Thermo Forma 3911 Operating instructions

Models: 3911, 3913, 3940 and 3949
Forma Environmental Chamber
Operating and Maintenance Manual
Manual No: 7043940 Rev. 2

Environmental Chamber ___________________________________________________________________________
i
Read This Instruction Manual.
Failure to read, understand and follow the instructions in
this manual may result in damage to the unit, injury to operat-
ing personnel, and poor equipment performance.
CAUTION! All internal adjustments and maintenance must
be performed by qualified service personnel.
Refer to the serial tag on the back of this manual.
The material in this manual is for information purposes only. The
contents and the product it describes are subject to change with-
out notice. Thermo Electron Corporation makes no representa-
tions or warranties with respect to this manual. In no event shall
Thermo be held liable for any damages, direct or incidental, aris-
ing out of or related to the use of this manual.
MANUAL NUMBER 7043940
2 22337 5/11/04 Removed reference to Hold/Run key for silence on Watlow, change pending ccs
1 22070/22129 1/29/04 Pre-programmed controller/changed thermal fuse aks
-- -- 1/26/04 Updated section 3.1.E dehumidification aks
-- 20843 11/20/03 Release 9 aks
REV ECR/ECN DATE DESCRIPTION By
Model Capacity
(cu. ft.)
Voltage
3911 11 208-220
3913 11 220-240
3940 29 208-220
3949 29 220-240

Environmental Chamber ______________________________________________________________________________Safety
ii
Important operating and/or maintenance instructions. Read the accompanying text carefully.
Ce symbole attire l'attention de l'utilisateur sur des instructions importantes de fonctionnement et/ou d'entretien. Il
peut être utilisé seul ou avec d'autres symboles de sécurité. Lire attentivement le texte d'accompagnement.
Wichtige Betriebs- und/oder Wartungshinweise. Lesen Sie den nachfolgenden Text sorgfältig.
Importante instruccions de operacion y/o mantenimiento. Lea el texto acompanante cuidadosamente.
Potential electrical hazards. Only qualified persons should perform procedures associated with this symbol.
Ce symbole attire l'attention de l'utilisateur sur des risques électriques potentiels. Seules des personnes qualifiées
doivent appliquer les instructions et les procédures associées à ce symbole.
Gefahr von Stromschlägen. Nur qualifizierte Personen sollten die Tätigkeiten ausführen, die mit diesem Symbol beze-
ichnet sind.
Potencial de riesgos electricos. Solo personas das capacitadadas deben ejecutar los procedimientos asociadas con este
simbulo.
Equipment being maintained or serviced must be turned off and locked off to prevent possible injury.
Risques potentiels liés à l'énergie. L'équipement en entretien ou en maintenance doit être éteint et mis sous clé pour
éviter des blessures possibles.
Geräte, an denen Wartungs- oder Servicearbeiten durchgeführt werden, müssen abgeschaltet und abgeschlossen wer-
den, um Verletzungen zu vermeiden.
El equipo recibiendo servicio o mantenimiento debe ser apagado y segurado para prevenir danos.
Hot surface(s) present which may cause burns to unprotected skin, or to materials which may be damaged by elevated
temperatures.
Présence de surface(s) chaude(s) pouvant causer des brûlures sur la peau non protégée, ou sur des matières pouvant
être endommagées par des températures élevées.
Heiße Oberfläche(n) können ungeschützter Haut Verbrennungen zufügen oder Schäden an Materialien verursachen,
die nicht hitzebeständig sind.
Superficias calientes que pueden causar quemaduras a piel sin proteccion o a materiales que pueden estar danados
por elevadas temperaturas.
√ Always use the proper protective equipment (clothing, gloves, goggles, etc.)
√ Always dissipate extreme cold or heat and wear protective clothing.
√ Always follow good hygiene practices.
√ Each individual is responsible for his or her own safety.

Environmental Chamber _________________________________________________________________________Service
iii

Environmental Chamber ___________________________________________________________________Table of Contents
iv
Table of Contents
Section 1 - Receiving . . . . . . . . . . . . . . . . . . . . . . . . . . . .1 - 1
1.1 Preliminary Inspection . . . . . . . . . . . . . . . . . . . . . . . .1 - 1
1.2 Visible Loss or Damage . . . . . . . . . . . . . . . . . . . . . . .1 - 1
1.3 Responsibility for Shipping Damage . . . . . . . . . . . . .1 - 1
Section 2 - Installation and Set-Up . . . . . . . . . . . . . . . . .2 - 1
2.1 Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 - 1
a. Choosing the Location . . . . . . . . . . . . . . . . . . . . . .2 - 1
b. Preliminary Cleaning and Disinfecting . . . . . . . . .2 - 1
c. Installing the Shelves . . . . . . . . . . . . . . . . . . . . . . .2 - 1
d. Leveling the Unit . . . . . . . . . . . . . . . . . . . . . . . . . .2 - 1
2.2 Water (Humidity System) and Drain Connections . . .2 - 1
a. Connecting Water Inlet for Humidity System . . . .2 - 1
b. Alternate Water Supply for Humidity System . . . .2 - 2
c. Connecting the Drain Line . . . . . . . . . . . . . . . . . . .2 - 2
2.3 Remote Data Output . . . . . . . . . . . . . . . . . . . . . . . . . .2 - 2
a. 4-20 Milliamp Output . . . . . . . . . . . . . . . . . . . . . .2 - 2
b. Remote Alarm Contacts . . . . . . . . . . . . . . . . . . . . .2 - 2
2.4 Power Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 - 2
2.5 Start-Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 - 3
2.6 Setting the Overtemp Safety Thermostat . . . . . . . . . .2 - 3
2.7 Setting the Undertemp Safety Thermostat . . . . . . . . .2 - 3
2.8 Preparing the (Optional) CoBex Recorder . . . . . . . .2 - 3
a. Installing the Battery . . . . . . . . . . . . . . . . . . . . . . .2 - 3
b. Changing the Chart Paper . . . . . . . . . . . . . . . . . . .2 - 4
c. Changing the Pen . . . . . . . . . . . . . . . . . . . . . . . . . .2 - 4
2.9 Honeywell Recorder (optional) . . . . . . . . . . . . . . . . .2 - 4
2.10 IR CO2 Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 - 4
a. Connecting the CO2 Source . . . . . . . . . . . . . . . . . .2 - 4
b. Setting the CO2 Content . . . . . . . . . . . . . . . . . . . .2 - 5
c. CO2 Control and Indicators . . . . . . . . . . . . . . . . . .2 - 5
Section 3 - Start Up and Operation . . . . . . . . . . . . . . . . .3 -1
3.1 The Control Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . .3 -1
3.2 Setting the Operating Temperature . . . . . . . . . . . . . . .3 -3
3.3 Setting the Operating Humidity . . . . . . . . . . . . . . . . . .3 -3
3.4 Air Exchange Ventilator Caps . . . . . . . . . . . . . . . . . . .3 -3
3.5 Heatless Dryer P/N 1900139 (optional) . . . . . . . . . . . .3 -3
Section 4 - Routine Maintenance . . . . . . . . . . . . . . . . . .4 - 1
4.1 Cleaning the Incubator . . . . . . . . . . . . . . . . . . . . . . . .4 - 1
a. Maintaining the Humidity Generator . . . . . . . . . . .4 - 1
Section 5 - Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5 - 1
5.1 Accessing the Electrical Components . . . . . . . . . . . . .5 - 1
5.2 Replacing Over/Undertemp Probe and Thermostat . .5 - 1
5.3 Replacing the Humidity/Temp Sensor . . . . . . . . . . . .5 - 1
5.4 Programming the Humidity/Temp Controllers . . . . . .5 - 1
a. Removing Mechanical Lockout . . . . . . . . . . . . . . .5 - 2
b. Removing Software Lockout . . . . . . . . . . . . . . . . .5 - 2
c. Controller Configuration . . . . . . . . . . . . . . . . . . . .5 - 2
d. Offset Calibration (Temp/Humidity) . . . . . . . . . . .5 - 2
5.5 Replacing the Optional Recorder and Probe(s) . . . . .5 - 3
a. Calibrating the Recorder . . . . . . . . . . . . . . . . . . . .5 - 4
5.6 Setting the Door Heater Control . . . . . . . . . . . . . . . . .5 - 4
5.7 Cleaning and Adjusting Humidity Steam Generator . .5 - 4
5.8 CO2 Controller Calibration . . . . . . . . . . . . . . . . . . . .5 - 5
Section 6 - Specifications . . . . . . . . . . . . . . . . . . . . . . . . .6 - 1
Section 7 - Spare Parts . . . . . . . . . . . . . . . . . . . . . . . . . . .7 - 1
Section 8 - Refrigeration Schematics . . . . . . . . . . . . . . .8 - 1
Section 9 - Electrical Schematics . . . . . . . . . . . . . . . . . .9 - 1
Warranty Information

Environmental Chamber ________________________________________________________________Installation and Set-Up
1 - 1
1.1 Preliminary Inspection
This incubator was thoroughly inspected and carefully
packed prior to shipment and all necessary precautions were
taken to ensure its safe arrival. Immediately upon receipt,
before the incubator is moved from the receiving area, carefully
examine the shipment for loss or damage. Unpack the incubator
and inspect its 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 evi-
dence 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 circum-
stances move the shipment from the receiving area.
1.3 Responsibility for Shipping Damage
For products shipped F.O.B. Marietta, Ohio, the responsi-
bility of Thermo Electron Corporation ends when the merchan-
dise is loaded onto the carrier’s vehicle.
On F.O.B. Destination shipments, Thermo and the carrier’s
responsibility ends when your Receiving Department personnel
sign a free and clear delivery receipt.
Whenever possible, Thermo will assist in settling claims
for loss or in-transit damage.
Section 1 - Receiving
Front View
Model 3940
Side View
Model 3940

Environmental Chamber ________________________________________________________________Installation and Set-Up
Section 2 - Installation and Set-Up
2.1 Location
a. Choosing the Location
Locate the unit on a firm, level surface in an area of mini-
mum ambient temperature fluctuation. A minimum of twelve
(12) inches of clearance is required at the top of the incubator
and a minimum of twelve (12) inches of clearance is required at
the rear of the incubator. This space is necessary to allow ade-
quate air flow around the refrigeration system.
b. Preliminary Cleaning and Disinfecting
Disinfect all interior surfaces with a general-use laboratory
disinfectant. Rinse thoroughly with sterile distilled water, then
70% ethanol. Dry with a sterile cloth as needed.
Disinfect the shelf channels and shelves, then rinse with
distilled water before installing.
Before using any cleaning or decontamination
method except those recommended by the manu-
facturer, users should check with the manufactur-
er that the proposed method will not damage the
equipment.
Accidental spills of hazardous materials on or
inside this unit are the responsibility of the user.
c. Installing the Shelves
The shelves may be installed at any level in the incubator.
Install a shelf channel on each side. With the tabs pointing up,
attach the channel by
locating the rivet into a
slotted hole, far end first.
Pull the channel toward
the front and slide the
front rivet on the channel
into the slotted hole and
press down. Make sure
that the channels are
opposite each other so that
the installed shelf will be
level.
d. Leveling the Unit
Place a bubble-type level on a shelf inside the incubator.
Adjust the feet as needed; counterclockwise to lengthen or
clockwise to shorten. Level the unit front-to-back and left-to-
right.
2.2 Water (Humidity System) and Drain Connections
a. Connecting Water Inlet for Humidity System
The humidity reservoir will require approximately three
cups (.710 liter) of water on the initial filling. For best opera-
tion of the incubator, sterilized distilled, demineralized or de-
ionized water should be used in the humidity reservoir. Water
purity should be in the resistance range of 50K Ohm/cm to 1M
Ohm/cm, or a conductivity range of 20.0 uS/cm to 1.0 uS/cm.
Refer to ASTM Standard D5391-93 or D4195-88 for measuring
water purity.
Distillation systems, as well as some types of reverse
osmosis water purity systems, can produce water in the quality
range specified. Tap water is not recommended as it may con-
tain chlorine, which can deteriorate the stainless steel. Tap
water may also have a high mineral content, which would pro-
duce a build-up of scale in the reservoir. High purity, ultra pure
or milli-q water is not recommended as it is an extremely
aggressive solvent and will deteriorate the stainless steel. High
purity water has a resistance of above 1M Ohm to 18M Ohm.
Even high purity water can contain bacteria and organic con-
taminants. Water should always be sterilized or treated with a
decontaminant, safe for use with stainless steel as well as safe
for the product, prior to being introduced into the humidity
reservoir.
Distilled or de-ionized water used in the humidity
reservoir must be within a water quality resist-
ance range of 50K Ohm/cm to 1M Ohm/cm to
protect and prolong the life of the stainless steel.
Use of water outside the specified range will
decrease the operating life of the unit and may
void warranty.
2 - 1
Figure 2-1

The water inlet is the 1/8” FPT connection located on the
rear top center of the incubator. A 1/4” hose fitting is provided
for a hose connection, if desired. Water inlet pressure must not
exceed 40 PSI. A manual shut-off valve should be installed
between the main water supply and the incubator.
To prevent mineral buildup on humidity generator
walls, it may be necessary to clean the humidity
generator with a non-metallic abrasive pad and
flush thoroughly every two to three months. Refer
to Section 5.7 Cleaning the Humidity Steam
Generator.
b. Alternate Water Supply for Humidity System
If an in-house water supply of the required purity range
(50K to 1M Ohm) is not available, an alternate water supply
method can be used. A large vented carboy (5 gal. minimum) of
water in the required purity range can be placed on top of the
unit. Connect it to the 1/8” FPT water inlet fitting, located on the
rear top center of the incubator.
NOTE: The maximum water consumption of this incubator
could be as high as 2 gallons per day. When using an alternate
water supply method, it is recommended that the supply be
checked periodically based on source volume.
c. Connecting the Drain Line
The cabinet’s 3/8” MPT drain line
connection is located on the rear (lower
left side) of the cabinet. A P-trap (Figure
2-2) is included with the unit and must be
installed on the connection.
To install the drain connection:
1. Using Teflon pipe thread tape,
tape the threads on the cabinet
drain connection.
2. Using an open end adjustable wrench, install the P-trap
onto the connection. Make sure the trap section is posi-
tioned down.
3. Push a piece of 3/8” ID tubing onto the trap and direct
the tubing to a convenient drain. Install a hose clamp on
the tubing, if desired. A condensate evaporator (P/N
1900031) or condensate pump (P/N 184062) may also be
used.
2.3 Remote Data Output
a. 4-20 Milliamp Output
The environmental chamber is equipped with 4-20 mA out-
put for the remote transmission of temperature and humidity
data. A terminal strip is located on the back of the incubator for
convenience. Refer to Figure 2-3 for terminal pin identification.
b. Remote Alarm Contacts
Remote alarm connections are also included on the terminal
strip (Figure 2-3) providing Normally Open (N.O.) and
Normally Closed (N.C.) contacts. C is the Common terminal.
The remote alarm will activate when either the incubator’s tem-
perature or humidity go out of the set alarm limits.
2.4 Power Connection
See the serial tag on the side of the unit for electrical speci-
fications, or refer to the electrical schematics at the end of this
manual.
Connect the incubator to a grounded, dedicated
circuit. For models 3911 and 3940, the power
cord connector is the mains disconnect device.
Models 3913 and 3949 have a fusable disconnect
located on the back of the unit. Position the incu-
bator so the unit can be easily disconnected.
For Models 3911 and 3940, plug the provided 10 ft. power
cord with the NEMA 14-20 plug into the grounded dedicated
electrical circuit.
Figure 2-2
Cabinet Drain P-trap
2 - 2
Figure 2-3
Environmental Chamber ________________________________________________________________Installation and Set-Up

Environmental Chamber ________________________________________________________________Installation and Set-Up
2 - 3
2.5 Start-Up
When the humidification system is operational, the incuba-
tor may be started. Preset the controls as follows:
Overtemp Safety Thermostat . . . . . . . . . . . . . Fully Clockwise
Undertemp Safety Thermostat . . . . . . Fully Counterclockwise
Main Power Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .ON
Humidity Controller . . . . . . . . . . . . . . . . . . . .Desired Setpoint
Temperature Controller . . . . . . . . . . . . . . . . . .Desired Setpoint
Door Heater . . . . . . . . . . . . . . . . . . . . . . . . . .40% (factory set)
For best overall performance of the incubator, the refrigera-
tion switch should be turned on for most applications. When
running Low or No humidity at high temperatures, the refriger-
ation switch may be turned off.
The defrost switch must be turned on when the
temperature setpoint is 10°C, or below.
2.6 Setting the Overtemp Safety Thermostat
Allow the chamber temperature and humidity to stabilize
then set the overtemp safety thermostat as follows:
1. Turn the overtemp control knob slowly counterclock-
wise until the audible alarm sounds and the overtemp
indicator lights.
2. Turn the overtemp control knob clockwise at least 2
degrees. The alarm should be silenced and the overtemp
indicator light should go out. The overtemp safety ther-
mostat is now set a few degrees above the control tem-
perature setpoint. When the chamber temperature rises
to the overtemp control point, the alarm system will acti-
vate, power to the heaters will shut off, and the chamber
temperature will be maintained at the overtemp control
point.
When an overtemp condition occurs, the cause must be
determined and corrected before normal operation under the
main temperature controller can be resumed.
Note: When the chamber temperature control setpoint is
changed, the overtemp safety thermostat must be reset to
accommodate the change.
Note: The overtemp control is not directly calibrated. The num-
bers on the dial are for reference only.
2.7 Setting the Undertemp Safety Thermostat
Allow the chamber temperature and humidity to stabilize,
then set the undertemp safety thermostat as follows:
1. Turn the undertemp control knob slowly clockwise until
the audible alarm sounds and the undertemp indicator
lights.
2. Turn the undertemp control knob counterclockwise at
least 2° on the scale. The alarm will silence and the
undertemp indicator light go out.
The undertemp safety thermostat is now set a few degrees
below the control temperature setpoint. When the chamber tem-
perature drops to the undertemp control point, the alarm system
activates, power to the compressor shuts off, and the chamber
temperature is maintained at the undertemp control point.
When an undertemp condition occurs, the cause must be
determined and corrected before normal operation under the
main temperature controller can be resumed.
Note: When the chamber temperature control setpoint is
changed, the undertemp safety thermostat must be reset to
accommodate the change.
Note: The undertemp control is not directly calibrated. The
numbers on the dial are for reference only.
2.8 Preparing the (Optional) CoBex Recorder
a. Installing the Battery
The seven-day circular chart recorder is located on the
front of the incubator cabinet and is protected by a glass door.
To prepare the recorder for operation, open the glass door
and snap the connector onto the 9-volt battery (Figure 2-4). If
the unit is operating, the green LED lights steady. If the unit is
not turned on, the LED blinks.
If the battery is weak or not connected, the green LED will
flash. If power is lost to the cabinet, the LED will also flash.
When replacing the 9V battery, use only an alkaline style bat-
tery. Dispose of the old battery following established environ-
mental practices.
Figure 2-4

Environmental Chamber ________________________________________________________________Installation and Set-Up
2 - 4
b. Changing the Chart Paper
1. Press the Change Chart button (#3) and hold it for 1 sec-
ond until the pen begins to move to the left of the chart.
See Figure 2-3.
2. Remove the existing chart by unscrewing the center
knob securing it.
3. Install the new chart, positioning it so that the correct
time line coincides with the time line groove on the
chart plate.
4. Replace the center knob and screw it tightly against the
chart.
c. Changing the Pen
1. Using a small flat blade screwdriver, loosen the 2 screws
holding the pen arm and remove the pen and arm as an
assembly.
2. Unsnap the plastic hinge securing the pen. Remove and
discard the old pen.
3. Install the new pen by snapping the hinge securely
around the pen arm.
4. Re-install the pen assembly by sliding the pen arm under
the screws, positioning the pen tip in the time line
groove. Tighten the screws.
5. Push the Chart Change button and hold it for 1 second
until the pen begins to move back onto the chart.
Note: Make sure that the pen is marking on the chart. It may
be necessary to gently lift the pen onto the chart paper.
2.9 Honeywell Recorder (optional)
The Honeywell, DR 4500 Recorder is a one to four-chan-
nel microprocessor-based, circular chart recorder.
The recorder is capable of recording both temperature and
humidity and printing alphanumeric chart data on blank heat-
sensitive chart. Refer to the Honeywell Configuration Record at
the end of Section 5 and the supplemental Honeywell Recorder
manual.
2.10 IR CO2Option
This section applies to units with the IR CO2option only.
a. Connecting the CO2Source (Figure 2-5)
For the most economical use, the liquid CO2supply tanks
should be without siphon
tubes, so that only CO2gas
enters the incubator injection
system. Two tanks may be
joined together with a mani-
fold to ensure a continuous
CO2supply.
Install a two-stage pres-
sure regulator, with indicating
gauges, 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 moni-
tor input pressure to the incubator injection system. A suitable
two-stage pressure regulator is available.
The CO2source must be regulated at a pressure level
between 5 and 10 psig. Higher pressure levels may damage the
CO2control system. The user should determine the most eco-
nomical pressure level, between 5 and 10 psig appropriate for
the desired CO2percentage in the chamber. Use only sufficient
pressure to maintain recovery time after door openings.
To connect the CO2supply:
1. Connect the CO2tubing to the 1/4” hose fitting installed
in the CO2inlet.
2. Check the tubing connection for leaks.
Figure 2-5

b. Setting the CO2Content
The Watlow SD CO2controller's upper display shows
the actual CO2content inside the chamber. The lower display
shows the CO2setpoint.
Before setting the CO2content, allow the chamber tempera-
ture and humidity to stabilize. Do not open door during the sta-
bilization period.
To set the CO2content, press the Up or Down Arrow
keys on the Watlow SD Controller.
c. CO2Control and Indicators
• Sample Port (Figure 2-6)
The sample port is used for checking CO2percentage in the
incubator chamber by an independent test instrument (such as
with a Fyrite, or similar CO2test instrument).
To prevent CO2loss, the sample port must be capped when it is
not in use.
•CO
2Alarm (Figure 2-6)
The CO2alarm is factory set to activate when the chamber
CO2content deviates from configured alarm set points (see con-
figuration record). When a CO2alarm occurs, the CO2Alarm
indicator on the control panel lights and the audible alarm
sounds.
The CO2alarm high and low setpoints are established
through the Watlow SD CO2controller (ALO, and AHI). Refer
to the Configuration Record included at the end of Section 5.
Environmental Chamber ________________________________________________________________Installation and Set-Up
2 - 5
Figure 2-6

Environmental Chamber_________________________________________________________________Start-Up and Operation
3 -1
Section 3 - Start Up and Operation
Figure 3-1, Environmental Chamber Control Panel
shown with optional CoBex Recorder and optional
CO2control
3.1 The Control Panel
Main Power Switch and Indicator Light (Figure 3-2)
The main power switch controls power to the incubator.
The main power indicator lights when the power switch is on
and the unit is receiving power.
Refrigeration Switch and Indicator Light (Figure 3-3)
The refrigeration switch controls power to the refriger-
ation system. The refrigeration indicator lights when the
refrigeration switch is on and the compressor is receiving
power.
Defrost Switch and Indicator Light (Figure 3-3)
The defrost switch controls power to the defrost sys-
tem. Setting the defrost switch to Auto will provide two
15-minute defrost cycles during a twenty-four hour period.
The defrost indicator lights when the defrost switch is on
and the incubator is in a defrost cycle.
The defrost switch must be set to Auto when the
temperature setpoint is 10°C, or below.
Humidity Switch and Indicator (Figure 3-3)
The humidity switch controls the power to the humidi-
fication system circuit. The humidity indicator light will
cycle as the controller toggles between humidify and dehu-
midify.
Dehumidify Switch and Indicator (Figure 3-3)
The dehumidify switch is used with the optional heat-
less dryer P/N 1900139 to provide dehumidification. The
heatless dryer injects dry air into the incubator chamber as
needed, to maintain humidity levels. When controlling
humidity, the dehumidification switch should be in the ON
position for most applications. The dehumidification light
will cycle on and off as the humidity controller toggles
between humidify and dehumidify.
A
B
C
E
Figure 3-2
D
Figure 3-3

Environmental Chamber_________________________________________________________________Start-Up and Operation
Audible Humidity Alarm and
Indicator Display (Figure 3-4)
The humidity alarm is a function
of the humidity controller (Figure 3-5).
When the cabinet humidity goes out-
side the set parameters of the con-
troller, L4 indicator on the controller
lights, the audible alarm sounds, and
the humidity alarm indicator (Figure 3-
4, Item I) on the control panel lights.
Humidity Alarm Setpoints
The humidity controller’s high and low limits are set by
the factory at 100% and 0%. Therefore, the system will go into
the alarm state when the humidity exceeds these percentages by
one percent. When operating the incubator near these high or
low humidity levels, frequent alarms may occur. This will
require that the controller’s high or low limit be reset to three or
four percent over the high limit or three or four percent under
the low limit. Refer to the Watlow User’s guide provided. Refer
also to the factory configuration records located at the end of
Section 5 of this manual.
Heat Indicator (Figure 3-4)
The Heat Indicator is illuminated when the heater is
activated.
Cool Indicator (Figure 3-4)
The Cool Indicator is illuminated when the refrigera-
tion system is activated.
Overtemp Safety Control, Indicator Light, and Audible
Alarm (Figure 3-4)
The overtemp safety thermostat should be set slightly
above the operating temperature of the incubator. In the event
of an overtemp condition, the overtemp safety thermostat will:
• Activate the audible alarm and the overtemp indicator
light.
• Interrupt power to the heaters and maintain the incubator’s
cabinet temperature at the overtemp safety control point.
Note: The overtemp control is not directly calibrated. The num-
bers on the dial are for reference only.
If an overtemp condition occurs, the alarm can only be
silenced by raising the overtemp safety thermostat setting.
However, the cause of the problem must be determined and cor-
rected before normal operation under the main temperature con-
troller is resumed.
Undertemp Safety Control, Indicator Light and Audible
Alarm (Figure 3-4)
The undertemp safety thermostat should be set slightly
lower than the operating temperature of the incubator. In the
event of an undertemp condition, the undertemp safety thermo-
stat will:
• Activate the audible alarm and the undertemp indicator
light.
• Interrupt power to the refrigeration system and maintain
the incubator’s cabinet temperature at the undertemp safety
control point.
Note: The undertemp control is not directly calibrated. The
numbers on the dial are for reference only.
If an undertemp condition occurs, the alarm can only be
silenced by lowering the undertemp safety thermostat setting.
However, the cause of the problem must be determined and cor-
rected before normal operation under the main temperature con-
troller is resumed.
F
I
J
G
H
3 -2
Figure 3-4
Figure 3-5

Environmental Chamber_________________________________________________________________Start-Up and Operation
3 -3
3.2 Setting the Operating Temperature (Figure 3-6)
The Watlow temperature
controller’s upper numerical
display shows the actual temperature
inside the incubator chamber. The
lower display shows the temperature
setpoint.
Changing the Setpoint
To raise or lower the set-
point, press the Up or Down Arrow.
Temperatures are set in 0.1°C incre-
ments.
3.3 Setting the Operating Humidity (Figure 3-7)
The Watlow humidity
controller’s upper numerical
display shows the actual humidity inside
the incubator. The lower display shows
the humidity setpoint.
To raise the setpoint, press the
Up or Down Arrows. Humidity is
set in one percent increments.
3.4 Air Exchange Ventilator Caps
Air exchange for the incubator is regulated through the
manually adjustable intake and exhaust ventilator caps located
on the top of the cabinet.
When viewed from the front of the incubator, the intake
cap is on the left and the exhaust cap is on the right. The venti-
lator caps may be opened by turning counterclockwise, and
closed by turning clockwise.
For optimum performance of the unit, the vent caps should
be closed at all times.
3.5 Heatless Dryer P/N 1900139 (optional)
The optional heatless dryer provides dehumidification for
the incubator chamber. The dehumidify switch must be turned
on for the dryer to operate. The dryer is controlled with the
humidity controller and should operate at 90 psi.
KL
M
Figure 3-6
NO
P
Figure 3-7

Environmental Chamber__________________________________________________________________Routine Maintenance
4 - 1
Section 4 - Routine Maintenance
4.1 Cleaning the Incubator
De-energize all potential sources of energy to this
unit and lockout/tagout their controls. (O.S.H.A.
Regulation, Section 1910-147.)
The continued cleanliness of the stainless steel used in this
unit has a direct effect on the appearance and operation of the
unit. Use the mildest cleaning procedure that will do the job
effectively. Clean the outside of the incubator with soap and
water or with any non-abrasive commercial spray cleaner.
Clean the inside of the chamber with alcohol and/or soap and
water. Disinfect the interior panels with a general use laboratory
disinfectant, diluted according to the manufacturer’s instruc-
tions. Rinse the surface thoroughly after each cleaning and wipe
the surfaces dry. Always rub in the direction of the finish pol-
ish lines.
Do not use chlorinated solvents on stainless steel
as they can cause rusting and pitting.
Do not use volatile or aromatic solvents for clean-
ing inside the cabinet as their residue can contam-
inate the cabinet environment.
The Thermopane glass door may be cleaned with commer-
cial glass cleaner or with a solution of ammonia and water.
a. Maintaining the Humidity Generator
Depending on the quality of water used in the humidifica-
tion system, it may be necessary to clean the humidity genera-
tor every 2 to 3 months. Refer to Section 5.7 for cleaning
instructions.

PREVENTIVE MAINTENANCE
Environmental Chambers
Your equipment has been thoroughly tested and calibrated before shipment. Regular preventive maintenance is important to keep your unit function-
ing properly. The operator should perform routine cleaning and maintenance on a regular basis. For maximum performance and efficiency, it is rec-
ommended that the unit be checked and calibrated periodically by a qualified service technician.
The following is a condensed list of preventive maintenance requirements. See the specified section of the instruction manual for further details.
Thermo Electron has qualified service technicians, using NIST traceable instruments, available in many areas. For more information on Preventive
Maintenance or Extended Warranties, please contact us at the number below.
Cleaning and calibration adjustment intervals are dependent upon use, environmental conditions and accuracy required.
Tips for all incubators:
• Do NOT use bleach or any disinfectant that has high chloros.
• Use sterile, distilled or demineralized water.
• Avoid spraying cleaner on the CO2sensor.
• Do not use powdered gloves for tissue cultures.

Preventive Maintenance for Environmental Chambers
Refer to Manual Section Action Daily Weekly Yearly
-- Inspect door latch, hinges and door gasket seal ;
3.4 Check air exchange ventilator caps for adjustment; open or close as required ;
4.1 Perform a complete decontamination procedure. Wipe down interior, shelves, Between Experiments
side panels with disinfectant. Rinse everything well with sterile distilled water. More frequent decontamination may be
required, depending on use and
environmental conditions.
5.4, 5.8 * Verify and document all calibrations, at the minimum. ;
5.7 * Inspect and clean the humidity generator, at the minimum. ;
-- Clean drip pan and drain lines ;
-- Clean refrigeration system condenser ;
-- Verify defrost cycle for below 10°C operation ;
-- Change filters(under normal conditions) ;
* Qualified service technicians only
** Regular monitoring routines of the various levels in your unit is encouraged.

5 - 1
Section 5 - Service
Servicing must be performed by qualified service
personnel only!
De-energize all potential sources of energy to this
unit and lockout/tagout their controls.
5.1 Accessing the Electrical Components
To gain access to the electrical components, remove the
two screws located on the left side of the control panel with a
Phillips screwdriver. The control panel is hinged and will swing
open.
5.2 Replacing Over/Undertemp Probe and Thermostat
1. Remove the incubator top right side air dam by remov-
ing the screws holding it in place.
2. Remove the top three screws from the top of the right
duct cover.
3. Lean the duct sheet out, and remove the Permagum seal
from around the probe access hole.
4. Remove the 15” copper capillary overtemp probe by
extracting two plastic clips that hold the probe in place.
5. Open the control panel by removing the four screws
located on the top and bottom of the control panel.
6. Pull the probe up through the access hole and into the
control panel.
7. Follow the wires from the probe to the thermostat
mounted on the control panel. Clip the plastic ties hold-
ing the overtemp cable to the existing wiring.
8. Pull the overtemp knob on the control panel off.
9. Remove the two screws that hold the overtemp assembly
to the control panel.
10. Disconnect the two wires from the back of the thermo-
stat assembly.
11. Pull the entire assembly from the panel, and remove the
unit.
12. Replace the thermostat and probe.
Note: Reseal probe access hole with Permagum and tie-wrap
overtemp cable to existing wires after replacing probe.
5.3 Replacing the Humidity/Temp Sensor
1. Follow instructions 1-6 from Section 5.2 to locate and
remove the probe from the chamber.
2. Clip any plastic ties securing the probe wiring.
Disconnect the probe.
3. Install the replacement probe in the chamber. When
replacing the humidity sensor, be sure to mount the
probe at the same angle as it was originally mounted.
4. Route the probe wire through the access hole into the
control housing.
5. Connect the probe to the appropriate controller wiring.
6. Reseal the probe access hole with Permagum and tie-
wrap the probe wire to existing wires.
5.4 Programming the Humidity/Temp Controllers
The Watlow temperature and humidity controllers have
been set at the factory to operate the incubator within the speci-
fications listed in Section 6 of this manual. Reference copies of
the Watlow configuration records are included at the end of this
section.
To prevent tampering, mechanical and software lockouts
are employed in the system. These lockouts must only be
removed by persons skilled in configuring controller software.
Re-programming either the temperature or humid-
ity controllers alters the factory defaults and will
seriously alter the performance of the incubator.
This may also void the warranty. Do not reconfig-
ure the controllers without first consulting the
Technical Services Department, [phone].
Environmental Chamber _____________________________________________________________________________Service

a. Removing Mechanical
Lockout
Make sure the unit is turned
off.
Wearing a grounding wrist
strap or maintaining constant con-
tact with the metal cabinet, press in
the four locking tabs on the frame
of the Temperature controller. There
are two tabs on either side as shown
in the front and side views in Figure
5-1. When all tabs are unlocked,
pull the controller module out of its
frame.
Looking at the top of the module, locate the red DIP switch
indicated in Figure 5-2.
With a fingernail or small
screwdriver, turn off SW #2
by moving the white toggle
down or towards the front
of the module. (SW#2 is the
top switch when looking at
the module from the right
side.)
Very carefully, replace
the module into its frame
and press firmly on the top
and bottom of the bezel
until all four locking tabs
“click” into place.
b. Removing Software Lockout
Press the Up and Down Arrows at the same time and hold
them for about three seconds. The words “inpt” (input) and
“set” will appear in the top and bottom displays. (Figure 5-3) If
numbers in the bottom display begin to scroll up or down, the
keys have not been pressed simultaneously. Try again.
Press the Up Arrow until “gLbL” (global) appears in the
upper display. The word “set” will remain in the lower display
(Figure 5-4).
5 - 2
Press the Mode key to scroll through the menus until the
lower displays show “Loc” (Figure 5-5). Press the Down arrow
key until the “2” becomes “0” (zero) as shown in Figure 5-6.
c. Controller Configuration
The Watlow 982 Temperature and Humidity Controllers
have been configured at the factory. Copies of the Watlow
Configuration records are included at the end of this section.
Do not reconfigure the controller without first
consulting the Technical Services department at
[phone].
d. Offset Calibration (Temp/Humidity)
It may be necessary to calibrate the temperature or humidi-
ty controllers to match an independent temperature or humidity
sensor. To do so, follow the next few steps.
1. Suspend an independent, calibrated sensor(s) in the cen-
ter of the interior chamber.
2. Allow approximately 30 minutes for the incubator to
stabilize.
3. Turn off the main power switch.
4. Wear a grounding wrist strap to avoid damaging any of
the electrical components.
5. Remove the 982 controller module(s) by pressing in the
four retaining tabs, two on the right side, two on the left
side. Refer to Figure 5-7. Pull the controller module out
by gently rocking it from side to side.
Environmental Chamber _____________________________________________________________________________Service
Figure 5-3 Figure 5-4
Figure 5-5 Figure 5-6
Figure 5-1
Figure 5-2
Figure 5-7

5 - 3
6. Looking at the top and
right side of the con-
troller module, locate
the red DIP switches
indicated (Figure 5-8).
Use your fingernail or a
small screwdriver, to
turn off SW 2 by mov-
ing the white toggle
towards the front of the
module as in the illustration.
7. Return the controller to its frame and firmly press the
top and bottom of the bezel until all four locking tabs
“click” into place.
8. Turn on the main power switch.
9. Press the Up and Down Arrow keys simultaneously for
3 seconds. The word “InPt” will appear in the upper dis-
play, and “set” will appear in the lower display.
10. Press the Down Arrow once, then continue to press the
Mode key until “LOC” appears in the lower display. The
upper display will show 2. Press the Down Arrow until 0
appears.
11. Press the Mode key once, then the Up Arrow once.
“InPt” will appear in the upper display, and “set” will be
in the lower display. Press the Mode key until “CAL 1”
appears in the lower display. Press the Up or Down
Arrow key to either add or subtract an offset value. This
value is the difference between the actual value shown
on the controller, and the reference sensor value.
12. Press the Display key once.
Environmental Chamber _____________________________________________________________________________Service
To turn hardware and software lockout back on:
1. Press the Up and Down Arrow keys simultaneously for
3 seconds. The word “InPt” will appear in the upper dis-
play, and “set” will appear in the lower display.
2. Press the Down Arrow once, then continue to press the
Mode key until “LOC” appears in the lower display. The
upper display will show 0. Press the Up Arrow until 2
appears.
3. Press the Display key once.
4. Turn off the main power switch.
5. Wear a grounding wrist strap to avoid damaging any of
the electrical components.
6. Remove the 982 controller module(s) by pressing in the
four retaining tabs, two on the right side, two on the left
side. Pull the controller module out by gently rocking it
from side to side.
7. Looking at the top and right side of the controller mod-
ule, locate the red DIP switches. Use your fingernail or
a small screwdriver, to turn on SW 2 by moving the
white toggle towards the back of the module.
8. Return the controller into its frame and press firmly on
the top and bottom of the bezel until all four locking
tabs “click” into place.
9. Turn on the main power switch.
5.5 Replacing the Optional Recorder and Probe(s)
1. Open the incubator door, and locate the probe mounting
plate attached to the center of the right interior wall.
Remove the mounting plate.
2. The recorder probe is attached to the lower end of the
back of the mounting plate. Remove the probe by care-
fully sliding it out of the housing.
3. Remove the screws securing the right side air dam.
4. Remove the top three screws on both edges of the right
duct sheet.
5. Lean the duct sheet out in order to remove the
Permagum seal from around the probe access hole.
6. Remove the four screws located on the top and bottom
of the control panel and open the control panel door.
Remove any Permagum from around the access hole.
7. Pull the probe(s) carefully up through the hole.
8. Follow the probe cable(s) to the back of the recorder,
and carefully clip any plastic ties holding the cable(s) to
other wiring.
9. Remove the four screws securing the recorder and pull it
carefully out from the front of the control panel.
10. Replace the recorder with the correct part.
Note: When replacing the recorder and probe(s), retie the probe
cable(s) to the existing wires.
Figure 5-8