Thermo Scientific Harris MBF-700 User manual

Installation and Operation Manual
Thermo Scientific®Harris MBF-700
Refrigeration System

©20 Thermo Fisher Scientific. All rights reserved.
“Suva®” is a registered trademark of DuPont.
All other trademarks are the property of Thermo Fisher Scientific Inc. and
its subsidiaries.

Table of Contents
Thermo Fisher Scientific Generic MBF700 Service Manual i
Table of Contents
Section 100 – Product Introduction .............................................. 1
Freezer Overview ........................................................................... 1
General Construction .................................................................... 2
Control Panel ............................................................................... 3
Liquid CO2 (LCO2) Backup System .......................................... 4
Section 200 – Installation And Operation ..................................... 17
Installation Check List ................................................................... 17
Operator's Responsibilities ............................................................ 17
Water-cooled Condensing Unit Connections ............................. 19
Cleaning The Freezer Surfaces ....................................................... 21
Storage .......................................................................................... 21
Section 300 – Theory Of Operation .............................................. 22
Overview ....................................................................................... 22
Sequence Of Operation ................................................................. 22
Systems Description ...................................................................... 23
Refrigeration Systems .................................................................. 23
Safety Devices ............................................................................. 24
Temperature Control .................................................................. 24
LCO2 Backup System ................................................................ 25
Halo Passes ................................................................................. 26
Operation ...................................................................................... 26
Cascade Refrigeration System ..................................................... 26
Main Temperature Control ........................................................ 27
Backup Temperature Control System ......................................... 29
Section 400 – Maintenance And Service ........................................ 31
Preventive Maintenance Procedures .............................................. 31
Air Cooled Condensers ............................................................... 31
Compressor Oil Level ................................................................. 31
fan Motors .................................................................................. 31
Defrosting ................................................................................... 31

Table of Contents
ii Generic MBF700 Service Manual Thermo Fisher Scientific
LCO2 Vent ................................................................................ 32
Trouble Shooting Guide ............................................................... 32
Contactors And Relays ................................................................ 39
Compressor Motors, Three Phase ............................................... 39
Partial Or Complete Loss Of Refrigeration ................................. 40
Checking Refrigerant Charge ...................................................... 40
Installing Gauges ........................................................................ 41
Leak Testing, Repairing And Charging – An Overview ............... 41
Repair Procedures .......................................................................... 43
Compressor Replacement ............................................................ 43
Backflush Procedure ................................................................... 46
Evacuation Procedure ................................................................. 48
Charging Procedure -- 1st (High) Stage ...................................... 51
Charging Procedure -- 2nd (Low) Stage ...................................... 51
Thermocouple Labeling And Locations ...................................... 53
temperature Calibration .............................................................. 53
Section 500 – Appendix ................................................................ 55
Refrigeration System Data ............................................................ 56
Service Parts List ........................................................................... 57

SECTION 100 – PRODUCT INTRODUCTION
Thermo Fisher Scientific Generic MBF700 Service Manual 1
SECTION 100 –
PRODUCT
INTRODUCTION
FREEZER OVERVIEW This unit is a low temperature freezer designed to operate with a chamber
temperature in the range of –65 to –85 °C (-85 to –121 °F) and in an
ambient temperature range of 15 to 32 °C (59 to 89.6 °F).
The cabinet configuration is that of a rectangular solid measuring 121” long
(3 07.3cm) x 47.5” high (120.7cm) with lid and all covers in place x
35.312” deep (89.7cm). When installing the freezer, a minimum of six
inches (6”) must be provided on all sides of the freezer for proper air
circulation.
Weight is 1510 lbs. (684.8Kg) net.
Shipping weight is 1790 lbs (811.8Kg).
Power Requirements: 208V - 230VAC, 3 Phase , 60Hz
120VAC, 1 , 60Hz (LCO2 backup system)
Figure 1. General Freezer Outline (see Figure 3 for control panel
details)
The interior useable space is also rectangular. The four corners are coved.
With insulating sub lids in place it measures 71” long (180.3cm)x 35.37”
high (89.9cm) x 22.63” deep (57.5cm). The interior volume is 31 Ft.
(878.7 liters.)
The cabinet is insulated with nominal 5” of foamed-in-place polyurethane
insulation.

SECTION 100 – PRODUCT INTRODUCTION
2Generic MBF700 Service Manual Thermo Fisher Scientific
CAUTION Do not discard the sub lids. They are necessary for the
operation of the unit.
The refrigeration arrangement employed in this freezer is a specially
designed assembly using four hermetic motor compressors. This design is
termed a “redundant cascade system”. A more complete description of this is
in the pages following. Stainless steel storage racks for inventory control are
avaiable as an option and must be ordered separately.
GENERAL
CONSTRUCTION The lid is held tightly closed by means of cam locks having provision for a
user supplied padlock.
Durable corrosion protection is provided by an electrostatically applied
epoxy fused powder coating over cold rolled steel.
To provide a redundant refrigeration system, the inner tank is double
wrapped with copper tubing forming a dual circuit evaporator. In addition,
each of these circuits has its own compressor, condenser and liquid
refrigerant control (capillary tube). Each of the redundant systems will
support full operation to maintain the storage temperature. When set to
alternate between system “A” and system “B”, refrigeration is applied to the
freezer chamber alternating between systems on each cycle.
Figure 2. Cabinet Dimensional Drawing

SECTION 100 – PRODUCT INTRODUCTION
Thermo Fisher Scientific Generic MBF700 Service Manual 3
CONTROL PANEL All controls are located at the right end of the cabinet
Figure 3. Control Panel Detail
1. Key-operated alarm ON/OFF switch. Turns on local audio alarm.
2. Key-operated compressor ON/OFF switch. Turns on power to
compressors and control system.
3. Digital temperature indicator and primary control
4. Temperature recorder, 7-day, 6” diameter.
5. System “B” indicator light. “ON” when system “B” 1st stage
running.
6. System “A” indicator light. “ON” when system “A” 1st stage
running.

SECTION 100 – PRODUCT INTRODUCTION
4Generic MBF700 Service Manual Thermo Fisher Scientific
7. Alternate system alarm indicator light. “ON” when auxiliary control
causing both systems to operate.
8. Heater switch. Operates breaker strip condensate heater.
9. Battery meter. Displays state of battery charge when button is
pressed.
The remote alarm contacts were developed to provide an alert for an alarm
condition. The remote alarm contacts are normally closed, and open during
an alarm event. The contacts are rated for a maximum of 36V3A
LIQUID CO2 (LCO2)
BACKUP SYSTEM When connected to a user supplied siphon tank of liquid CO2, the backup system will provide a source of backup refrigeration in case of power failure
to the mechanical refrigeration equipment. The control assembly operates
on 1 20VAC, 1, 60Hz. A backup battery supply is continuously charging for
operation of the backup system during power failure.
Installation
1. Place the LCO2 control system on top of the System B mechanical
section.
2. Connect the LCO2 supply to the back of the control system.
3. Connect theLCO2 distribution tube to the back of the unit.
4. Connect the LCO2 temperature sensor to the Mate-N-Loc
connector that hangs from the rear of System B mechanical section.
5. Connect the LCO2 control system harness to the Mate-N-Loc
connector that hangs from the rear of System B mechanical section.
6. The assembly of the LCO2 to the cabinet is now complete.
Note An LCO2 supply must be provided by the customer. The supply
pressure must be 900 – 1,000 PSIG.

SECTION 100 – PRODUCT INTRODUCTION
Thermo Fisher Scientific Generic MBF700 Service Manual 5
7. Uncoil the tubing from the control unit and connect to the LCO2
tank or supply connection.
8. Turn on the LCO2 valve.
9. Refer to the Backup System Owners Manual for operation
instructions.
Note LCO2 backup systems are typically built with a relief valve set for
1,300 PSIG.
LCO2 Control System Battery Condition
The charge level light illuminates when the battery is below 80% of full
charge. It is also possible that the charge level light will illuminate when the
control system is dispensing LCO2.
Placing LCO2 control system in storage
CAUTION Any rise in temperature will cause a rapid rise of pressure of
liquid CO2 trapped in the supply line. After turning off the LCO2 supply,
bleed the supply line by lowering the LCO2 setpoint sufficiently to cause
the LCO2 solenoid to open. With the solenoid open, disconnect the supply
line from the backup system control unit.
After disconnecting the LCO2 supply line, set the LCO2 control to +50 oC
and plug the unit into the power supply. This will keep the battery charged
and prevent the solenoid from operating.
LIQUID CO2BACKUP REFRIGERATION
This accessory, when connected to a user supplied siphon tank of liquid
CO2, will provide a source of backup refrigeration in case of power failure to
the mechanical refrigeration equipment. The control assembly for this
accessory operates over a range of 200VAC to 240VAC, 10, either 50Hz or
60Hz. There is a continuous charging battery backup power supply for
operation of the accessory during power failure.
Installation:
1. Place the LCO2 control system on top of the System B mechanical
section.

SECTION 100 – PRODUCT INTRODUCTION
6Generic MBF700 Service Manual Thermo Fisher Scientific
2. Place the CO2control system on top of the freezer lid.
3. Locate the switch hole in the left hand side of the right hand
machine compartment cover and remove the cover plate that was
factory installed.
4. Remove the machine compartment cover by locating and removing
the screws at the back and at front securing the cover to the housing.
5. Locate the lid switch in the accessory kit.
6. Locate the leads from the control unit with two-prong connector.
Feed the leads through the hole provided in the back of the unit,
route through machinery compartment to the left front and up
through the second hole provided. Then feed the leads through the
switch hole provided in the machinery compartment cover and
connect to the switch terminals. Snap the switch into the hole
making sure that the curved side of the plunger is on the bottom
side.
7. Replace the machinery compartment cover securing with the screws
front and back.
8. Identify the CO2discharge and control assembly mounted in the
perforated housing.
9. Remove the coiled control bulb and the CO2discharge tube from
the housing, insert the bulb through the rear cabinet porthole and
reassemble the bulb to the housing inside the cabinet. Mount the
housing to the right inside wall of the cabinet using two of the three
factory installed screws. Route the CO2discharge tube through the
porthole and, after loosening the screws securing the rear breaker
strip, slide the discharge tube under the retainer strip and re-tighten
the screws.
10. The assembly of the CO2to the cabinet is now complete.

SECTION 100 – PRODUCT INTRODUCTION
Thermo Fisher Scientific Generic MBF700 Service Manual 7
Note An uninsulated CO2supply cylinder with siphon tube must be
provided by the customer. The siphon tube allows liquid CO2to be drawn
from the cylinder. The supply pressure must be between 600 and 1050 psig.
The supply temperature must be between 7 oC and 31 oC (45 oF and 88
oF). DO NOT INSTALL A PRESSURE REGULATOR BETWEEN THE
CYLINDER AND THE CONTROL UNIT. If you are unfamiliar with
handling compressed gases, refer to a qualified service technician.
11. Uncoil the tubing from the control unit and connect to the CO2
tank or supply connection.
12. Turn on the CO2valve.
13. Adjust the temperature setpoint to the coldest position.
14. Connect the power cord of the control unit to the voltage source
indicated on the unit serial plate.
15. Open and close the freezer lid to insure that the CO2dispenses into
the freezer when the lid is closed and does not dispense when the lid
is open. If there is no discharge, check to see that the wires are
fastened securely to the lid switch and that the switch plunger is
actually depressed.
16. Set the temperature control at a minimum of 5 °C warmer than the
operating temperature of the freezer but never colder than -70 °C.
Setting colder than -70 °C will result in a continuous dispensing of
the CO2supply.
CO2Control System Battery Condition:
The charge level light comes ON when the battery is below 80% of full
charge. It is also possible that the charge level light will come on when the
control system is dispensing CO2.
When placing the control unit in storage, set the CO2control to +50 °C and
plug the unit into the power supply. This will keep the battery charge and
prevent the solenoid from operating. The capillary tube leading from the
control unit to the control bulb may be coiled up for storage but do not
make coils any smaller than 4 inch diameter. There are two screws provided

SECTION 100 – PRODUCT INTRODUCTION
8Generic MBF700 Service Manual Thermo Fisher Scientific
in the back of the control cabinet that match the slots in the back of the
control bulb housing. Slip the slots in the housing under the screw heads
and tighten. This will hold the housing and bulb securely to prevent
damage.
CAUTION Do not turn off the CO2 supply trapping liquid in the supply
line. Any rise in temperature will cause a rapid rise of pressure that will
rupture the protective disk in the control unit.
Figure 4. CO2 Backup System
COBEX ELECTRONIC, 7-DAY CIRCULAR CHART
TEMPERATURE RECORDER
This product includes a manufacturer-installed electronic temperature
recorder. These instructions are provided to assist with the initial set-up,
operation and general maintenance of the recorder.

SECTION 100 – PRODUCT INTRODUCTION
Thermo Fisher Scientific Generic MBF700 Service Manual 9
Setup and Operation
The recorder has been factory-installed, programmed, and calibrated for
your new system. Operation will begin when the system is powered on. To
prepare the recorder to function properly, you should perform the following
steps:
1. Review figure below to become familiar with recorder features.
2. Open recorder door to access recorder.
3. For back-up power, connect the 9 volt DC battery located at the
recorder’s upper right hand corner.
4. Install clean chart paper (refer to Changing Chart Paper,below).
5. Remove plastic cap from pen stylus (ink or pressure sensitive) and
close recorder door.
Note Recorder may not respond until the system reaches temperatures
within the recorder’s range.
This should complete operator setup. Additional information is provided
for maintenance and troubleshooting as required.
MAINTENANCE
CobexRecorder Face

SECTION 100 – PRODUCT INTRODUCTION
10 Generic MBF700 Service Manual Thermo Fisher Scientific
Power Supply
The recorder normally operates with AC power when the system is
operating. If AC power fails the LED indicator flashes to alert you to a
power failure. The recorder will continue sensing cabinet temperature and
the chart will continue turning for approximately 24 hours with back-up
power provided by the 9 volt battery. Both the battery and main power are
O.K. when the LED indicator glows continuously.
Changing Chart Paper
Locate the pressure sensitive buttons at the front, upper left of the recorder
panel. Press and hold the change chart button (#3) for 1 second. Pen will
move off scale. Unscrew center nut, remove old chart paper, and install new
chart paper. Carefully align the day and time with the reference mark on the
recorder panel. Replace center nut and hand tighten. Press the change chart
button (#3) again to resume temperature recording.
Changing Marker Pen
For recorders having a marker pen rather than a stylus for pressure-sensitive
paper, the pen provided is a fiber-tipped cartridge type, and is attached to
the pen arm. As the pen ink supply runs out, the pen color will become
lighter indicating the pen should be replaced. To install a new pen, loosen
the (2) screws at the top of the arm. Slip the pen cartridge out and remove
the “U” shaped clip tab from the pen. Discard the old pen. Insert the clip
tab into a new pen and then re-fasten to the pen arm.
Changing Temperature Range Program
This recorder is capable of operating in multiple pre-programmed
temperature ranges. The correct temperature range program was selected
upon factory installation and is retained even during power interruptions. If
the temperature range is wrong for any reason, it can be easily
reprogrammed as follows:
• Press change chart button #3. Pen arm will move off scale, LED will
glow continuously.
• Press and hold button #1 for 5 seconds. LED indicator will begin
flashing.
• The number of flashes corresponds to the temperature range program as
follows:

SECTION 100 – PRODUCT INTRODUCTION
Thermo Fisher Scientific Generic MBF700 Service Manual 11
Change program to the “-115 °C to +50°C” temperature range by using the
left (#1) button to increase and the right (#2) button to decrease the number
of flashes. Press the change chart button (#3) when the desired program is
set. Pen will move to the outer edge of the chart for 5 seconds. After 5
seconds, the LED indicator will glow continuously and the pen arm will
move to begin recording temperature.
Calibration
Note The pen does not begin to move until the button is held for 5 seconds.
This recorder has been accurately calibrated at the factory and retains
calibration even during power interruptions. If required, however,
adjustments can be made as follows:
1. Run unit continuously at bottom-out temperature. Continue steady
operation at least 30 minutes to provide adequate time for recorder
response.
2. Measures cabinet center air temperature with a calibrated
temperature monitor.
3. Compare recorder temperature to center air temperature. If
necessary, adjust recorder by pressing the left (#1) and right (#2)
chart buttons.
No. of Flashes Temperature Range Application Option #
1 -40 to +25°C Refrigerators 6*83-7*
2 -115 to+50°C ULT’s 6*83-6*
3 -200 to 0°C Cryogenic 6*83-5*
4 0 to +60 Newer Units Only

SECTION 100 – PRODUCT INTRODUCTION
12 Generic MBF700 Service Manual Thermo Fisher Scientific
COBEX RECORDER TROUBLESHOOTING GUIDE
LED Flashing Low Battery
Replace with a FRESH 9v alkaline battery. Battery must be
new.
No AC Power
1. Remove battery.
2. If LED goes out, then no power is getting to the unit.
3. Check power and transformer connections.
Transformer secondary is approximately 1 5v AC.
4. Be sure transformer is wired for proper voltage.
LED Out or
Unit “Dead”
Possible bad Board
1. Remove battery.
2. Disconnect or turn off power.
3. Restore power.
4. Reconnect battery.
5. Return entire unit if not working.
Wrong Range
1. Push #3 “Chart Change”.
2. With pen off chart, hold #1 for 7 seconds.
3. Release. ( Note : No range recall).
4. Green LED Flashes.
5. Push #1 or #2 to change:
• 1 flash -40 to +25C
• flashes -115 to+50C
• flashes -200 to 0C
• flashes 0 to +60C (newer units only)
6. Push #3 again.

SECTION 100 – PRODUCT INTRODUCTION
Thermo Fisher Scientific Generic MBF700 Service Manual 13
Not Calibrated Calibrate Recorder
1. Push #3. Pen comes off chart.
2. Push #3 again. Pen stops briefly on returning to
chart. Stopping point should be at edge of chart. If
not perform the following:
3. Be sure pen arm is aligned with pen arm bracket. If
not, loosen screws a adjust. During stopping interval
adjust pen arm using #1 and #2 to align pen arm with
edge of chart.
4. Place probe in cold water for 5 min. Slow response.
5. Measure the water temperature with a thermometer.
6. Adjust calibration using #1 and #2 to make recorder
read same temperature as thermometer.
7. Put probe back into solution.
8. Wait 5 minutes and adjust to cabinet temperature.
Bad Probe
1. Check probe connections
• Red wire connected to J6 pin 1
• Both black wires to J6 pin 2
2. Measure voltage across J6 approximate voltages are as
follows:
• -150C=35mv
• -85C=75mv
• -30C=1 00mv
• 3.5C=1 10mv
• 25C = 120mv (ambient)
• Probe open circuit 1 .23v (approximately)
• Probe short circuit = 0.0v (recorder possibly) faulty.
Replace probe. If still 0.0v return/replace recorder.
• >2.0v = Replace recorder and probe.
If probe voltage is off by more than a factor of 2 then probe
is faulty.
Possible bad Board
1. Remove battery.
2. Disconnect or turn off power.
3. Restore power.
4. Reconnect battery.
5. Return entire unit if not working.

SECTION 100 – PRODUCT INTRODUCTION
14 Generic MBF700 Service Manual Thermo Fisher Scientific
Pen Goes to
Center
Wrong Range
1. Momentarily depress button #3 (“Chart Change”
button).
2. With pen off chart, hold #1 for 7 seconds.
3. Release. (Note: No range recall).
4. Green LED Flashes.
5. Momentarily depress #1 or #2 to change:
• 1 flash -40 to +25C
• 2 flashes -115 to+50C
• 3 flashes -200 to 0C
• 4 flashes 0 to +60C (newer units only)
6. Momentarily depress “Chart Change” button again.
7. Not calibrated (see below)
Not Calibrated Calibrate Recorder
1. Push #3. Pen comes off chart.
2. Push #3 again. Pen stops briefly on returning to
chart. Stopping point should be at edge of chart. If
not perform the following:
3. Be sure pen arm is aligned with pen arm bracket. If
not, loosen screws a adjust. During stopping interval
adjust pen arm using #1 and #2 to align pen arm with
edge of chart.
4. Place probe in cold water for 5 min. Slow response.
5. Measure the water temperature with a thermometer.
6. Adjust calibration using #1 and #2 to make recorder
read same temperature as thermometer.
7. Put probe back into solution.
8. Wait 5 minutes and adjust to cabinet temperature.
Bad Probe
1. Check probe connections
• Red wire connected to J6 pin 1
• Both black wires to J6 pin 2
2. Measure voltage across J6 approximate voltages are as
follows:
• -150C=35mv
• -85C = 75mv
• -30C=100mv
• 3.5C=110mv
• 25C = 120mv (ambient)
• Probe open circuit 1 .23v (approximately)
• Probe short circuit = 0.0v (recorder possibly) faulty. Replace
probe. If still 0.0v return/replace recorder.
• >2.0v = Replace recorder and probe.
• If probe voltage is off by more than a factor of 2 then
probe is faulty.

SECTION 100 – PRODUCT INTRODUCTION
Thermo Fisher Scientific Generic MBF700 Service Manual 15
Pen Not
Printing
Chart Loose
1. .Tighten chart knob
2. Attempt to turn chart counter-clockwise
3. If chart turns then tighten knob more
No Pen Pressure
1. Unscrew pen arm
2. Bend pen arm slightly downward
3. Reattach
4. Recalibrate (see “Not Calibrated”)
Pen Indicating
Wrong Temp
Not Calibrated
Recalibrate (see “Not Calibrated”)
Wrong Chart
Be sure proper chart is used with selected range
• 1 Flash -40 to +25C
• 2 Flashes -115to+50C
• 3 Flashes -200 to 0C
• 4 Flashes 0 to -+60C (newer units only)
Pen Will Not
Come
Completely
OffChart
Pen Arm Displaced
1. Unscrew pen arm
2. Align pen arm with pen arm bracket
3. Recalibrate (see “Not Calibrated”)

SECTION 100 – PRODUCT INTRODUCTION
16 Generic MBF700 Service Manual Thermo Fisher Scientific
Pen Arm
Oscillating
Not Calibrated
Recalibrate (see “Not Calibrated”)
No Recorded
Line
No Pen Pressure
1. Unscrew pen arm.
2. Bend pen arm slightly downward.
3. Reattach
4. Recalibrate (“Not Calibrated”).
Chart Loose
1. Tighten chart knob.
2. Attempt to turn chart counter-clockwise.
3. If chart turns, tighten knob more.