Panasonic OCU-CR400VF8 Operating instructions

ENGLISH
Outdoor Type Refrigeration Unit
(Non-fluorocarbon Refrigeration Unit with CO2Refrigerant)
Operating Instructions and Installation Instructions
Panasonic Corporation
1006 Kadoma, Kadoma City, Osaka, Japan
CONTENTS
Cautions for Safety.......................................................2-8
Name of Each Part .......................................................... 9
Scope of Application, Specifications.........................10-11
For Effectively Using the Refrigeration Unit.............. 12-13
Selection of Installation Location..............................13-14
Carry-in/Installation....................................................14-15
Installation Example ......................................................16
Refrigerant Piping Work ...........................................17-18
Piping Example..............................................................19
Refrigerant Circuit Diagram........................................... 20
Refrigerant Charging................................................21-22
Cautions for Electrical Wiring Work............................... 23
Electrical Wiring Work ..............................................24-25
Electrical Circuit Diagram .........................................26-27
What Needs to be Checked before Operation............... 28
Setting and Indication............................................... 29-33
Control Functions .....................................................34-36
Adjustment during Operation....................................36-37
About Alarms ............................................................38-40
Maintenance and Inspection.......................................... 41
Actions at the time of Failure .................................... 42-43
Failure Diagnosis......................................................44-50
Makings for Directive 2014/68/EU (PED) ...................... 51
Model No. OCU-CR400VF8 /OCU-CR400VF8SL
Thank you very much for purchasing Panasonic products this time.
Please read this instruction booklet and correctly comply with the explanations.
In particular, please read "Cautions for Safety" (Pages EN2 to EN8) for ensuring safe
operations.
Please retain this instruction booklet in a safe place.
Caution labels are attached to the product.
This illustration represents OCU-CR400VF8 •The English text is the original instructions.
Other languages are translation of the original
instructions.
NOTICE

For the purpose of avoiding harm to people and damage to properties, items to be complied with are explained here.
■Explanations are classified by degree of harm or damage caused by incorrect use.
WARNING Indicates possibility of death or serious injury.
CAUTION Indicates possibility of minor injury or damage to properties.
■Items to be observed are explained by the following pictograms.
Indicates what you should not do.
Indicates what you must do.
WARNING
Installation Work
Installation to be made by manufacturer’s
service personnel or similarly skilled person.
Incorrect installation work may
lead to malfunction such as
abnormal vibration,
and generates
refrigerant gas leak, electrical
shock, or fire.
Do not use other than the designated
refrigerant (for charging, adding or
recharging)
Non-designated refrigerant may
cause equipment failure or burst,
or injury.
Appliances employing R744 refrigeration
system.
System contains refrigerant under
high pressure. Do not tamper with
the system. It must be serviced by
qualified persons only.
Securely complete refrigerant piping before
carrying out airtight testing.
Refrigerant gas leak may cause
suffocation.
Cautions for Safety (Be sure to comply with the following)
EN - 2

ENGLISH
Installation Work
Installation should be made securely on a
place that can fully support the mass of the
refrigeration unit.
Insufficient foundation may
cause
falling or dropping, and lead
to refrigerant gas leak, injury,
electrical shock, or fire,
●Refrigeration unit should be
secured on a concrete base
with a mass approximately
3 times that of the unit and
fastened with anchor bolts.
Perform airtight test before charging
refrigerant.
Refrigerant gas leak may cause
insufficient oxygen and lead to a
death accident.
●Carry out airtight test and
confirm no leak of refrigerant.
Install the safety cover.
Touching the refrigeration unit
by hand of the people other than
the designated operators may
cause injury.
●Install a safety cover or
protective fence.
Piping, equipment components and tools
should be exclusively for R744 (CO2
refrigerant).
Use of components for HFC
refrigerant may cause serious
accidents such as equipment
failure and rupture of the
refrigerant cycle.
Electrical Work
Always use a dedicated circuit and install a
ground fault protector.
Incorrect electrical work may
lead to current leak and fire or
electrical shock.
●Wiring work should conform to
the installation instructions.
Grounding Work
Lack of grounding work may
lead to electrical shock caused
by current leak.
●Securely carry out grounding
work by qualified technicians.
Electrical wiring should use the specified
cable and to be properly secured.
When the specified cable is
not used, or connection or
securing is incomplete, electrical
resistance becomes larger and
may cause abnormal heating or
fire.
●Use the specified cable and
properly secure it on an
appropriate location.
Securely place the cover on the electrical
box and enclosure panel.
Incomplete attachment may
lead to penetration of water and
living creatures, thereby causing
current leak and fire/electrical
shock.
●Confirm that covers are
securely installed.
EN - 3
Cautions for Safety (Be sure to comply with the following)

Cautions for Safety (Be sure to comply with the following)
Cautions for Use
Do not change the set values of the safety
device.
Using the refrigeration unit with
changed values may cause
failure of the safety stop function
and lead to a burst or fire.
●Do not change the set values
of the safety device. If they
are changed unintentionally,
shut off the power switch and
ground fault protector and
consult with the distributor.
Do not insert a finger, stick or foreign
object into the ventilation opening and fan
guard of the enclosure panel.
Such object may hit the fast
rotating fan and result in injury.
When water or other material gets into the
electrical box, turn off the power switch
and shut off the ground fault protector.
Continued use may cause
short-circuit, leading to fire or
electrical shock.
●Do not splash water on
electrical components or wash
them with water.
When the ground fault protector activates,
report to the specialty company.
Forced recovery of power may
cause current leak, leading to
fire or electrical shock.
For the purpose of controlling
concentration of refrigerant gas, install a
leak detector and mechanical ventilation
equipment in the refrigerant-handling
facility (inside the room).
Refrigerant gas leak may cause
suffocation.
Restriction on use of equipment
The appliance is not to be used
by persons (including children)
with reduced physical, sensory
or mental capabilities, or lack
of experience and knowledge,
unless they have been given
supervision or instruction.
Consideration for children
Children shall not play with the
appliance.
«In the European Market»
Children should be supervised
to ensure that they do not play
with the appliance.
«In the Australian and New
Zealand market»
Restriction on use of equipment
This appliance can be used by
children aged from 8 years and
above and persons with reduced
physical, sensory or mental
capabilities or lack of experience
and knowledge if they have
been given supervision or
instruction concerning use of
the appliance in a safe way
and understand the hazards
involved.
«In the European Market»
Cleaning and maintenance by trained person.
Cleaning and user maintenance
shall not be made by children
without supervision.
«In the European Market»
EN - 4

ENGLISH
Cautions for Use
Restriction on use of equipment
This appliance is not intended for use by persons (including children) with
reduced physical, sensory or mental capabilities, or lack of experience and
knowledge, unless they have been given supervision or instruction concerning
use of the appliance by a person responsible for their safety.
«In the Australian and New Zealand market»
Repairs
Disassembly or repairs should be
performed by a specialty operator.
Incorrect disassembly or repair
may lead to abnormal operation
and causes injury, fire or
electrical shock.
●Request a specialty operator
to perform disassembly or
repair work.
Do not absolutely perform
modification.
When abnormal operation was detected,
or before starting disassembly or repair,
turn off the power switch and shut off the
ground fault protector.
Continued operation with
abnormal condition, or
disassembly/repair without
shutting off the power would
lead to current leak or short-
circuit and may cause fire or
electrical shock.
Specified components must be used for
repair.
Use of non-specified
components may cause failure
of the safety stop function and
lead to burst or fire.
●Consult with the distributor.
Stop the compressor before disconnecting
the refrigerant piping.
Disconnecting the piping while
the compressor is in operation
would cause abnormally high
pressure with air intake, and
may lead to a burst or injury.
Replacing the power cord.
If the supply cord is damaged,
it must be replaced by
manufacturer, its service agent
or similarly qualified persons in
order to avoid ahazard.
Contact technician.
If any leak of refrigerant is
detected, contact the authorized,
licensed and qualified technician
to repair the system.
Moving or Change of Installation Location
Request a certified installer for moving or
changing the location.
Incorrect installation or moving
work may lead to malfunction
such as abnormal vibration, and
generates refrigerant gas leak,
electrical shock, or fire.
EN - 5
Cautions for Safety (Be sure to comply with the following)

CAUTION
Installation Work
Do not install in a
place with possible leak of
flammable gas.
Leaked flammable gas around
the
refrigeration unit may catch fire
from a spark of a switch and lead
to fire.
Produce a refrigeration cycle within the
limits of an operation standard (Scope of
Application).
Non-standard refrigeration cycle
may generate abnormal high
pressure and abnormal heat
generation, thereby causing
burst,
smoke generation, fire and
current
leak.
Apply a drain work according to the need.
Without consideration of drain
water processing, moisture from
rainwater and defrosted water
generates mold and moss, and
may cause slipping on the floor.
Apply heat insulation on the suction
line and
liquid line.
Lack of heat insulation generates
water from condensation and
mold
and moss, thus causing slipping
on the floor.
Install in a place without air stagnation.
Leak of refrigerant gas may
cause
insufficient oxygen and harm
human health.
●Install in a place with good
ventilation.
Request a specialty operator for moving the
refrigeration unit.
Incorrect moving may cause
falling
or dropping of the refrigeration
unit, and cause injury.
●Refrigeration unit is a heavy
item. Always consult with a
specialty operator.
Electrical Work
Always install a ground fault protector with
the specified capacity.
Incorrect capacity does not
operate safety stop function
and may lead to fire or electrical
shock.
Ground fault protector needs
to follow IEC60364-4-44
443,overvoltage category III.
(Impulse withstand voltage value
4kV.)
Do not include electrical wiring in the heat
insulation material.
Condensation of piping may
cause current leak and fire
caused by overheating.
EN - 6
Cautions for Safety (Be sure to comply with the following)

ENGLISH
This product is intended for professional
use.
Permission from the power
supplier is required when you
connect this unit to a 16A
distribution network.
Cautions for Use
When the refrigerant bursts out, shut off
the
power and fully close the service valve.
Blowout of refrigerant from the
refrigeration cycle by opening
the service port would cause
insufficient oxygen and harm
human health.
Do not use flammable spray near the
refrigeration unit. Do not place flammable
materials nearby.
Flammable material may catch
fire from switch spark.
Do not touch electrical components by a
wet hand.
Switching operation by a wet
hand may cause electrical shock
and injury.
Before any inspection service, turn off the
power switch and shut down the ground
fault protector.
Inspection work with power
on may lead to electrical
shock, interference with the
moving mechanism, and heat
generation, thereby leading to
injury and skin burn.
Periodically check operation of the ground
fault protector.
Failed interrupter does not
operate safety stop function
and may lead to fire or electrical
shock.
Do not touch the fin of the gas cooler.
Touching the fin and sliding
along the fin may cause skin cut
by the fin edge.
Do not ride on the refrigeration unit.
Riding on the refrigeration unit
or placing an article on it may
lead to falling or dropping by
vibration and cause injury.
Emergency (Leakage, Fire or Explosion).
Do not attempt to operate
or repair the unit during
emergencies if it is not safe to
do so.
Periodically check the installed base.
Damaged base after a long-time
use may cause the refrigeration
unit to fall or drop and lead to
injury.
EN - 7
Cautions for Safety (Be sure to comply with the following)

Disposal
Request a specialty operator for disposing
the refrigeration unit.
The refrigeration system is under
high pressure. Disposal with
the refrigerant and oil inside the
refrigeration unit may cause fire
or explosion.
Before disposal
The refrigeration system is
under high pressure. Do not
tamper with it. Contact qualified
service personal before
disposal.
Disposal of Old Equipment
Only for European Union and countries with recycling systems
This symbol on the products, packaging, and/or accompanying documents
means that used electrical and electronic products must not be mixed with
general household waste.
For proper treatment, recovery and recycling of old products, please take them
to applicable collection points in accordance with your national legislation.
By disposing of them correctly, you will help to save valuable resources and
prevent any potential negative effects on human health and the environment.
For more information about collection and recycling, please contact your local
authority.
Penalties may be applicable for incorrect disposal of this waste, in accordance
with national legislation.
EN - 8
Cautions for Safety (Be sure to comply with the following)

ENGLISH
Name of Each Part
Electrical box internal layout
Accessories
Name Model No. Applicable refrigeration unit Remarks
Suction filter S-008T
OCU-CR400VF8
OCU-CR400VF8SL
Prevention of dust penetration
Filter Dryer D-152T
(Type: CO-082-S)
φ6.35
(Outer diameter welding)
Service piping SPK-TU125 Option
Note: Service piping are not included the unit.
The filter dryer and suction filter (shipped with each refrigeration unit) are standard components. When
replacing the filter dryer and suction filter, use the same ones shown above as the Accessories.
EN - 9
Liquid tube electromagnetic valve terminal base
External alarm terminal base
Communication terminal base
Power source
terminal base
Showcase operation
terminal base
Reactor
Control terminal base
Left side of refrigeration unit Left side of refrigeration unit
without MTG for CRD2-EN PCB
CR2-EN PCB CR2-EN PCB
CRD2-EN PCB
INV4-H-EN PCB
INV4-MF-EN PCB

EN -10
Scope of Application,Specifications
This refrigeration unit operates with a rotary compressor.
Use the refrigeration unit within the range shown below.
Item Standard Value Remarks
Refrigerant R744 The charge supply amount shall be
adequate
Evaporating temperature -20 °C to -5 °C Temperature conversion of inlet
pressure
Suction pressure 1.87MPa to 2.95MPa Unit inlet pressure
Compressor rotational speed 40 s-1 to 80 s-1 *(RPS)
Suction gas temperature 18 °C or below Unit inlet (suction gas) pipe
temperature
Superheat at suction 10 K or above Difference between evaporating temperature
and compressor inlet temperature
Discharge pressure 9.1MPa or below
(except transient)
Compressor outlet pressure
Discharge gas temperature 115 °C or below Compressor outlet temperature
Oil temperature 100 °C or below
(Ambient temperature +10 K or above)
Ambient temperature -15 °C to +43 °C Gas cooler intake air temperature
Power source 50 Hz 380 V / 400 V / 415 V 3N ~Within ±10 % of Rate Voltage
Installation inclination angle 1° or below
ON/OFF cycle period 10 minutes or longer
for ON/OFF cycle
Oil return shall be ensured
Installation Outdoor The foundation shall be rigid enough
Climatic class 0/1/2/3/4/6/8 Please see below “CLIMATIC CLASS”
Net Weight 136 kg
* Operation may not be possible depending on the installed condition.
CLIMATIC CLASS
Test room
climate class
Dry bulb temperature
°C
Relative humidity
%
Dew point
°C
Water vapour mass
in
dry air
g/kg
020 50 9.3 7.3
116 80 12.6 9.1
222 65 15.2 10.8
325 60 16.7 12.0
430 55 20.0 14.8
627 70 21.1 15.8
823.9 55 14.3 10.2
Excerpt from: EN ISO 23953
Countermeasures in a cold weather operation
In order to prevent excessive reduction of high pressure in a cold weather location, surrounding around the
refrigeration unit should be made.

ENGLISH
Scope of Application,Specifications
EN -11
Rated Specifications
Item Rating Unit
Power source 50 Hz 380 V / 400 V / 415 V 3N ~ V
Power input 4.00/4.00/4.00 kW
Current 6.48/6.14/5.93 A
Conditions
1. Evaporating temperature: -10 °C
2. Ambient temperature: 32 °C
3. Compressor rotational speed : 80 s-1
4. Suction superheat : 10K
Performances (380 V / 400 V / 415 V)
Evaporating
temperature t -10 °C °C
Annual electricity
consumption Q16337 kWh/a
Seasonal energy
performance ratio SEPR 2.68-
Compressor rotational speed : 80 s-1, Suction superheat : 10K
Sound pressure level
The A-weighted sound pressure level does not exceed 70 dB(A).
(at a distance of 1 m from surface of product)
CO2 Refrigerant Grade
Charge CO2 refrigerant (R744) that is compatible with following specifications.
Item Specifications
Purity > 99.9 %(volume)
Moisture < 0.005 %(volume)
Total sulfur < 0.03 ppm (weight)
Inert gas (H2, N2, O2,Ar) < 0.01 %(volume)
Ambient
temperature Item Symbol Evaporating
temperature Unit
T -10 °C
32 °C
Cooling capacity PA7.120/7.120/7.120 kW
Power input DA3.950/3.950/3.950 kW
COP COPA1.80/1.80/1.80 -
25 °C
Cooling capacity PB7.320/7.320/7.320 kW
Power input DB3.500/3.500/3.500 kW
COP COPB2.09/2.09/2.09 -
15 °C
Cooling capacity PC7.480/7.480/7.480 kW
Power input DC2.870/2.870/2.870 kW
COP COPC2.61/2.61/2.61 -
5 °C
Cooling capacity PD7.610/7.610/7.610 kW
Power input DD2.420/2.420/2.420 kW
COP COPD3.14/3.14/3.14 -
43 °C
Cooling capacity P35.550/5.550/5.550 kW
Power input D34.730/4.730/4.730 kW
COP COP31.17/1.17/1.17 -

EN -12
For Effectively Using the Refrigeration Unit
Cautions for Installation Work
This refrigeration unit has been designed exclusively for R744 (CO2refrigerant).
Refrigeration oil and each component including the compressor have been exclusively designed for the refrigeration
unit.
Please use sufficient caution for maintaining the reliability of the product.
(1) Since CO2 refrigerant becomes high pressure during the operation, use the piping material and other
components particularly designed for CO2 refrigerant with sufficient strength.
(2) As the refrigeration oil absorbs moisture, opening time should be as short as possible. Connection of the
piping to the refrigeration unit should be made at the last stage of piping installation work. Avoid outdoor
work on a rainy day.
(3) For piping work, use “phosphorous-deoxidized copper pipe” of refrigeration grade, clean, dehydrated and
“phosphor-copper brazing solder”.
If “silver brazing solder” is to be used, do not use any flux containing chlorine. During pipe brazing it is a must to
use nitrogen over pressure.
(4) Do not use pipe joints made for HFC refrigerant, because they do not have the required strength. In addition,
absolutely do not use flared joints.
(5) For the purpose of protecting the refrigeration unit and refrigeration cycle, be sure to install the included filter dryer
at the liquid line of the refrigeration unit.
(6) Gas leak detector used for airtight test should be foaming liquid or soap water. Do not use kitchen detergent.
Kitchen detergent may corrode metals.
For Economically Using the Refrigeration Unit
For the purpose of using the refrigeration unit economically, consider the followings.
Cooling capacity largely varies by the method of use.
When evaporating temperature falls by 1K, cooling capacity decreases by 3 to 4%, and increase of discharge pressure
decreases cooling capacity and increases power consumption.
In order to fully extract the unit performance, compressor suction pressure should be increased as high as possible,
and discharge pressure should be made as low as possible.For this reason, caution should be used in the following
points.
(1) Make the piping resistance as small as possible.
Ref: Capacity change rate per 1 °C pressure loss of suction line
Evaporating temperature Capacity change rate per 1 °C
-20 °C to -5 °C 3 % to 4 %
(2) Select an evaporator of sufficient capacity for raising evaporating temperature as high as possible.
(3) Do not block the cold air outlet in a refrigerator or showcase with food items.
(4) Operate door opening of a refrigerator as quickly as possible. (To avoid leak of cold air, reduce the time of door
opening)
(5) The gas cooler should be cleaned periodically to avoid clogging.

ENGLISH
Caution for an Inverter-based Refrigeration Unit
(1) Even after turning the power OFF, voltage still remains in the charged part. Until the LED (red) of the INV4-H-
EN PCB turns off (until the capacitor discharges the potential), approximately 5 minutes are required. Do not
touch the charged part.
(2) Phase-advancing capacitor is prohibited
Do not attach a phase-advancing capacitor to an inverter compressor. It may cause inverter failure or capacitor
breakage.
(3) Inverter noise prevention
Take as much distance as possible from the wiring of a radio receiver or wired broadcasting.
Inverter noise may cause undesired noise sound.
(4) The two-stage compression mechanism prevents temperature rise of the second stage discharge gas of the
compressor.
During the operation with a small quantity of refrigerant in the refrigeration circuit, a protection device (the CR2-
EN PCB) makes the compressor to stop. Avoid refrigerant shortage operation.
(5) Rotary compressor consists of high precision components. Use caution during piping work to avoid contamination
of dust, metal powder, or oxide scale, etc.
Initial Oil Quantity
EN -13
Model No. Compressor Oil separator
OCU-CR400VF8(SL)600mL 550mL
Oil type PZ-68S
When adding or changing oil, be sure to use our specified oil.
General Cautions
Each unit of the equipment should be placed by selecting the most convenient location such as easy to install,
operate or maintain.
(1) Each unit should be placed to make the piping and wiring length as short as possible and easy to install.
(2) Controller should be located within the reach of the user’s hand for convenient daily operations (RUN, STOP,
reset warning, etc.). Do not locate the controller in a place easily accessed by the people other than the user.
(3) Install the refrigeration unit at a location easy to be serviced for daily maintenance and inspection.
Daily maintenance and inspection involves checking the operation pressure, compressor operation condition for
abnormal sound or vibration.
For Effectively Using the Refrigeration Unit
Selection of Installation Location
Caution

EN -14
Selection of Installation Location
Location not disturbing neighbors
Avoid air-blow from the gas cooler to the neighbor’s window or noise to disturb other people.
Location with a sturdy and level surface
Install the refrigeration unit on a firm foundation to avoid an increase of noise and vibration. Particularly at the
boundary from the neighbor’s lot, comply with the regional laws and regulations.
Location away from a heat source
Installation should not be affected by reflection from the floor.
Location with good ventilation
To ensure good ventilation, installed location should ensure the intake air by the gas cooler is 43 °C or below with
good airflow.
Location not affected by a wet floor
The refrigeration unit is often affected by rainwater and drain water from defrosting. Apply drain water work as required.
Location not affected by snow accumulation
In a cold weather location, a roof should be furnished to avoid snow accumulation and frosting or freezing.
Direction for avoiding strong wind
Install the refrigeration unit with its blow-out side facing perpendicular to the wind direction.
Carry-in Operation
(1) Carry the refrigeration unit gently by keeping the vertical position as much as possible.
(2) Absolutely avoid a lay-down position of the refrigeration unit.
(3) When conveying the refrigeration unit with a forklift, maintain the unit vertically by using the square holes at the
corners of the unit base.
Hang Operation
When hanging the refrigeration unit, use caution for the following points.
When hanging the refrigeration unit, follow the “Precautions for Hanging the Product” attached to the refrigeration unit.
When hanging and conveying the refrigeration unit, keep it level without causing any impacts.
Hang rope, etc. must be strong enough to withstand the weight of the refrigeration unit.
Carry-in/Installation

ENGLISH
Carry-in/Installation
Foundation/Platform Work
●As a reference, the foundation should be made from concrete having a mass about 3 times that of the
refrigeration unit. (Absorbing vibration by mass)
●Vibration should be reduced by aplatform or anti-vibration pad for avoiding transmission of vibration to the floor and wall.
●To avoid falling, secure the refrigeration unit by using anchor bolts. (Use all securing positions)
●The refrigeration unit must be installed with an inclination angle 1°or below.
●The refrigeration unit must be installed below the altitude of 2,000 m.
If a foundation meeting the requirement above cannot be secured, be sure to check that no abnormal vibration is
generated by resonation of the refrigeration unit and piping system.
(1) Basic foundation work when the pipe is extended horizontally.
On a concrete foundation 150 mm or higher from the floor surface, place anti-vibration pads (Approx. 8 to 15 mm
thick) and secure the unit on the entire unit base with anchor bolts.
(2) Basic foundation work when the pipe is extended downward.
Form an elevated foundation with vertical columns.
Place an anti-vibration pad (thickness of 8 to 15 mm) on the entire surface of the foundation and secure it with
anchor bolts.
(3) Anchor bolts
Use M8 size anchor bolts and buried at least 100 mm on the concrete foundation.
Fix the unit with double nutsand plain washers(28 mm O.D. minimum).
External Dimensions
Optional Accessories
The following service piping (optional) is required for the installation and
service work of the refrigeration unit.
Service piping for Evacuation, Airtight test, and Refrigerantcharging
(Model No. SPK-TU125)
(Units: mm)
EN -15

Installation Example
EN -16

ENGLISH
Refrigerant Piping Work
EN -17
Design and installation of the refrigerant piping work largely affect the performance of the refrigeration unit as well
as the product life and problem occurrence.
Installation work should comply with the following items. Installation of all equipment have to be in accordance to
Pressure directive 2014/68/EU and European norm EN 378 «In the European Market».
Or, Australian norm AS/NZS 5149 «In the Australian and New Zealand market».
Selection of Refrigerant Piping Size
The connection piping size for refrigeration unit is, in principle, as shown below, but each should be determined by
calculating pressure loss of the piping and refrigerant flow speed and making sure no problem occurs in the cooling
capacity and oil return.
As refrigeration unit using CO2 refrigerant incurs pressure higher than when using HFC refrigerant, it is necessary to
choose adequate materials.
Model No. Suction line (Unit inlet) Liquid line (Unit outlet)
OCU-CR400VF8(SL) Ø12.7 mm, 1/2” Ø9.52 mm, 3/8”
Note: Welding is outer diameter welding.
●Piping material should be seamless phosphorous-deoxidized copper pipes (refrigeration grade), K65.
●When cutting pipe, use a pipe cutter and always remove burrs.
●When bending pipe, secure a bending radius 4 times or greater of the outer diameter. During bending, pay attention
to distortion and scars.
●When the connection length of the suction line is 15 m or shorter, increase piping size by 1 rank for improving
startability of the refrigeration unit. To secure starting performance.
(Piping size of the suction line: Ø 12.7 mm → Ø 15.88 mm)
Use sufficient caution for handling piping by sealing the pipe end with tape or any other cover for
avoiding entry of contaminants and moisture into the pipe.
Caution
Installation Example

Refrigerant Piping Work
Cautions for Heat Insulation Work
●Apply heat insulation on the suction line and liquid line for avoiding thermal effect from outside.
●Do not wrap together the suction line and liquid line with heat insulation material.
(Refer to the right illustration)
●Apply heat insulation only after executing airtight and pressure test.
Prevent contamination of foreign objects such as dust, metal powder, oxide scale,
etc.
Since the compressor consists of high precision components, contaminants generate scratches on the sliding
surfaces, thereby increasing gas leak, deteriorating performance, and causing excessive wear and seizure.
●Flow nitrogen gas during welding.
●Piping inside and outside must be clean.
●Avoid mixing of debris during cutting
and deburring copper pipe.
Airtight Te s t
Pressure testing should only be carried out by personal /
companies who have necessary certification.
Consider carefully local regulations and EN378.
Outer side Inner side
8MPa 8MPa
Caution for Gas Leak
Gas leak may lead to excessive heat operation of
compressor and air-mixed operation, thus causing
compressor failure.
Securely execute airtight test.
Piping Direction
The pipe can be connected from 1directions (left
side of the refrigeration unit).
When connecting the refrigerant pipe, remove the
left side panel.
Suction Filter
Be sure to install the suction filter
available as optional accessory.
Model No. S-008T
Filter Dryer
Be sure to attach the included filter dryer.
Model No. D-152T (Type: CO-082-S)
Liquid line
Suction line
Correct Incorrect
N2cylinder
Brazing position
Fill the gap with sealing material.
Open gap may cause air to be mixed.
Apply dry nitrogen gas flow
barely felt by the palm.
EN -18

ENGLISH
Piping Example
Total piping length should be limited to 50 m one way.
When the evaporator is located higher
●The suction line should ideally slope gently towards the unit.
Recommendation slope is 1/200~1/250.
●Refrigerant pipe should be covered
with heat insulation material on both
suction line and liquid line.
When the evaporator is located lower
■Height difference 20 m or below
To promote good oil return in the suction line, piping size and trap
need to be considered.
●The suction line should ideally slope gently towards the unit.
Recommendation slope is 1/200~1/250.
●Refrigerant pipe should be covered with heat insulation material
on both suction line and liquid line.
EN -19
■Height difference 5 m or below
Suction line
Liquid line
Suction line
Liquid line
Suction
Liquid
Note: Do not close air vent with suction line and liquid line
wrapped with heat insulation material.
Keep some space in air vent as described in graph.

Solid line :Refrigerant
Dotted line :Oil
EN -20
Refrigerant Circuit Diagram