NuAire NU-9728GA User manual

NU-9728GA
Ultra-Low Temperature Freezer
INSTRUCTION MANUAL

1
CONTENTS
INTRODUCTION P. 2
PRECAUTIONS FOR SAFE OPERATION P. 3
ENVIRONMENTAL CONDITIONS P. 7
FREEZER COMPONENTS P. 8
Control panel P.10
REMOTE ALARM TERMINAL P. 11
AIR INTAKE PORT P. 11
INSTALLATION SITE P. 12
INSTALLATION P. 13
START-UP OF UNIT P. 14
CHAMBER TEMPERATURE SETTING P. 15
KEY LOCK FUNCTION P. 15
ALARM TEMPERATURE SETTING P. 16
SETTING OF ALARM RESUME TIME P. 17
SETTING OF COMPRESSOR DELAY TIME P. 18
SETTING OF DOOR ALARM DELAY TIME P. 19
MONITOR OF FREEZER STATUS P. 20
ALARMS & SAFETY FUNCTIONS P. 21
ROUTINE MAINTENANCE P. 22
Cleaning of cabinet P. 22
Cleaning of condenser filter P. 22
Defrosting of inside wall P. 23
Cleaning of air intake port P. 24
TROUBLESHOOTING P. 25
DISPOSAL OF UNIT P. 26
Recycle of battery P. 26
Decontamination of unit P. 26
DISPOSAL OF BATTERY P. 27
TEMPERATURE RECORDER (OPTION) P. 28
Setting of MTR-G85C P. 28
Installation of MTR-G85C P. 29
BACKUP COOLING KIT (OPTION) P. 30
INVENTORY RACK P. 32
SPECIFICATIONS P. 33
PERFORMANCE P. 34
SAFETY CHECK SHEET P. 35

2
INTRODUCTION
Read this instruction manuals carefully before using the appliance and follow the instructions for safety
operation.
Never guarantee any safety if the appliance is used for any objects other than intended use or used by
any procedures other than those mentioned in this instruction manuals.
Keep this instruction manuals in an adequate place to refer to it as necessary.
The contents of the instruction manuals will be subjected to change without notice due to the
improvement of performance or functions.
Contact our sales representative or agent if any page of the instruction manuals is lost or page order is
incorrect.
Contact our sales representative or agent if any point in this instruction manuals is unclear or if there are
any inaccuracies.
No part of this instruction manuals may be reproduced in any form without the expressed written
permission of NUAIRE.

3
PRECAUTIONS FOR SAFE OPERATION
It is imperative that the user complies with this instruction manuals
as it contains important safety advice.
Items and procedures are described so that you can use this unit correctly and safely.
If the precautions advised are followed, this will prevent possible injury to the user and
any other person.
Precautions are illustrated in the following way:
WARNING
Failure to observe WARNING signs could result in a hazard to personnel
possibly resulting in serious injury or death.
CAUTION
Failure to observe CAUTION signs could result in injury to personnel and
damage to the unit and associated property.
Symbol shows;

this symbol means caution.

this symbol means an action is prohibited.

this symbol means an instruction must be followed.
Be sure to keep this instruction manuals in a place accessible to users of this unit.
Some warning and/or caution labels are attached on the unit. Following shows the description of such
labels.
This label is on the cover in which the electrical components of high voltage are enclosed
to prevent the electric shock. The cover should be removed by a qualified engineer or a
service personnel only.
This symbol means attention or refer to document.
This symbol means earth.
This symbol means power switch “ON”.
This symbol means power switch “OFF”.
WARNING
As with any equipment that uses CO
2
gas, there is a likelihood of oxygen depletion in the vicinity
of the equipment. It is important that you assess the work site to ensure there is suitable and
sufficient ventilation. If restricted ventilation is suspected, then other methods of ensuring a
safe environment must be considered. These may include atmosphere monitoring and
warning devices.

4
PRECAUTIONS FOR SAFE OPERATION
Do not use the unit outdoors. Current leakage or electric shock may result if the unit is exposed to
rain water.
Only qualified engineers or service personnel should install the unit. The installation by
unqualified personnel may cause electric shock or fire.
Install the unit on a sturdy floor and take an adequate precaution to prevent the unit from
turning over.
If the floor is not strong enough or the installation site is not adequate, this may result
in injury from the unit falling or tipping over.
Never install the unit in a humid place or a place where it is likely to be splashed by water.
Deterioration of the insulation may result which could cause current leakage or electric shock.
Never install the unit in a flammable or volatile location.
This may cause explosion or fire.
Never install the unit where acid or corrosive gases are present as current leakage or electric
shock may result due to corrosion.
Always ground (earth) the unit to prevent electric shock. If the power supply outlet is not
grounded, it will be necessary to install a ground by qualified engineers.
Never ground the unit through a gas pipe, water main, telephone line or lightning rod. Such
grounding may cause electric shock in the case of an incomplete circuit.
Connect the unit to a power source as indicated on the rating label attached to the unit. Use of
any other voltage or frequency other than that on the rating label may cause fire or electric shock.
Never store volatile or flammable substances in this unit if the container cannot be sealed. These
may cause explosion or fire.
Do not insert metal objects such as a pin or a wire into any vent, gap or any outlet on the unit.
This may cause electric shock or injury by accidental contact with moving parts.
Use this unit in safe area when treating the poison, harmful or radiate articles. Improper use
may cause bad effect on your health or environment.
Turn off the power switch (if provided) and disconnect the power supply to the unit prior to any
repair or maintenance
of the unit in order to prevent electric shock or injury.
Do not touch any electrical parts (such as power supply plug) or operate switches with a wet
hand.
This may cause electric shock.
WARNING

5
PRECAUTIONS FOR SAFE OPERATION
Ensure you do not inhale or consume medication or aerosols from around the unit at the time of
maintenance. These may be harmful to your health.
Never splash water directly onto the unit as this may cause electric shock or short circuit.
Never put containers with liquid on the unit as this may cause electric shock or short circuit when
the liquid is spilled.
Never bind, process, or step on the power supply cord, or never damage or break the power
supply plug.
A broken supply cord or plug may cause fire or electric shock.
Do not use the supply cord if its plug is loose.
Such supply cord may cause fire or electric shock.
Never disassemble, repair, or modify the unit yourself.
Any such work carried out by an
unauthorized person may result in fire, or electric shock or injury due to a malfunction.
Disconnect the power supply plug if there is something wrong with the unit. Continued
abnormal operation may cause electric shock or fire.
When removing the plug from the power supply outlet, grip the power supply plug, not the cord.
Pulling the cord may result in electric shock or fire by short circuit.
Disconnect the power supply plug before moving the unit. Take care not to damage the power
cord. A damaged cord may cause electric shock or fire.
Disconnect the power plug when the unit is not used for long periods. Keeping the connection
may cause electric shock, current leakage, or fire due to the deterioration of insulation.
If the unit is to be stored unused in an unsupervised area for an extended period, ensure that
children do not have access and that doors are locked completely with a key.
The disposal of the unit should be accomplished by appropriate personnel. Remove doors to
prevent accidents such as suffocation.
Do not put the packing plastic bag within reach of children as suffocation may result.
WARNING

6
PRECAUTIONS FOR SAFE OPERATION
This unit must be plug into a dedicated circuit protected by branch circuit breaker.
Use a dedicated power source as indicated on the rating label attached to the unit. A multiple-tap
may cause fire resulting from abnormal heating.
Connect the power supply plug to the power source firmly after removing the dust on the plug.
A dusty plug or improper insertion may cause a heat or ignition.
Never store corrosive substances such as acid or alkali in this unit if the container cannot be
sealed. These may cause corrosion of inner components or electric parts.
Check the setting when starting up of operation after power failure or turning off of power
switch.
The stored items may be damaged due to the change of setting.
Be careful not to tip over the unit
during movement to prevent damage or injury.
Prepare a safety check sheet (copy the last page)
when you request any repair or maintenance for
the safety of service personnel.
CAUTION

7
ENVIRONMENTAL CONDITIONS
This equipment is designed to be safe at least under the following conditions (based on the IEC61010-1):
Indoor use;
Altitude up to 2000 m;
Ambient temperature 5
o
C to 40
o
C;
Maximum relative humidity 80% for temperature up to 31
o
C decreasing linearly to 50% relative humidity
at 40
o
C;
Mains supply voltage fluctuations up to ± 10% of the nominal voltage;
Transient overvoltages up to the levels of OVERVOLTAGE CATEGORY II;
Temporary OVERVOLTAGES occurring on the mains supply;
Applicable pollution degree of the intended environment (POLUTION DEGREE 2 in most cases)

8
FREEZER COMPONENTS
11(inside)
7
1
2
3
6
8
12
7
4
9
10
13
5
18
19
17
14
20
16
Rear side
Power cord
15

9
FREEZER COMPONENTS
1. Control panel (on the upper front of the outer door): Used for temperature setting and indication
of operating status is displayed on the panel. See page 10 for details.
2.
Outer door: To open the door, grip the handle. On closing, lock the outer door latch completely.
3. Inner door: The operation of the inner door should be quick to minimize the temperature rise in
chamber. Lock the inner door latch completely when the inner door is closed. The inner door is
removable for cleaning or defrosting. See page 23 “Routine maintenance”.
4. Outer door latch: Always lock the latch when the outer door is closed.
5. Inner door latch: Always lock the inner door latch when the inner door is closed.
6. Magnetic door gasket: This provides a tight door seal and prevents cold air leak. Keep clean.
7. Access port (rear and bottom): This is used for leading a cable and sensor of a measuring
equipment, or nozzle of .backup cooling kit to chamber.
8. Air intake vent (grille):
Do not block this vent to keep the proper cooling performance.
9. Caster: Four casters are provided to facilitate moving of the cabinet. For the installation, adjust the
leveling foot so that the front two casters cannot contact with the floor.
10. Leveling foot: The height of the freezer can be adjusted by this screw type foot. Keep the unit in
level at the installation.
11. Condenser filter (behind the grille): This filter prevents the dust from accumulating on the
condenser. The dusty condenser filter may cause failure of refrigerating device. Clean the condenser
filter once a month. See page 22 “Routine maintenance” for the cleaning.
12. Space for temperature recorder: An automatic temperature recorder (optional component) can be
attached here. See page 32“ Temperature recorder (Option)”.
13. Key lock: Turn counterclockwise to 180
o
with a key and the outer door is securely locked.
14. Shelf: Use to store the materials in the freezer. It is recommended to store the items on the shelf.
The maximum load is 50 kg.
15. Air intake port: After closing the outer door, if used to open soon. See page 11
Be sure to close the cap of the air intake port after the use.
* Replace the cap when the air intake port is not used. Improper replacement may cause rise of
chamber temperature or condensation around the air intake port.
16. Fixture (on back side): Two fixtures are provided as spacers between the cabinet and wall and also
serve as hooks to fix the unit. See page 13 “Installation”.
17. Power switch:
This is for turning ON/OFF the power to the unit. ON – “I” OFF – “ ○ ”
18. Remote alarm terminal: This is used to notice an alarm condition of the unit to remote location.
Refer to page 11 “Remote alarm terminal”.
19. Battery switch: This is a switch for a battery for power failure alarm. Normally, turn on this switch.
Be sure to turn off this switch if the freezer is not in operating for the long period (over one month).
20. Fuse: AC 250 V, 5 A is attached.
WARNING
Fix the shelf supports and shelves securely. Incomplete installation may cause injury or damage. Take
care when handling shelves, as you may be injured if shelves drop on your leg. Never touch the storage
items with wet hands. Touching with the wet hands may cause frostbite. Replace the cap when the air
intake port is not used. Improper replacement may cause rise of chamber temperature or condensation
around the air intake port.

10
FREEZER COMPONENTS
Control panel
1. Digital temperature indicator: This indicator shows the present chamber temperature or set
temperature.
2. Status monitor lamp (STATUS):
This lamp lights when environmental condition or status gets worse
or the unit is out of normal operation.
3. Battery check lamp (BATTERY): This lamp lights to recommend the battery replacement. This
lamp blinks when a fan motor is replacement. For the replacement, consult our sales representative or
agent.
4. Alarm lamp (ALARM):
This lamp is flashed during alarm condition.
5. Filter check lamp (FILTER):
This lamp lights and buzzer sound when the excessive dust is
accumulated on the condenser filter. When this lamp lights, clean the condenser filter following the
procedure on page 22.
6. Numerical value shift key ( ):
Pressing this key in the setting mode causes the numerical value to
shift. “ON-OFF” of key lock can be selected by pressing this key in the key lock setting mode. By
pressing this key for more than 5 seconds in the temperature display mode leads setting mode for alarm
temperature, alarm resume time ,compressor delay time and door alarm delay time. Refer to page 15,
16,17,19 and 20 for details respectively.
7. Digit shift key ( ):
Pressing this key in the setting mode causes the changeable digit to shift. Key
lock setting is available by pressing this key for more than 5 seconds in the temperature display mode.
Refer to page 15 for details.
8. Set key (SET):
Temperature setting mode is led by pressing this key and the changeable digit is
flashed. By pressing this key again, the setting is memorized. The setting mode returns to the
temperature display mode automatically when 90 seconds has passed without any key operation.
9. Status key (STATUS):
By pressing this key in the event of the status monitor lamp ON, the status
code is displayed on the digital temperature indicator. This key is not effective when the freezer is
running normally. See page 18 for details.
10. Alarm test key (ALARM TEST):
To check the alarm system during freezer operation. Pressing
this key with the battery switch ON gets the alarm lamp to flash, the remote alarm to operate, and the
buzzer to sound.
11. Buzzer stop key (BUZZER): To silence the audible alarm under alarm condition, press this key.
The buzzer during alarm test cannot be silenced by this key. But the remote alarm is not canceled.
12. Door check lamp (DOOR): This lamp lights when the outer door is open.
11 10 9 8 7 6
1 3 2 54
12

11
REMOTE ALARM TERMINAL
The terminal of the remote alarm is installed at the lower left side of the unit. The alarm is outputted from
this terminal. Contact capacity is DC 30 V, 2 A.
Contact output: between COM. and N.O. between COM. and N.C.
At normal Open Close
At abnormal Close Open
Note:
• The buzzer is silenced by pressing buzzer stop key (BUZZER) on the control panel during alarm
condition. (A remote alarm is continuing the operation.)
The buzzer will be activated again after certain suspension if the alarm condition is continued.
• The alarm is actuated when the power supply plug is disconnected from the outlet or the power switch is
OFF.
AIR INTAKE PORT
When a door is closed and opened soon, a door does not
sometimes open this product.
The warm air which went into the chamber is cooled down rapidly,
and this is because air inside the chamber contracted.
When a door is closed and opened soon, a door is easy to open
with the following process.
1. Turn the cap of the left side counterclockwise about two laps.
(That can be removed completely)
2. Put the air into the chamber from about twenty seconds, and
open a door.
3. Close a cap if a door opens.
A door may not open in the above method when there are frost and ice in the air intake port. In that case,
open a cap, and investigate the matter whether there is no frost inside the air intake port. Remove frost
inside the air intake port in "the air intake port cleaning stick" of the accessories when there is frost.
Clean a air intake port every month even when there is no frost inside the air intake port. Refer to page
24.
WARNING
For removing the frost of the air intake port, do not use a tool with sharp edge such as a knife or a screw
driver.
Replace the cap when the air intake port is not used. Improper replacement may cause rise of chamber
temperature or condensation around the air intake port.
Cap
Two laps

12
INSTALLATION SITE
To operate this unit properly and to obtain maximum performance, install the unit in a location with the
following conditions:
A location not subjected to direct sunlight
Do not install the unit under direct sunlight. Installation in a location subjected to direct sunlight cannot
obtain the intended performance.
A location with adequate ventilation
Leave at least 10 cm around the unit for ventilation. Poor ventilation will result in a reduction of the
performance and consequently the failure.
A location away from heat generating sources
Avoid installing the unit near heat-emitting appliances such as a heater or a boiler etc. Heat can
decrease the intended performance of the unit.
A location with little temperature change
Install the unit under stable ambient temperature. The allowable ambient temperature is between +5 and
+30
o
C.
A location with a sturdy and level floor
Always install the unit on a sturdy and level floor. The uneven floor or tilted installation may cause failure
or injury. Install the unit in stable condition to avoid the vibration or noise. Unstable condition may
cause vibration or noise.
WARNING
Install the unit on a sturdy floor. If the floor is not strong enough or the installation site is not adequate,
this may result in injury from the unit falling or tipping over.
Select a level and sturdy floor for installation.
This precaution will prevent the unit from tipping.
Improper installation may result in water spillage or injury from the unit tipping over.
A location not prone to high humidity
Install the unit in the ambient of 80% R.H. or less humidity. Installation under high humidity may cause
current leakage or electric shock.
WARNING
Do not use the unit outdoors.
Current leakage or electric shock may result if the unit is exposed to rain
water.
Never install the unit in a humid place or a place where it is likely to be splashed by water.
Deterioration of the insulation may result which could cause current leakage or electric shock.
A location without flammable or volatile gas
Never install the unit in a flammable or volatile location. This may cause explosion or fire or may result in
the current leakage or electric shock by the corrosion of the electrical components.
A location without the possibility of anything fall
Avoid installing the unit in the location where anything can fall down onto the unit. This may cause the
breakdown or failure of the unit.
Wire gage to the outlet from distribution box
The recommended wire gage to the outlet from distribution box (breaker box from electrical supply to
receptacle unit is plugged into) is dependant on *length of wire*, the following information is a good rule of
thumb to follow:
・ 60ft or less 12ga
・ 60ft - 100ft 10ga
・ 100ft - 150 ft 8ga
・ 150ft - 250ft 6ga

13
INSTALLATION
1. Removing the packaging materials and tapes
Remove all transportation packaging materials and tapes. Open the doors and ventilate the unit. If the
outside panels are dirty, clean them with a diluted neutral dishwashing detergent. (Undiluted detergent
can damage the plastic components. For the dilution, refer to the instruction of the detergent.) After the
cleaning with the diluted detergent, always wipe it off with a wet cloth. Then wipe off the panels with a dry
cloth.
Note:
Remove the cable tie banding the power supply cord.
Prolonged banding may cause the corrosion of the
cord coating.
2.
Adjusting the leveling foot
Extend the leveling feet by rotating them
counterclockwise to contact them to the floor.
Ensure the unit is level. (Fig. 1)
3.
Fixing the unit
Two fixtures are attached to the rear of the frame.
Fix the frame to the wall with these fixtures and rope
or chain. (Fig. 2)
4. Power source
For stable and reliable cooling operation, check the
following items before connecting the freezer to a
power source. (Fig. 3)
Voltage of the power source: 115 V, 60 Hz
Receptacle of the power source: NEMA reference
5-20R
(The equipment has a NEMA 5-20P plug.)
If not, it is necessary to install 5-20R receptacle by
qualified engineers.
Current capacity of the power source: 20 amperes
Rating amperage of the circuit breaker or fuse used in
the power line: 20 amperes
(Use item delay type in case of fuse.)
Do not connect the other equipment
5.
Ground (earth)
The ground (earth) is for preventing the electric shock in the case of the electrical insulation is somehow
degraded. Always ground the unit at the time of installation.
WARNING
Use a power supply outlet with ground (earth) to prevent electric shock. If the power supply outlet is
not grounded, it is necessary to install a ground by qualified engineers.
Never ground the unit through a gas pipe, water main, telephone line or lightning rod. Such
grounding may cause electric shock in the case of an incomplete circuit.
6. Installing the earth leakage breakers
This product is to connect a earth leakage breaker to the power supply side of the product.
Contact our sales representative or agent at the time of installation of the earth leakage breaker.
Leveling foot Fig.1
Fixture Fig. 2
Fig. 3
5-20P 5-20R

14
START-UP OF UNIT
Follow the procedures for the initial and consequent operations of the unit.
1.
Turn off the switch of the .backup cooling kit (optional component) if it is installed.
2. Connect the power supply cord to the dedicated outlet having appropriate rating with the chamber
empty, and turn on the power switch on the freezer.
3.
Turn on the battery switch.
4. Set the desired chamber temperature. See page 15 for the chamber temperature setting.
5. Check that the chamber temperature reaches the desired temperature.
6.
Turn on the switch of .backup cooling kit (optional component) if it is installed.
7. Make sure that the alarm lamp blinks and the buzzer sounds by pressing the alarm test key (ALARM
TEST). The remote alarm is also operated. E09 is displayed on the digital temperature indicator if the
battery switch is OFF. Make sure to turn on the battery switch.
8. After confirming the above, you can put articles into the chamber in a small batch to prevent the
temperature rise.
CAUTION
Do not put too many warm articles in the chamber. The temperature rise may cause the damage
to the articles in the chamber.
WARNING
Fix the shelf supports and shelves securely. Incomplete installation may cause injury or damage.
Operation after power failure
The set value is memorized by nonvolatile memory. Accordingly, the freezer resumes the operation with
setting before power failure.
When the freezer is recovered from power failure with the chamber temperature higher than the preset
temperature, then the high temperature alarm is activated and the buzzer sounds and the remote alarm is
also activated. Push the buzzer stop key (BUZZER) to silence buzzer and take appropriate actions if
needed.
WARNING
When this product operates at the first start-up or after no use for long period, the built-in battery capacity
may be lowered or completely zero because of discharge of the battery. After installation the product, the
freezer should operate for more than 3 days (72 hours) to charge the battery.
Note:
When the power is turned on, it may take 30 up to 60 minutes (depending on the ambient temperature) to
start the compressor in order to reduce stress after being idle for extended periods of time.
This is an intended operation therefore please keep the power on until the freezer actually starts
running.

15
CHAMBER TEMPERATURE SETTING
Table 1 shows the basic procedure for setting the chamber temperature. Perform key operations in the
sequence indicated in the table. The example in the table is based on the assumption that the desired
temperature is -75
o
C.
Note: The unit is set at the factory that the chamber temperature -80
o
C.
Table 1. Basic operation sequence (Example: Chamber temperature -75
o
C)
Description of operation Key operated Indication after operation
1 Turn the power switch ON.
---- The current chamber temperature is
displayed.
2 Press set key. SET The second digit is flashed.
3 Set to -75 with the numerical value
shift key and digit shift key.
When pressed, the figure of settable
digit changes.
When pressed, the settable digit
is shifted.
4 Press set key. SET Set temperature is memorized and the current chamber temperature is
displayed.
Note:
• Although the value of the chamber temperature setting can range from -50
o
C to -90
o
C, the guaranteed
temperature when there is no load is -86
o
C when the ambient temperature is 30
o
C.
• The setting mode returns to the temperature display mode automatically when 90 seconds has passed
without any key operation. In this case, any setting before pressing set key (SET) is not memorized.
KEY LOCK FUNCTION
This unit is provided with the key lock function. When the key lock is ON, change of temperature setting
through the key pad is not available. The key lock is set in OFF at the factory.
Display Mode Function
L 0 Key lock is OFF Enable to change of temperature setting
L 1 Key lock is ON Disable to change of temperature setting
Table 2. Procedure for key lock setting (change from key lock OFF to key lock ON)
Description of operation Key operated Indication after operation
1 ---- The current chamber temperature is
displayed.
2 Press digit shift key for 5 seconds.
The first digit is flashed.
3 Press numerical value shift key
and scroll the figure to 1. When pressed, the figure of settable
digit changes.
4 Press set key. SET The key lock is set to ON. The current chamber temperature is
displayed.
• The setting mode returns to the temperature display mode automatically when 90 seconds has passed
without any key operation.

16
ALARM TEMPERATURE SETTING
This unit is provided with the high and low temperature alarm and the temperature at which the alarm is
activated is changeable.
The following procedure shows the setting of alarm temperature according to the condition below:
High temperature alarm: activates at the temperature 5
o
C higher than the set temperature
Low temperature alarm: activates at the temperature 5
o
C lower than the set temperature
Note:
The alarm temperature is set at the factory 10
o
C higher and lower than the set temperature.
The available range of alarm temperature is between 5
o
C and 40
o
C higher or lower than the set
temperature.
Table 3. Procedure for setting high temperature alarm
Description of operation Key operated Indication after operation
1 ---- The current chamber temperature is
displayed.
2 Press numerical value shift key for
about 5 seconds. The first digit is flashed.
3 Press numerical value shift key
and scroll the figure to 1. When pressed, the figure of settable
digit change.
4 Press set key. SET The current setting is displayed and
the first digit is flashed.
5 Scroll the figure to 005 by using digit shift key and numerical value
shift key
When pressed, the figure of settable digit changes.
When pressed, the changeable digit
is shifted.
6 Press set key. SET Alarm temperature is memorized and the current chamber temperature is
displayed.
Table 4. Procedure for setting low temperature alarm
Description of operation Key operated Indication after operation
1 ---- The current chamber temperature is
displayed.
2 Press numerical value shift key for
about 5 seconds. The first digit is flashed.
3 Press numerical value shift key
and scroll the figure to 2. When pressed, the figure of settable
digit change.
4 Press set key. SET The current setting is displayed and
the first digit is flashed.
5 Scroll the figure to -05 by using digit shift key and numerical value
shift key
When pressed, the figure of settable digit changes.
When pressed, the changeable digit
is shifted.
6 Press set key. SET Alarm temperature is memorized and the current chamber temperature is
displayed.
• The setting mode returns to the temperature display mode automatically when 90 seconds has passed
without any key operation.

17
SETTING OF ALARM RESUME TIME
The alarm buzzer is silenced by pressing alarm buzzer stop key (BUZZER) on the control panel during
alarm condition. (A remote alarm is continuing the operation.).
The buzzer will be activated again after certain suspension if the alarm condition is continued. The
suspension time can be set by following the procedure shown in the Table 5 below.
The example in the table is based on the assumption that the desired duration is 20 minutes.
Note: The duration is set in 30 minutes at the factory.
Table 5. Setting procedure for alarm resuming time (change from 30 minutes to 20 minutes)
Description of operation Key operated Indication after operation
1 ---- The current chamber temperature is
displayed.
2 Press digit shift key for 5 seconds.
The first digit is flashed.
3 Set the figure to F25 with the digit
shift key and numerical value shift
key.
The settable digit is shifted.
When pressed, the figure of settable
digit changes.
4 Press set key. SET The current resume time is displayed.
The second digit is flashed.
5 Scroll the figure to 020 with the
numerical value shift key. When pressed, the figure of settable digit changes.
6 Press set key. SET The setting is memorized and
the current chamber temperature is
displayed.
• The settable alarm resume time is 10, 20, 30, 40, 50, or 60 minutes (The setting is 010, 020, 030, 040,
050, or 060). The buzzer would not resume if the resume time is set in 000.
• It is recommended to set the alarm resume time when the freezer is not under alarm condition. The
setting during alarm condition is effective on the next alarm condition.
• The setting cannot be changed during power failure.
• The setting mode returns to the temperature display mode automatically when 90 seconds has passed
without any key operation.

18
SETTING OF COMPRESSOR DELAY TIME
The delay time of high and low stage side compressor can be changed to reduce the load on the power
line and to facilitate the start-up (reset) of the freezer after power failure.
The example in the table 6 is based on the assumption that the delay time is changed to 4 minutes.
(The delay time is set in 3 minutes at the factory.)
Note:
• The delay time should be the same for high stage side and low stage side compressors.
• The setting range for delay time is between 3 and 15 minutes. The cool down of chamber temperature
may be slow when the setting of delay time is over 5 minutes, depending on the installation environment.
There is no need of changing the delay time when the capacity of power source is adequate.
Table 6. Setting procedure for delay time (change from 3 minutes to 4 minutes)
Description of operation Key operated Indication after operation
1 ---- The current chamber temperature is
displayed.
2 Press numerical value shift key for
5 seconds. The first digit is flashed.
3 Set the figure to F05 with the
numerical value shift key. When pressed, the figure of settable
digit changes.
4 Press set key. SET The current delay time is displayed.
The first digit is flashed.
5 Set the figure to 004 with the
numerical value shift key. When pressed, the figure of the first digit changes.
6 Press set key. SET The delay time is memorized and
the current chamber temperature is
displayed.
• The compressor starts to operate with the delay time set by the above procedure at the time of power on
or after power failure. However, the start up of the low stage side compressor is affected by the chamber
temperature and the cascade condenser temperature. The delay time varies depending on how they
meet the start up conditions. It is more than four minutes in case of the above example.
• The setting mode returns to the temperature display mode automatically when 90 seconds has passed
without any key operation.

19
SETTING OF DOOR ALARM DELAY TIME
The buzzer of door alarm is activated with 2 minutes delay when the outer door is open. The delay time
is changeable.
Follow the procedure in table 7 below to change the setting of delay time. The procedure assumes that
the delay time is changed from 2 minutes to 3 minutes.
(The delay time is set in 2 minutes at the factory.)
Table 7. Setting procedure for delay time (change from 2 minutes to 3 minutes)
Description of operation Key operated Indication after operation
1 ---- The current chamber temperature is
displayed.
2 Press numerical value shift key for
5 seconds. The first digit is flashed.
3 Set the figure to F04 with the
numerical value shift key. When pressed, the figure of settable
digit changes.
4 Press set key. SET The current delay time is displayed.
The first digit is flashed.
5 Set the figure to 003 with the
numerical value shift key. When pressed, the figure of the first
digit changes.
6 Press set key. SET The delay time is memorized and the current chamber temperature is
displayed.
Note:
• The setting range for delay time is between 1 and 15 minutes.
• The setting mode returns to the temperature display mode automatically when 90 seconds has passed
without any key operation.