When calibrating full

Empty unit and recalibrate

5,8High Span

Span greater than 80 PF

When calibrating full

Empty unit and recalibrate

1,3,5,7Range

The new full cap value is lessthan empty cap value

When calibrating full

Empty unit and recalibrate

TABLE 7: Operation Errors
LEDs

Name

Reason

Notes

Solution

2,4,6High Cap

Reading is 120 PF above calibrated
full value

Moisture/
Debris on probe

Remove moisture and debris
from probe and recalibrate

Low Batt, 2,4,6

Bad CalAllow span cal setting to time out
w/o pressing green button

New meter revision fixed

Recalibrate

1,3,5,7

Low Cap

Cap reading is 5 PF or greater lessthan calibrated empty value

Moisture in harness; added withnew meter rev (on alltelemetry meters)

Completely dry harness
assembly and recalibrate

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XII Repair Procedures
b. Capacitance Test:
1. Remove shroud assembly (See RP2).
Ground

2. Disconnect the wires leading from the manifold harness assembly to the level meter by disconnecting the JST connector, which is zip-tied to the bracket.

Liberator

FIGURE 12: Manifold Capacitance Test Setup

3. Connect JST connector on capacitance meter adapter tomanifold harness assembly (Item 29).
4. Connect alligator clip to manifold bracket.
5. Read manifold capacitance and compare to the acceptable
ranges found in Table 8. If it does not meet specifications, callTechnical Support.
TABLE 8: Manifold Capacitance Specifications
Model

Low Limit (pF)High Limit (pF)

Liberator 20

125

160

Liberator 30

125

170

Liberator 37

130

170

Liberator 45

140

180

Liberator 60

140

180

RP9 – Manifold Assembly RR (Figure 13 )a. Remove shroud assembly (See RP 2).
b. Disconnect compression fittings on the sides of the economizer
valve (Item 35).
c. Disconnect compression fitting from liquid withdrawal port
(Item D) being careful not to kink vaporizer coil or internal
PTFE tube.
d. Disconnect compression fitting (Item 34) from FCV (Item 24).
NOTE: Make sure unit is empty and at room temperature before
testing.

e. If desired follow RP17 to remove coils from the top of the
Liberator in order to make manifold removal easier.

WARNING: Before removing manifold assembly, Liberator must be
empty, warm and vent valve open.

f. Remove the three bolts (Item 31) that run through the FCV
bracket (Item 39) and through the manifold plate into the topof the dewar.

RP8 – Manifold Capacitance Test (Figure 12)
a. Capacitance Meter Set-Up:
1. Connect capacitance meter adapter to capacitance meter according to Figure 12.
2. Turn on capacitance meter and select 200 pF range.
3. Move zero adjustment on the front of the meter until the display reads zero.

g. Remove two remaining manifold mounting bolts (Item 31, notvisible in Figure 12), while holding manifold in place.
h. Lift manifold assembly straight up to remove.
i. Place dewar cap on dewar opening.
j. To replace manifold assembly, reverse above procedure. Applysmall amount of fluorolubricant to O-ring (Item 50) before assembly. Torque manifold mounting screws (Item 31) to 10–11
N-m (90-100 in-lbs) using cross-tightening method.

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XII Repair Proceduresa Remove manifold assembly (See RP9).

FIGURE 13: Manifold Assemblyb. Strip approximately 1/8” of insulation from feed-thru wire (ItemA) if necessary.

Liberator

RP10 – Resolder Feed-thru Wire (Figure 14)

c. Remove strain relief material holding the signal wire against thecapacitance probe.
d. Apply small amount of Stay-Clean flux to tinned area of probe(Item B) using a cotton swab.
e. Resolder feed-thru wire (Item A) to tinned area of probe (Item
B). Add small amount of lead-free solid wire solder if necessary.
f. Clean flux residue with distilled water and cotton swab. Dry
thoroughly.
g. Replace manifold following listed procedure (RP9).
RP11 – Manifold Harness Assembly RR (Figure 13)
a. Remove manifold assembly (See RP9).

FIGURE 14: Feed-thru Wireb. Remove strain relief material holding signal wire against the capacitance probe.
c. Unsolder feed-thru wire (Item A) from probe (Item B).
d. Loosen feed-thru nut (Item C) and remove harness.
e. To replace manifold harness, reverse above procedure. Tighten
feed-thru nut (Item C) 1 to 2 flats past finger tight.
f. Solder feed-thru wire (Item A) following resolder procedure (See
RP10). Replace manifold assembly (See RP9).
RP12 – Clean/Dry Probe and Dewar
Procedure 1:
a. Empty dewar per RP23.
b. Warm dewar per RP24.
c. If all moisture is not removed, continue with Procedure 2.
Procedure 2:
a. Remove manifold assembly (See RP9).
b. Blow off probe assembly with clean, dry nitrogen gas.
c. Blow out inside of dewar with clean, dry nitrogen gas
until inside is clean and dry.
d. Replace manifold assembly (See RP9).

CAUTION: Be careful not to bend or damage manifold assemblyor dewar neck tube.
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XII Repair Procedures
RP13 – Relief Valve Test (Figure 15)
NOTE: Liberator should be empty and warm before testing.

26

A

24
B

15

62

b. Assemble pressure gauge (Item A) and adapter (Item B) (usePTFE tape).
c. Connect gauge assembly to humidifier adapter (Item 26) on FCV
outlet. Open FCV (Item 24) to 6 LPM setting.

28

35

a. Remove shroud (See RP2).

Liberator

FIGURE 15: Relief Valve Test Set-up

d. Assemble oxygen regulator and pneumatic hose (Item C) with
DISS fittings and male pneumatic test adapter (Item D). Connect
assembly to oxygen gas source.

De. Connect male pneumatic test adapter (Item D) to Liberator
QDV (Item 15).
f. Slowly begin increasing pressure to between 1,5-1,7 bar/21.8-24.2
psig. PRV (Item 62) should begin venting (audible noise will beheard or bubbling will be seen if leak testing).

C

g. Slowly begin decreasing the pressure until the PRV (Item 62)
closes, meaning the audible noise is no longer heard or the bubbling is no longer seen if leak testing. The pressure at which the
PRV closes should be greater than 1,4 bar/20.5 psig.
h. Hold PRV (Item 62) closed and increase pressure to 1,9-2,3 bar(27-33 psig). SRV (Item 28) should open (audible venting and/or bubbling of leak test solution).

Design before April 2020

i. Decrease pressure to 1,3 bar (19 psig). Test relief valve with leaktest solution. A minimal amount of leakage (bubbling) is acceptable. If leakage is questionable, run pressure retention test beforechanging relief valve (RP15).

26
A

24
B

WARNING: Liberator must be empty and vented before starting
procedure.
Primary (Figure 16)
a. Remove shroud (See RP2).

35
62

RP14 –Relief Valve RR

15

D

28

C

b. Unscrew PRV (Item 62) from the economizer regulator(Item 35)c. To replace PRV (Item 62), reverse above procedure. Tighten the
RV approximately 10–20 degrees clockwise after the PRV bodycontacts the economizer regulator (minimum of 225-339 N-cm
[20-30 in-lbs]).
Secondary (Figure 17)
a. Remove shroud (See RP2).
b. Unscrew SRV (Item 28) from FCV (Item 24) or from heeconomizer regulator (Item 35).
c. To replace SRV (Item 28), reverse above procedure. Tigthen the
SRV approximately 10–20 degrees clockwise after the SRV
body contacts the economizer regulator (minimum of 339-418
N-cm [30-37 in-lbs]).

Design after April 2020
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XII Repair Procedures
35
62

e. Connect male pneumatic test adapter (Item D) to
Liberator QDV (Item 15).
NOTE: PRV and SRV may leak slowly. Repair all other leaks firstand retest for pressure retention before changing relief valves.

28

f. Leak test all connections, joints, and valves with leak test
solu-tion.

FIGURE 17: Secondary Relief Valve
35
62
28

28

24
Design Before April 2020 - left F16. and F17

d. Assemble oxygen regulator, pneumatic hose (Item C) with
DISS fittings and male pneumatic test adapter (Item D).
Connect as-sembly to oxygen gas source.

Liberator

FIGURE 16: Primary Relief Valve

Design after April 2020 - right F16. and F17

RP15 – Pressure Retention Test (Figure 18)

g. Close FCV (Item 24) by turning to Off position. Remove
pressure gauge assembly from humidifier adapter (Item26).
h. Disconnect pneumatic adapter (Item D) from QDV(Item 15).
i. Leak test QDV poppet and FCV outlet.
j. Repair all leaks by following appropriate repair
procedures.

WARNING: Leak Detector solution should be completely
cleaned from the QDV assembly using dry nitrogen after
testing.
FIGURE 18: Plumbing Tests Set-up

a. Assemble pressure gauge (Item A) and adapter assembly (ItemB) (use PTFE tape).

26

b. Connect gauge assembly to humidifier adapter (Item 26) on FCV
outlet. Open FCV (Item 24) to 6 LPM setting.
c. Assemble oxygen regulator, pneumatic hose (Item C) with DISS
fittings and male pneumatic test adapter (Item D). Connect assembly to oxygen gas source.
d. Connect male pneumatic test adapter (Item D) to Liberator
QDV (Item 15).
e. Increase pressure to 1,4 bar (20 psig).
f. Disconnect male pneumatic test adapter (Item D) from QDV(Item 15).

A

24

62

B

D
15

g. Turn FCV valve (Item 24) to Off setting.
h. Allow unit to sit undisturbed for 60 minutes.
i. Turn FCV valve (Item 24) to 6 LPM setting.

C

j. If pressure gauge (Item A) indicates less than 1,24 bar (18 psig),
unit fails test.
NOTE: Liberator should be empty and warm before testing.
RP16 – Plumbing Leak Test (Figure 18)
a. Remove shroud (See RP2).
b. Assemble pressure gauge (Item A) and adapter assembly (Item(use PTFE tape).
c. Connect gauge assembly to humidifier adapter (Item 26) on
FCV outlet. Open FCV (Item 24) to 6 LPM setting.
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XII Repair Proceduresa.
b.
c. Inspect the valve stem O-ring and spring pin for wear ordamage.

Liberator

FIGURE 19: Coil and Vent Assemblies

d. Inspect the vent wrench stops on the valve body for wear ordamage.
e. Use a 3/4-in. open-end wrench to hold the outer hex flats ofthe vent valve stationary while using a 9/16-in. open-end
wrench to remove the vent extension.
f. Lightly clamp the vent valve in a vise.
g. Use a pin punch and a hammer to drive the spring pin out ofthe valve stem.
h. Use a small screwdriver to carefully pry the retainer ring off ofthe valve stem.
i. Use a dental pick or similar object to lift the O-ring off thevalve stem.
j. Replace vent valve (Item 41). Wrap the manifold vent tube 1
turn and half with Teflon Tape starting one thread back fromend. Apply a small amount of flurolubricant Krytox or Christo
lub on top of the tape and torque 2-3 turns after finger tighk. Replace shroud (see RP2)
RP17 – Warming and Breathing Coil Assembly RR(Figure 19)

NOTE: Valve must be properly aligned to allow access to handle
through hole in shroud.

WARNING: Liberator must be empty and vented before starting
procedure.

RP19 – Twist Lock QDV Lip Seal RR (Figure 20)

a. Remove shroud (See RP2).

NOTE: Lip seal may be changed on a full Liberator (Side Fill
Only).

b. Disconnect breathing coil (Item 49) by unscrewing the tube
nuts (Item 34) at the FCV (Item 24) and at the economizer(Item 35).

a. Insert lip seal tool into Liberator female QDV (Item 15). Engage
tabs on tool with slots in retaining ring (Item 87).

c. Disconnect warming coil (Item 45) by unscrewing the tube
nuts (Item 34) at the economizer (Item 35) and at the manifold.
d. Disconnect coils by snipping zip-ties (Item B) that hold themto the top of the Liberator.
e. Remove warming and breathing coil assemblies by slightly
bending them outwards and pulling them up and over the topof the Liberator.
f. To replace coil assembly, reverse above procedure.
RP18 – Vent Valve RR (Figure 19)
a. Remove shroud (See RP2).
b. Remove vent valve (Item 41) using 3/4-in open-end
wrench. Place the wrench on the valve hex flats closest to
the manifold to prevent disassembly of the valve as you
remove it.

b. Use wrench on hex end of tool. Push in on tool while turning to engage tabs on tool with slots in retaining ring (Item87). Turn tool clockwise to loosen retaining ring (Item 87).
Remove the ring.
c. Remove lip seal (Item 88) from QDV (Item 15). Jeweler’sscrewdriver may be used if necessary, but seating surfaces
must not be damaged.
d. Apply thin film of fluorolubricant to new lip seal (Item 88).
e. Place retaining ring (Item 87) and new lip seal (Item 88) on
tool.
f. Install retaining ring (Item 87) in QDV body (Item15) byturning tool counter-clockwise while pushing in on tool.
Torque retaining ring (Item 87) to 225–282 N-cm (20-25 inlbs).

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XII Repair Procedures
WARNING: Liberator must be empty and vented before starting
procedure.
a. Remove shroud (See RP2).
b. Loosen nut (Item C) by holding QDV body (Item 15) with awrench and turning nut (Item C) clockwise.

g. Inspect the poppet cartridge assembly for wear or damage.
h. To reinstall or replace the QDV (Item 11), reverse the above
procedure.
i. Apply a small amount of fluobircant Krytox or Christo Lub on
the threads of the QDV (Item 11).
j. Place pop-off sleeve over QDV.
k. Reassemble pop-off assembly to unit, ensuring spring-to-pin engagement into pop-off sleeve groove.

c. Remove QDV by pulling QDV body (Item 15) off and thenpulling the hex coupler (Item 89) and O-ring (Item 16) out of
the fill tube.

l. Replace shroud (See RP2).

NOTE: All Internal Components of the QDV Must Remain
Assembled During this Process.

RP22 – Push-on Portable Pop-Off Assembly RR (Figure 21)d. Apply thin film of fluorolubricant to O-ring (Item 16).

a. Remove shroud (See RP2).

e. Reattach QDV by matching alignment marks on valve bodyand fill tube.

b. Remove two screws (Item 37) and washers (Item 38) from
pop-off assembly (Item 27) and remove pop-off assembly.

f. Torque nut (Item C) to 60–67 N-m (45-50 ft-lbs) while holding valve body (Item 15).

c. Detach spring from bracket (Item 39) and from pop-off assembly.

g. Replace shroud (See RP2).

d. Disassemble as necessary to replace pop-off assembly parts.

FIGURE 20: Side Fill (Twist Lock) QDV Assembly

Liberator

RP20 – Twist-Lock QDV RR (Figure 20)

e. Reattach pop-off assembly to unit, being sure the pins at the bottom of the pop-off lever slide into the groove at the base of the
pop-off sleeve.
f.

Reverse the remainder of the procedure to reinstall.
FIGURE 21: Top Fill (Push-on) QDV Assembly

RP21 – Push-on QDV Assembly RR (Figure 21)
WARNING: Liberator must be empty and vented before starting
this procedure.
a. Remove shroud (See RP2).
b. Remove pop-off assembly (See RP22).
c. Remove pop-off sleeve (Item 21) from QDV (Item 11).
d. Use a 7/8-in open-end wrench to hold the body of the QDV(Item 11) stationary.
e. Use a 10-in adjustable wrench to loosen the compression nut(Item D) on the QDV (Item 11).
f. Remove the QDV (Item 11).

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XII Repair Procedures
24

RP23 – Empty Unit (Figure 22)

E

WARNING: Make sure open end of transfer line remains inside
cryogenic container. Wear insulated gloves and eye protection
when using this procedure. DO NOT reuse liquid oxygen.

DC

a. Place one end of the transfer line (Item A) into a suitablecryogenic container such as an empty, clean Liberator dewar.
Connect a male transfer line adapter (Item B) to the other endof the line.

1541

Liberator

FIGURE 22: Emptying Unit

NOTE: Female transfer line adapter should be substituted for
item B in top fill version.
b. Connect the adapter to the Liberator QDV (Item 15), keeping
the vent valve (Item 41) closed.

Bc. Liquid oxygen will be discharged from the open end of thetransfer line into the empty container. Continue process until
Liberator is empty.

Ad. If Liberator has no pressure, pressurize with the following
procedure.
1. Connect regulator (Item C) to oxygen gas source.
2. Connect pneumatic hose (Item D) to regulator andLiberator DISS Fitting (Item E).

FIGURE 23: Warming Unit

3. Adjust regulator (Item C) to supply up to 1,4 bar (20 psig).
4. Set Liberator FCV (Item 24) to 6 LPM setting.
5. Continue until Liberator is empty.

F

C

RP24 – Warm Unit (Figure 23)
a. Liberator may be allowed to sit (FCV off, vent closed) a minimum of 48 hours after emptying.
b. To warm a Liberator more quickly:

41

D

1. Connect regulator (Item C) to oxygen or nitrogen gas
source.
2. Connect pneumatic hose (Item D) to regulator (Item C) andmale pneumatic adapter (Item F).
3. Adjust regulator to 1,4 bar (20 psig). Open vent valve (Item41) to allow slow venting.
4. Allow Liberator to vent for 1-1/2 hours minimum after ventvalve (Item 41) defrosts.

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XII Repair Procedures
NOTE: Factory flow rate specifications are within the +/- 10%
tolerance required by ISO 18777 for environmental conditionsof temperature between 10oC – 32.2oC to (50oF – 90oF) andelevations up to 527 m (1730 ft).
NOTE: For flow rate test Liberator needs to be at least 1/4 to
1/2 full of properly saturated liquid oxygen.
NOTE: Be careful to allow for accuracy tolerances of flow
meter. Table 9 does not account for these tolerances.
NOTE: Flow rates will only be accurate if the reservoir is filledproperly. Reference the filling section of this manual for the correct procedure.
a. Connect FCV (Item 24) outlet to flow meter (Item G) inlet
with respiratory tubing. Make sure flow meter outlet is open
and unobstructed and flow meter (Item G) is properly
positioned.
b. Verify internal operating pressure as per RP26. Vessels
internal operating pressure should be between 19.5 psi (134kPA) and 20.5 psi (141 kPA) before beginning flow rate test.
This can be accomplished in different ways:

RP26 – Operating Pressure Test (Figure 24)
NOTE: If testing operating pressure because of improper
flow rates, test pressure immediately after flow rate test.

Liberator

RP25 – Flow Rate Test (Figure 24)

a. Connect QDV pressure test fixture (Item H). Open FCV(Item 24) to 6 LPM setting.
b. Read operating pressure on QDV pressure test fixture gauge(Item H).
c. Operating pressure must be 1,2-1,5 bar (18-22 psig) orunit fails test.
RP27 – Flow Meter Verification (Figure 24)
a. Flow meter (Item G) accuracy is best verified by acalibration laboratory. Equipment should indicate liter per
minute oxygen gas at atmospheric pressure and 21°C (70° F).
b. Flow meter (Item G) accuracy may also be tested bycomparison to one or more new, unused, calibrated flow
meters. This method will increase confidence in accuracy ofreadings, but not necessarily verify accuracy.
FIGURE 24: Flow and Pressure Tests

Option A.) If reservoirs internal operating pressure is below
19.5 psi (134 kPA) let unit sit overnight after filling, with
FCV and vent valve closed, to stabilize to normal operatingpressure. Pressure should then be verified again prior toperforming flow test.
Option B.) If reservoirs internal pressure is above 20.5 psi(141 kPA) allow unit to flow at a rate of 4 LPM for 1.5 hours
minimum prior to beginning the flow rate test.
Or
Option C.) If reservoirs internal pressure is above 20.5 psi(141 kPA) open vent valve and wait for internal pressure tostabilize at 20.5 psi (141 kPa). Ensure the QDV pressure test
fixture gauge (Item H) does not rise above 20.5 psi (141 kPa)
after FCV is closed. This will indicate the tank is ready for
beginning the flow rate test.
c. Test flow rate at each FCV (Item 24) position. Record all flow
rates.
d. Flow rates must be nominal values within tolerances listed inTable 9 or unit fails flow rate test.

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XII Repair Procedures
TABLE 9: Flow Test Acceptable Ranges

Liberator

FIGURE 25: Economizer Regulator

FIGURE 26: Economizer Test Setup

NOTE: SLPM is corrected to normal temperature and pressure(70˚F & 14.7 psig or 21˚C and 1.01 Bar). The above acceptableflow rates are intended for field testing only of flow control
valves to account for variation in elevation and temperature.
This table reflects tolerance requirements of ISO 10524. This
does not affect CAIRE's factory compliance with the +/-10%
tolerance requirement of ISO 18777.

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XII Repair Procedures
RP28 – Economizer Regulator RR (Figure 25)
WARNING: Liberator must be empty and vented before starting
this procedure.
a. Remove shroud (See RP2).

WARNING: Liberator must be empty and vented before
starting this procedure.
NOTE: Special care should be taken in aligning the FCV inorder to ensure that it lines up properly with the shroud.
a. Remove shroud (See RP2).

b. Loosen the three compression fitting nuts (Item 34) at theeconomizer regulator (Item 35). Move coils (on the sides)and economizer tube (Item D) away from the economizer
regulator (Item 35).

b. Loosen compression fitting nut (Item 34) at connection ofbreathing coil (Item 49) and FCV assembly. Disconnect FCV
assembly (Item 24) from coil.

c. Follow RP29 to ensure proper settings on the replacement
regulator.

c. Remove the FCV knob (Item 1) by grasping firmly and pulling upwards.

d. Reverse remainder of procedure to install new properly adjusted regulator.

d. Unscrew the two screws (Item 4) holding the lock plate (Item3) and decal (Item 2) to the FCV (Item 24) and remove lockplate and decal.

RP29 – Economizer Regulator TestWARNING: Liberator must be empty and vented before starting
this procedure.

Liberator

RP30 – Flow Control Valve RR (Figure 27)

e. Replace the FCV (Item 24), by reversing the above procedure.

FIGURE 27: Flow Control Valvea. Follow steps a and b of RP28 to remove economizer regulator.
b. Connect the oxygen pressure source to the inlet of the economizer regulator (Item 35) as shown in Figure 25. The inlet isthe side attached to the economizer tube (Item D, Figure 25).
c. Open the pressure source valve. Adjust the pressure source regulator to 1,6 bar (23 psig). The economizer regulator should
be set to open at 1,45 bar (21 psig) and close at 1,31 bar (19psig).
d. Slowly open valve (Item B) just enough to allow some gas toescape.
e. Pressure gauge (Item A) will indicate the setting of theeconomizer regulator.
f. Reverse steps a and b of RP28 to reinstall regulator.
Note: If the economizer is suspected to be malfunctioning, pleasecontact Technical Service.
WARNING: Liberator must be empty and vented before starting
this procedure.
RP31 – Dewar RR
a. Remove shroud (See RP2).
b. Remove manifold assembly and coils (See RP9).
c. Remove condensate bottle, drain tube and bracket (see RP3).
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XII Repair Procedures
d. Remove dewar cap from the new dewar and place the cap on old
dewar.

1. Weigh the empty reservoir and record the weight (kg/lb)

e. Clean/dry both the probe and dewar following procedure in
section VIII.

2. Fill the unit with properly saturated liquid oxygen (Per
Filling Procedure in Operation section of manual)f. Connect the manifold assembly with coils to the new dewar;
be sure to follow the manifold assembly replacement procedure (See RP9). Do not replace shroud.

3. Weigh the full reservoir and record the weight (kg/lb)

g. Replace condensate bottle, bracket and drain tube.
h. Scribe part number and serial number on new dewar handle.
Make part number and serial number on old dewar illegible.
i. Calibrate meter by following RP7.

RP32 – Normal Evaporation Rate Testa. Fill the unit with at least 9 to 11 kgs (20 to 25 lbs) of properly
saturated liquid oxygen.
b. Allow unit to sit undisturbed for a minimum of 12 hours with
the FCV in Off position and the vent closed.
NOTE: Scale must be accurate to ± 0.02 kg (0.05 lbs).
c. Weigh unit. Record weight and time.
d. Allow unit to sit undisturbed for a minimum of 24 hours.
e. Weigh unit. Record weight and time.
f. Calculate liquid loss rate (NER) using the following formula:
Weight lost (kg or lbs)
NER = —————————— x 24 hours/day
Elapsed time in hrs.
Example0.63 kg
NER = ————— x 24 hours/day
25.5 hrs.
NER = 0,59 kg/day
g. If NER is more than 0,9 kg/day (2 lbs/day) for a Liberator,
the dealer may want to send the unit to CAIRE, Inc. for reevacuation. If NER is more than 2,3 kg/day (5 lbs/day) the
dealer should remove the unit from service and have the unit
re-vacuumed.

Liberator

RP33 – Determining Liquid and Gaseous Oxygen Capacity

4. Subtract the empty reservoir weight (STEP 1) from thefull reservoir weight (STEP 3) to determine the weight ofliquid oxygen that is inside of the reservoir
5. Take the weight of liquid oxygen (calculated in STEP 4)
and divide it by the LOX density to calculate the liters ofliquid oxygen in the reservoir
NOTE: The density of liquid oxygen will vary based on operation and saturation pressures. The densities provided in thespecifications section of this manual, which are to be used in
the above calculation, are representative of optimum operation and saturation pressures. Due to rounding and conversion accuracy, a range of 0.10 L is acceptable in calculation.
NOTE: If proper filling procedures (primarily source pressure)are not followed per the filling procedure in operation section of this manual, reservoir will not be at nominal pressure
immediately following the fill process. In addition, if PRV, SRV
and/or Economizer are not performing within ranges specified in the Specifications section of this manual, the reservoir
will not be at nominal pressure immediately following the fillprocess. If either or both of these conditions occur, calculations using the nominal densities listed in the Specifications
section of this manual, will not be accurate.
Example: Calculation of Liquid Oxygen in a full Liberator 45
reservoir
1. Empty weight of LIB 45 Reservoir: 24,95 kg (55.00 lbs)
2. Filled unit with properly saturated liquid oxygen
3. Full weight of LIB 45 Reservoir: 74.99 kg (165.32 lbs)
4. 74.99 kg (165.32 lbs) – 24,95 kg (55.00 lbs) = 50,04 kg(110.3 lbs)
5A. 55.04 kg/1.095 kg/L = 45.7 Liquid Liters of Oxygen
5B. 110.3 lbs/2.413 lbs/L= 45.7 Liquid Liters of Oxygen

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XIII Service Tools/Equipment/Supplies
1. Hex Wrenches (various sizes)

Cleaner
1. Simple Green available at www.simplegreen.com

2. Flat Blade Screwdriver
3. 5/16” Nut Driver
4. Open End Wrenches (1/2” to 1-1/8”)

Tools and Accessories available from Caire
Part No
Description

5. Side Cutters10679862

Female Top Fill Pneumatic Test Adapter

10678157

Female Top Fill Transfer Line Adapter

CA200071

240 AC Fluorolubricant

6. Pliers
7. Torque Driver/Wrenches:
12-17 N-cm (10-15 in-lbs)
23-29 N-cm (20-25 in-lbs)
69-92 N-cm (60-80 in-lbs)
104-115 N-cm (90-100 in-lbs)
6.2-6.9 N-m (45-50 ft-lbs)
8. Jeweler’s Screwdriver
Required Fixtures/Equipment
1. Capacitance Meter
2. Soldering Iron

Leak Detection Fluid (gallon)
B-775311-00 Erie “Liter Meter”
Erie "Liter Meter" 6-15lpm
10995620
97212021

Male Side Fill Pneumatic Test Adapter

97212023

Male Side Fill Transfer Line Adapter w/Filter

15075347

Transfer Line Adapter Cover

97217007Pressure Gauge Adapter

CA400004

Replacement Filter/Male Transfer Line Adapter

97202005

Vent Valve Wrench

4. Pressure Gauge

B-775182-00 Vent Valve Wrench
Capacitance Meter
97403015

5. Pressure Gauge Adapter

3910486

Dewar Cap

6. Flowmeter

97403577

0-4.1 bar (0-60 psig) Pressure Gauge Transfer Line

7. 02 Gas Source (High Pressure bottle)

97404564

Swivel Connector

8. 02 Liquid Source

97405279

Pneumatic Hose with DISS Fittings Liquid

9713119

Oxygen Transfer Line – 1.8 m (6 ft)

97405590

Lip Seal Service Tool

CA406310

TEFLON Tape
10.3 bar (150 psi) Relief Valve Only

97406555

Super Flex Liquid Oxygen Transfer Line – 6’

13350704

Service Manual

13329091

G4 Capacitance Meter Adaptor Kit

20802161

QDV Hex Plug w/o O-Ring Top fill plug

10566446

Cap Brass 15/16” Hex Side fill Plug

CA404828

Hex Coupler O-Ring for Side fill plug

3. Oxygen Regulator

9. N2 Gas or Clean, Dry Compressed Air Source
10. Tubing (02 compatible)
11. Lip Seal Service Tool
12. Male Pneumatic Test Adapter
13. LO2 Transfer Line
14. Transfer Line Adapter with Filter
15. Dewar Cap
16. Vent Valve Wrench
17. Scale 0-70 kg (0-150 lbs), 0.02 kg (0.05 lb) increments
Required Supplies

Liberator

Required Tools

1. Stay-Clean Flux
2. Cotton Swabs
3. Lead-free Solder
4. Distilled Water
5. Household Glass Cleaner
6. Lint-Free Cloth
7. PTFE Tape
8. Fluorolubricant
9. Leak Detection Fluid
Liberator Technical Service Manual • PN 13350704 Rev M

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XIV Parts Price List
Liberator

Contact Customer Service or visit www.caireinc.com to
obtain your parts list.

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XV Ordering Information
Liberator

Ordering Information
The following steps should be used when ordering a new Liberator
or replacement parts for an existing unit:
1. Compile a list of all equipment and replacement parts to beordered.
NOTE: Use the following numbers to order a complete unit.
Model(0–15 LPM)

Side Fill

Top Fill

Dual Fill

L20

13256435

13256654

13256195

L3013258449

13258641

13256929

L3713259695

13259919

13259599

L4513262085

13262253

13261699

L60

13263782

13263811

13263758

2. Fill out a purchase order containing the following information:a. Purchase order number.
b. Name and address of billing location.
c. Name and address of shipping location.
d. Quantity, part number, description, and unit costfor each item ordered.
3. Contact your local CAIRE office to begin processing of yourorder. CAIRE office details can be located on our website atwww.caireinc.com and navigating to the Corporate tab, andlocations or https://www.caireinc.com/caire-inc-corporate-landing-page/locations/ Here you will find the local officeaddress, email address and phone number.

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XVI Return Policy
Liberator

When a Liberator is received, it should be inspected immediately,as outlined in Section VII, Unpacking and Setup Instructions.
If a problem with the unit should be encountered, reference
should be made to the Troubleshooting Chart in Section X, page
20-23. If these procedures do not provide a solution for the problem, the following steps should be taken:
1. Call CAIRE Inc. Customer Service. State the problem withthe unit. If it is determined that the problem cannot be
solved by the distributor, a Return Material Authorization(RMA) number will be assigned to the unit or part(s). If a
Purchase Order Number is to be referenced, please give thisnumber to the Customer Service Representative at that time.
2. Carefully package the parts, or repack the unit in its original
shipping container, precisely as shipped.
3. Write the Return Authorization Number on the top of theshipping container.
4. Return the unit or parts by professional carrier to theaddress provided by CAIRE Customer Service.

All equipment returned to CAIRE Inc. must be shipped“prepaid”.
When the defective item(s) is received at CAIRE Inc., it will beserviced and returned to the distributor as soon as possible. A
copy of the “Repair Cost Sheet” will be enclosed giving a detailed
listing of any maintenance performed.

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www.caireinc.com

CAIRE and CAIRE Inc. are registered trademarks of CAIRE Inc. Please visit our website
below for a full listing of trademarks. Trademarks: www.caireinc.com/corporate/
trademarks/
Copyright © CAIRE, Inc. 2024. CAIRE Inc. reserves the right to discontinue its products,
or change the prices, materials, equipment, quality, descriptions, specifications and/or
processes to its products at any time without prior notice and with no further obligationor consequence. All rights not expressly stated herein are reserved by us, as applicable.

11 June 2024 - Liberator Technical Service Manual • PN 13350704 Rev M