Forma Scientific 3980 User manual

P.O. Box 649
Marietta, Ohio 45750
USA
Model 3980/3986
29 Cubic Foot
Reach-In Incubator
Manual 7003980
Important! Read this instruction manual prior to applying power to the unit.
Failure to comply with stated installation requirements may cause poor equipment
performance, component failure, or void warranty.
Complete model number and serial number are required when consulting the
factory for any reason.
Caution! All internal adjustments and maintenance must be performed by
qualified service personnel.
October 1988

TABLE OF CONTENTS
SECTION 1 - RECEIVING
1.1 Preliminary Inspection
1.2 Visible Loss or Damage
1.3 Concealed Loss or Damage
1.4 Responsibility for Shipping Damage
SECTION 2 - AUXILIARY EQUIPMENT
2.1 Shelves
2.2 Recorder
2.3 CH/P Portamatic CO2 Control System
2.4 Solid Faced Door
2.5 Digital Thermometer
2.6 Duplex Outlet
2.7 Thru-Wall Access Port
2.8 Fyrite CO2 Analyzer Kit
2.9 Two-Stage Pressure Regulator
2.10 Tissue Culture Shelves
SECTION 3 - SPECIFICATIONS
3.1 Construction
3.2 Dimensions
3.3 Capacity and Weight
3.4 Temperature
3.5 Humidity and CO2
3.6 Heating and Refrigeration
3.7 Electrical Requirements
3.8 Utility Connections
SECTION 4 - INSTALLATION
4.1 Location
4.2 Water and Drain Connections
4.3 Preparation of Humidification System
4.4 CO2 Connection

SECTION 5 - CONTROL & INDICATING DEVICES
5.1 Main Power Switch and Indicating Light
5.2 Refrigeration Switch and Indicating Light
5.3 Defrost Switch and Indicating Light
5.4 Digital Temperature Controller
5.5 Overtemp Safety Thermostat and Alarm
5.6 Humidity Controller
5.7 Humidity Range Selector
5.8 Humidity Switch and Indicating Light
5.9 Relative Humidity Indicator
5.10 Dehumidity Switch and Indicating Light
5.11 CO2 Flowmeter
5.12 Purge Level Dial
5.13 Purge Button
5.14 Purge Indicating Light
5.15 CO2 Sample Port
5.16 Air Pressure Gauge
5.17 Blower Switch
SECTION 6 - OPERATION
6.1 Power Connection
6.2 Initial Settings
6.3 Humidity System Operation
6.4 Setting the Overtemp Safety Thermostat
6.5 Overview of Humidification and CO2
6.6 CO2 System Operation
SECTION 7 - GENERAL MAINTENANCE
7.1 Cleaning
7.2 Cleaning Stainless Steel
7.3 General Instructions
SECTION 8 - SERVICING (For Qualified Personnel Only)
8.1 Checking and Recalibrating the Digital Temperature Controller
8.2 Recalibrating the Dial Thermometer
8.3 Recalibrating the Humidity Controller
8.4 Replacing the Overtemp Probe and Thermostat
8.5 Replacing the Humidity Sensor
8.6 Replacing the Rh Indicator
8.7 Replacing the Recorder and Probes
8.8 Removing the Top Section
PARTS LISTS, SCHEMATICS, SUPPLEMENTS, WARRANTY INFORMATION

SECTION 1 - RECEIVING
1.1 PRELIMINARY INSPECTION
This item was thoroughly inspected and carefully packed prior to shipment and all necessary
precautions were taken to ensure safe arrival of the merchandise at its destination. Immediately
upon receipt, before the unit is moved from the receiving area, carefully examine the shipment for
loss or damage. Unpack the shipment and inspect both interior and exterior for any in-transit
damage.
1.2 VISIBLE LOSS OR DAMAGE
If any loss or damage is discovered, note any discrepancies on the delivery receipt. Failure to
adequately describe such evidence of loss or damage may result in the carrier refusing to honor a
damage claim. Immediately call the delivering carrier and request that their representative perform
an inspection. Do not discard any of the packing material and under no circumstances move the
shipment from the receiving area.
1.3 CONCEALED LOSS OR DAMAGE
If damage is discovered upon unpacking the shipment, stop further unpacking, retain all packaging
material and immediately notify the delivering carrier, requesting that an inspection be performed
as soon as possible. Again, under no circumstances move the shipment from the receiving area.
1.4 RESPONSIBILITY FOR SHIPPING DAMAGE
For products shipped F.O.B. Marietta, Ohio, the responsibility of Forma Scientific, Inc. ends when
the merchandise is loaded onto the carrier's vehicle.
On F.O.B. Destination shipments, Forma Scientific's and the carrier's responsibility ends when
your Receiving Department personnel sign a free and clear delivery receipt.
Whenever possible, Forma Scientific, Inc. will assist in settling claims for loss or in-transit damage.

SECTION 2 - AUXILIARY EQUIPMENT
2.1 SHELVES
Additional shelves are available from stock. They are stainless steel, non-perforated, and have a
raised edge. The shelves slide easily into channel brackets and can be quickly removed for easy
cleaning.
Catalog No. 505071
2.2 RECORDER
Recorders maintain a permanent, accurate record of chamber humidity and/or temperature. All
recorders feature new long-life, disposable felt-tip inking pens.
TEMPERATURE RECORDER: Single Pen, 6" Chart, 7-Day Chart Drive, Factory Mounted.
Catalog No. 245131
TEMPERATURE RECORDER: Single Pen, 12" Chart, 7-Day Chart Drive, Factory Mounted.
Catalog No. 245196
TEMPERATURE AND HUMIDITY RECORDER: Dual Pen, 12" Chart, 7-Day Chart Drive,
Factory Mounted.
Catalog No. 245197
2.3 CH/P PORTAMATIC CO2 CONTROL SYSTEM
Model 3057 Portable Digital Automatic system for all reach-in incubators.
Catalog No. 3057
2.4 SOLID FACED DOOR
Polished stainless steel for light-tight applications.
Catalog No. 921005

2.5 DIGITAL THERMOMETER
This panel mounted thermometer provides direct digital temperature display in 0.1°C increments.
Catalog No. 260154
2.6 DUPLEX OUTLET
Weather-proof, mounted inside the incubator chamber.
115V - Catalog No. 505099
220V - Catalog No. 505094
2.7 THRU-WALL ACCESS PORT
1-3/4" diameter port with plug, centered on the right side of the chamber interior.
Catalog No. 505101
2.8 FYRITE CO2ANALYZER KIT
The Fyrite CO2analyzer kit instantly verifies the chamber CO2percentage in a 0 to 20% range. It
comes complete with a specially designed aspirator, sampling tube, and steel carrying case.
Catalog No. 220012
2.9 TWO-STAGE PRESSURE REGULATOR
A convenient two-stage general-purpose regulator for controlling cylinder gas pressure. The first
stage automatically reduces tank pressure to a pre-set intermediate level. The second stage reduces
pressure to the recommended (10 PSIG) incubator input level. It permits stable CO2flow and low
demand throughout the cylinder supply.
Catalog No. 965010
2.10 TISSUE CULTURE SHELVES
The 11" x 16" stainless steel shelves for culture dishes are designed for stacking to increase the
incubator storage area. Minimum order of 6 shelves.
Catalog No. 500171

SECTION 3 - SPECIFICATIONS
3.1 CONSTRUCTION
Exterior: Reinforced Steel
Interior: Polished Stainless Steel
Shelves: (6) Non-Perforated, Stainless Steel
Finish: Polyurethane Enamel
3.2 DIMENSIONS
Exterior: 88-1/2"H x 38"W x 31"D
225cmH x 97cmW x 87cmD
Interior: 60"H x 31"W x 27"D
153cmH x 79cmW x 69cmD
3.3 CAPACITY AND WEIGHT
Capacity: 29 Cubic Feet
823 Liters
Shelf Capacity: 19 Shelves with 103.3 Sq. Ft. available space
Shipping Weight: 850 lbs. (Nominal)
386 kg. (Nominal)
3.4 TEMPERATURE
Range: 0 to +60°C.
Control Uniformity: +/- 0.2°C.
3.5 HUMIDITY and CO2
Humidity Range: Above Ambient to 96%
CO2Range: 0 to 20%
3.6 HEATING AND REFRIGERATION
Heaters: (2) Wirewound
Refrigeration: 1/4 HP Air-Cooled Compressor

SECTION 3 – SPECIFICATIONS (continued)
3.7 ELECTRICAL REQUIREMENTS
Model 3980: 220V, 3 Wire, 17 FLA, 60 Hz
Model 3986: 220/240V, 2 Wire, 23 FLA, 50 Hz
3.8 UTILITY CONNECTIONS
3/8" NPT Drain Connection
1/8" NPT Water Connection
1/4" Compression Fitting for CO2

SECTION 4 - INSTALLATION
4.1 LOCATION
Locate the unit on a firm, level surface in an area of minimum ambient temperature fluctuation.
A minimum of 12 inches clearance at the top of the incubator is required. A minimum of 3 inches
clearance must exist between the back of the incubator and any walls or obstructions to ensure
adequate airflow around the refrigeration system.
4.2 WATER AND DRAIN CONNECTIONS
To ensure continuous satisfactory operation of the incubator, it is recommended that only distilled
water be used in the reservoir. In localities where the water has a high mineral content, the use of
distilled water is especially important.
CAUTION! Purity of the distilled water used in the incubator humidifier reservoir must be
within the 50K to 1M Ohm range to protect, and prolong the life of the stainless steel unit. Use
of tap water, or distilled water outside the specified range, will decrease the operating life of the
unit and may void the warranty.
The water inlet is the 1/8" NPT connection located at the top left side of the back of the incubator.
Water inlet pressure at the unit should be from 15 to 80 PSI. To facilitate service, it is
recommended that a manually operated shut-off valve be installed between the main water supply
and the incubator.
A 3/8" NPT drain connection is required on the Model 3980. A drain trap is necessary on the drain
line to maintain precise CO2control within the chamber.
NOTE: If the incubator is to be operated without humidity, but with CO2, the inner drain line must
be plugged to prevent erratic CO2control within the chamber.

SECTION 4 – INSTALLATION (continued)
4.3 PREPARATION OF THE HUMIDIFICATION SYSTEM
CAUTION! When the incubator is initially put into operation, the humidifier boiler is dry.
Before operating the incubator:
1) Turn the overtemp thermostat fully clockwise.
2) Set the humidity range switch to LOW.
3) Turn the humidity control knob to the lowest possible setting.
4) Turn the main power switch ON.
5) Turn the humidity switch ON.
6) Open the control panel. Water should be flowing to the water level tank mounted on the
side of the humidifier boiler. When a constant trickle of water begins to flow through the
clear plastic tubing, the humidifier boiler is operational.
4.4 CO2CONNECTION
To provide for the most economical use of CO2, a main supply of liquid CO2is recommended. The
liquid CO2should be supplied from tanks without siphon tubes to ensure that only CO2gas enters
the incubator injection system. It is also recommended that a two-stage pressure regulator, with
indicating gauges, be installed at the supply cylinder outlet. The high-pressure gauge should have
an indicating range of 0 to 2000 PSIG to monitor tank pressure. The low-pressure gauge should
have an indicating range of 0 to 30 PSIG to monitor actual input pressure to the incubator injection
system. Connecting two tanks will help to insure continuous availability of CO2. A suitable two-
stage pressure regulator is available from Forma Scientific, Inc.
The CO2pressure must be between 5 and 10 PSIG. Pressure higher than 10 PSI will damage the
CO2control system. The user should determine the most economical pressure level (between 5 and
10 PSIG) appropriate for the desired CO2percentage in the chamber.

SECTION 4 – INSTALLATION (continued)
To connect the CO2supply:
1) Slip the copper tubing provided with the unit, or a copper CO2supply tubing, as far as it
will go into the nut of the CO2connection.
2) Turn the nut until it is finger tight.
3) For reference, scribe the nut at the 6:00 position.
4) While holding the fitting body steady with a wrench, tighten the nut 1-1/4 turns until the
mark is at the 9:00 position.
5) Securely attach the CO2line to the open end of the copper tubing.
6) Check the tubing connection for leaks.

SECTION 5 - CONTROL & INDICATING DEVICES
5.1 MAIN POWER SWITCH AND INDICATING LIGHT
The main power switch controls the ON/OFF power to the incubator systems. The indicating light
is energized when the main power switch is ON, and the unit is receiving power.
5.2 REFRIGERATION SWITCH & INDICATING LIGHT
The refrigeration switch controls the power to the refrigeration unit compressor. The switch should
be in the ON position when the setpoint temperature is 4°C above ambient or below. It should also
be ON when the incubator is to be operated at high levels of humidity.
The refrigeration indicating light is energized when the refrigeration switch is on, and the
compressor is receiving power.
5.3 DEFROST SWITCH & INDICATOR LIGHT
The defrost switch controls power to the defrost system. The defrost timer is factory-set to provide
two 15-minute defrost cycles during a twenty-four hour period. The defrost switch should be
placed in the ON position when the temperature setpoint is 10°C or below.
CAUTION! Failure to turn the defrost switch "ON" when required will cause icing of the
refrigeration coil, which in turn will impair performance.
The defrost timer is energized by the main power switch, but timed defrosting can occur only when
the defrost switch is in the ON position.
The defrost indicator light is activated when the defrost switch is in the ON position and the
incubator is in a defrost cycle. The indicator light will go out when the defrost cycle is completed.

5.4 DIGITAL TEMPERATURE CONTROLLER
The solid state digital thumbwheel switch controls power to the incubator heater circuit. On a
demand for heat, the temperature controller energizes the heaters to bring the temperature up to
setpoint.
On the controller face, there are three manually adjustable rotary discs for direct dialing of the
chamber setpoint temperature. Temperature settings are made by rotating the individual discs until
the digits correspond with the desired temperature setpoint.
The disc on the extreme right is used for setting temperature in tenths of a degree Centigrade.
Settings for 0 to 0.9°C are selected on this disc. The two discs to the left are adjustable from 0 to
60°C.
The temperature controller indicating light cycles with the incubator heaters demand for heat.
5.5 OVERTEMPERATURE SAFETY THERMOSTAT AND ALARM
The overtemperature safety thermostat is designed to be set for a temperature slightly above the
operating setpoint temperature of the incubator. In the event of an overtemp condition in the
chamber the safety thermostat performs two functions:
1) It activates both the audible alarm and the overtemp indicating light.
2) It interrupts power to the heaters and maintains the temperature at the safety thermostat setpoint.
The overtemp control is not directly calibrated. The numbers (0 to 10) on the dial are for reference
only in setting the safety thermostat.
The source of any overtemp condition must be determined and corrected before the incubator can
be returned to the normal control system.
5.6 HUMIDITY CONTROLLER
The humidity controller is used to set the desired level of humidity in the incubator chamber.

5.7 HUMIDITY RANGE SELECTOR
The humidity range selector is used to select the proper humidity range:
Low Range: 10% to 50% RH
High Range: 40% to 100% RH
The range is set by pushing the switch to the LEFT for high range RH or to the RIGHT for low
range RH. The range selector must be set before the percent RH is selected.
5.8 HUMIDITY SWITCH & INDICATING LIGHT
The humidity switch controls the ON/OFF power to the humidity boiler circuit. The boiler heaters
will operate only if there is sufficient water in the boiler.
The humidity indicating light is activated when the humidity switch is in the ON position.
CAUTION! Be sure there is a sufficient supply of water in the boiler before activating the
humidification system!
5.9 RELATIVE HUMIDITY INDICATOR
The relative humidity indicator provides a direct read-out of chamber humidity in both ranges.
5.10 DEHUMIDITY SWITCH & INDICATING LIGHT
When the dehumidity switch is set to ON, the refrigeration compressor is locked in the cool
position providing a "drying action" from the refrigeration coil. This "drying action" of the
refrigeration cooling coil is limited and does not have the capability of taking the cabinet RH level
below ambient conditions. In order to obtain the most effective results from this drying action, the
humidity switch should be in the OFF position.
5.11 CO2FLOWMETER
The CO2flowmeter controls the flow of CO2into the incubator chamber.
A float ball indicates the CO2flow rate against the 0 to 100 arbitrary scale. A reading of 40 on the
scale provides approximately 5% CO2tension in the incubator.
CO2content should be checked with a Fyrite™ or similar device to insure the desired percentage.

5.12 PURGE LEVEL DIAL
The purge level dial is used to set the duration of the CO2purges. For example, when the dial is set
at 5%, the incubator will be purged with CO2for approximately 108 seconds. This is enough to
replace 5% of the air in the incubator with CO2.
The dial is marked for 5%, 10%, and 15%. Settings between these markings should be considered
arbitrary and will produce less than precise CO2percentages.
5.13 PURGE BUTTON
When pressed, the purge button permits a flow of CO2to the chamber to replace the CO2lost to the
air when the incubator door has been opened. The duration of the purge is dependent on the purge
level dial setting.
5.14 PURGE INDICATING LIGHT
The purge indicating light is energized when CO2is being purged into the incubator chamber. The
purge light will be energized for approximately 108 seconds when the purge dial is set at 5% purge.
5.15 CO2SAMPLE PORT
The sample port is used for checking CO2percentage by independent means, such as a Fyrite or
similar CO2measuring device. The sample port should be tightly capped when not in use to prevent
CO2loss to the atmosphere.
5.16 AIR PRESSURE GAUGE
The air pressure gauge indicates the air pump pressure in a range from 0 to 5 PSI.

5.17 BLOWER SWITCH
A two speed blower switch has been added to the unit to facilitate air flow in the incubator chamber
to reduce the possibility of culture desiccation.
The switch is located behind the control panel, either on the right side of the control panel housing
or on the right side of the component mount on the back of the hinged panel.
The switch has been factory-set to the high (up) position, but it may be turned to the low (down)
position if there is a problem with the cultures drying up.
WARNING: HIGH VOLTAGE IS PRESENT BEHIND THE CONTROL PANEL.
DISCONNECT THE UNIT FROM THE POWER SOURCE BEFORE OPENING THE PANEL
TO RESET THE SWITCH.

SECTION 6 - OPERATION
6.1 POWER CONNECTION
Connect the unit to an adequate power source:
Model 3980: 220 Volts, 3 Wire, 17 FLA, 60 Hz.
Model 3986: 220/240 Volts, 2 Wire, 16-23 FLA, 50 Hz.
6.2 INITIAL SETTINGS
Main Power Switch.................................................. OFF
Temperature Controller.........................Desired Setpoint
Overtemp Thermostat ....................10 (Fully Clockwise)
Refrigeration Switch ................................................ OFF
Defrost Switch ......................................................... OFF
Humidity Switch ...................................................... OFF
Humidity Range Selector.............................. Low Range
Humidity Controller.............................. Fully Clockwise
Dehumidity Switch .................... OFF (Fully Clockwise)
CO2Flowmeter .......................... OFF (Fully Clockwise)
CO2Purge Control ..................... OFF (Fully Clockwise)
Turn the main power switch ON. The main power indicating light and the heat light should be
energized. Turn the refrigeration switch ON. The refrigeration indicating light should be energized.
NOTE: Compressor may not switch ON if chamber temperature is less than 4° above or below
ambient temperature.
6.3 HUMIDITY SYSTEM OPERATION
CAUTION! Do not operate the humidity system without water in the boiler. To do so will cause
overheating of the boiler heaters, and the overtemp safety thermostat will shut down the system.
Following stabilization of the incubator temperature:
1) Set the humidity range selector to the desired range.
2) Set the humidity controller to the desired percent humidity.
3) Set the humidity switch to the ON position.

SECTION 6 – OPERATION (continued)
6.4 SETTING THE OVERTEMP SAFETY THERMOSTAT
Once the chamber temperature has stabilized, the overtemp thermostat should be set as follows:
1) Turn the overtemp control knob slowly counterclockwise until the audible alarm sounds and
the overtemp indicating light is energized.
2) Turn the control knob clockwise approximately two increments on the arbitrary scale. The
alarm should be silenced, and the overtemp indicating light should go out.
The overtemp thermostat is now set a few degrees above the control temperature setpoint. If
chamber temperature should rise above operation setpoint, the alarm system will be activated and
the temperature will be maintained at the overtemp setpoint.
Whenever the chamber temperature setpoint is changed, the overtemp thermostat must be reset to
accommodate the change.
6.5 OVERVIEW OF HUMIDIFICATION AND CO2
Of all the ways to measure incubator CO2levels, Forma's thermal conductivity method represents
the best combination of economy, accuracy and reliability possible today.
Thermal conductivity of the incubator atmosphere is affected not only by the quantity of CO2
present, but by the quantity of water vapor present in the incubator atmosphere as well. This effect
is linearly related to the absolute humidity of the atmosphere (See graph on following page).
In monitoring the effects of CO2, absolute humidity must be held constant so any change in thermal
conductivity is caused only by a change in the CO2concentration. Under the worst circumstances, a
change in absolute humidity could cause such a significant change in thermal conductivity that the
controller could shift the CO2content by as much as 4%.
Maintaining the water level inside the incubator is a relatively simple procedure. We cannot
emphasize strongly enough the importance of keeping the humidity in the incubator constant. Any
water pan, used in lieu of flooding the incubator floor, must be stainless steel and at least 187
square inches of surface area. Our tests indicate that smaller pans, bowls or non-metallic pans do
not provide adequate humidification, which can lead to incubator humidity variations with ambient
humidity shifts, resulting in CO2changes in the incubator.

When operating a dry incubator, as opposed to a humidified one, ambient humidity fluctuations
will affect CO2calibrations. Since the fluctuations possible in extreme ambient changes have less
effect on the total absolute humidity, the CO2calibration can be affected by as much as 1.5%.
When a change in humidity or temperature is needed, the CO2control can be easily zeroed for the
new condition.
One additional note: Temperature changes have little affect on CO2calibration, but do cause large
changes in the absolute humidity which is reflected in changes in CO2calibration.
6.6 CO2 SYSTEM OPERATION
1) Check the CO2percentage chart, and set the flow- meter to the desired level. The float ball
indicates the level of the setting.
2) Set the CO2purge control to the desired percentage.
3) Turn on the CO2at the source.
4) Press and release the CO2purge button. The purge light should indicate that CO2 is entering
the chamber and the CO2percentage is rising to the desired level.
NOTE: The CO2purge button should be pressed to regain CO2percentage after each incubator
door opening.

SECTION 7 - GENERAL MAINTENANCE
7.1 CLEANING
The chamber interior should be cleaned with alcohol and/or soap and water. The interior panels
should be sterilized with a general use laboratory disinfectant. Information about disinfectants
recommended by Forma Scientific, Inc. is included as a supplement to this manual.
The cabinet exterior may be cleaned with soap and water or a non-abrasive commercial spray
cleaner.
The Thermopane glass door may be cleaned with commercial glass cleaner or with a solution of
ammonia and water.
7.2 CLEANING STAINLESS STEEL
The continued cleanliness of the stainless steel utilized in Forma products has a direct effect on the
appearance and operation of the unit.
WARNING! Do not use chlorinated solvents on stainless steel, as they can cause rust.
NOTE: The use of volatiles or aromatic solvents is not recommended for cleaning cabinet
interiors, as residues could cause contamination of the chamber environment.
7.3 GENERAL INSTRUCTIONS
Use the mildest cleaning agents that will do the job effectively. To ensure maximum effectiveness
and to avoid marring the surface, always rub in the direction of the finish polish lines. Be sure to
rinse the surface thoroughly after every cleaning operation. To avoid watermarks, wipe the surface
dry.
Use the following pages as a guide for specific cleaning problems.