Thermo Electron 3920 Operating instructions

Model: 3920
Forma Environmental Chamber
Operating and Maintenance Manual
Manual No: 7043920 Rev. 3

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 makes no representations or war-
ranties with respect to this manual. In no event shall Thermo be
held liable for any damages, direct or incidental, arising out of or
related to the use of this manual.
MANUAL NUMBER 7043920
3 22678/IN-3229 1/17/05 Removed 270129 from terminals 15 and 16 temp. control aks
2 22454/IN-3208 9/14/04 Watlow SD 4-20mA standard; new schematics, configuration sheet ccs
-- 22452/IN-3208 9/14/04 Added noise reducing filters to Watlow 982 controllers, new schematics ccs
-- -- 6/30/04 Clarified unit clearance requirements ccs
1 22070/22129 1/29/04 Pre-programmed controller/changed thermal fuse aks
20843 10/28/03 Release 9 aks
REV ECR/ECN DATE DESCRIPTION By

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___________________________________________________________________________
iv
Warranty Notes
Information You Should Know Before Requesting Warranty Service
•Locate the model and serial numbers. A serial tag is located on the unit itself and on the operating manu-
al shipped with the unit.
• For equipment service or maintenance, or with technical or special application inquiries, contact Technical
Services at 1-888-213-1790 or 1-740-373-4763 (USA and Canada). Outside the USA, contact your local distrib-
utor.
Repairs NOT Covered Under Warranty
• Calibration of control parameters. Nominal calibrations are performed at the factory; typically ±1°C for
temperature, ±1% for gases, and ±5% for humidity. Our service personnel can provide precise calibrations as
a billable service at your location. Calibration after a warranty repair is covered under the warranty.
• Damage resulting from use of improper quality water, chemicals or cleaning agents detrimental to
equipment materials.
• Service calls for improper installation or operating instructions. Corrections to any of the following are
billable services:
1) electrical service connection
2) tubing connections
3) gas regulators
4) gas tanks
5) unit leveling
6) room ventilation
7) adverse ambient temperature fluctuations
8) any repair external to the unit
• Damage resulting from accident, alteration, misuse, abuse, fire, flood, acts of God, or improper
installation.
• Repairs to parts or systems resulting from unauthorized unit modifications.
• Any labor costs other than that specified during the parts and labor warranty period, which may
include additional warranty on CO2sensors, blower motors, water jackets, etc.

Environmental Chamber ___________________________________________________________________Table of Contents
v
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 Attaching the Drain Connections . . . . . . . . . . . . . . . .2 - 1
2.3 Remote Data Output . . . . . . . . . . . . . . . . . . . . . . . . . .2 - 1
a. 4-20 mA Output . . . . . . . . . . . . . . . . . . . . . . . . . . .2 - 1
b. Remote Alarm Contacts . . . . . . . . . . . . . . . . . . . . .2 - 1
2.4 Power Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 - 2
2.5 Start-Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2 - 2
2.6 Setting the Overtemp Safety Thermostat . . . . . . . . . .2 - 2
2.7 Setting the Undertemp Safety Thermostat . . . . . . . . .2 - 2
2.8 Preparing the (Optional) CoBex Recorder . . . . . . . .2 - 2
a. Installing the Battery . . . . . . . . . . . . . . . . . . . . . . .2 - 2
b. Changing the Chart Paper . . . . . . . . . . . . . . . . . . .2 - 3
c. Changing the Pen . . . . . . . . . . . . . . . . . . . . . . . . . .2 - 3
2.9 Honeywell Recorder (optional) . . . . . . . . . . . . . . . . .2 - 3
2.10 1900140 IR CO2Option . . . . . . . . . . . . . . . . . . . . . .2 - 3
a. Connecting the CO2Source (Figure 2-4) . . . . . . . .2 - 3
b. Setting the CO2Content . . . . . . . . . . . . . . . . . . . .2 - 4
c. CO2Control and Indicators . . . . . . . . . . . . . . . . . . .2 - 4
Section 3 - Start Up and Operation . . . . . . . . . . . . . . . . .3 -1
3.1 The Control Panel . . . . . . . . . . . . . . . . . . . . . . . . . . . .3 -1
3.2 Setting the Operating Temperature (Figure 3-4) . . . . .3 -2
3.3 Air Exchange Ventilator Caps . . . . . . . . . . . . . . . . . . .3 -2
3.4 Heatless Dryer P/N 1900139 (optional) . . . . . . . . . . . .3 -2
Section 4 - Routine Maintenance . . . . . . . . . . . . . . . . . .4 - 1
4.1 Cleaning the Incubator . . . . . . . . . . . . . . . . . . . . . . . .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 Temperature Sensor . . . . . . . . . . . . . . .5 - 1
5.4 Programming the Temperature Controller . . . . . . . . .5 - 1
a. Removing the Mechanical Lockout . . . . . . . . . . . .5 - 1
b. Removing the 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 CO2Controller Calibration . . . . . . . . . . . . . . . . . . . . .5 - 4
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
Supplement

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 3920
Side View
Model 3920

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 three (3)
inches clearance is required at the top and back of the incuba-
tor. This space is necessary to allow adequate air flow around
the refrigeration system. At least eight (8) inches of clearance is
required at the top of the incubator for service access.
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 oppo-
site 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 Attaching the Drain Connections
The cabinet’s 3/8” MPT drain line con-
nection 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, 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.
2.3 Remote Data Output
a. 4-20 Milliamp Output
The environmental chamber is equipped with 4-20mA out-
put for the remote transmission of temperature or CO2data. A
terminal strip is located on the back of the incubator for con-
venience. Refer to Figure 2-3 for terminal pin identification.
b. Remote Alarm Contacts
Remote alarm connections are also included on the termi-
nal 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 CO2go out of the set alarm limits.
2 - 1
Figure 2-3 Terminal Strip Connection
Figure 2-1
Figure 2-2

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. The power cord connector is the mains dis-
connect device for the incubator. Position the
incubator so the unit can be easily disconnected.
For Model 3920, plug the provided 10 ft. power cord with
the NEMA 14-20 plug into the grounded dedicated electrical cir-
cuit.
2.5 Start-Up
Preset the controls as follows:
Overtemp Safety Thermostat . . . . . . . . . . . . . Fully Clockwise
Undertemp Safety Thermostat . . . . . . Fully Counterclockwise
Main Power Switch . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .ON
Temperature Controller . . . . . . . . . . . . . . . . . .Desired Setpoint
Door Heater . . . . . . . . . . . . . . . . . . . . . . . . . .40% (factory set)
Turn the Main Power switch on. The Power indicator and
Heat indicator will light. Turn the Refrigeration switch on and
the indicator will light.
The compressor and refrigeration lights will not
come on if the chamber temperature is within
+4°C of the temperature controller.
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 counterclockwise
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 accom-
modate 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 degrees on the scale. The alarm should be silenced
and the undertemp indicator light should 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
will activate, power to the compressor will shut off, and the
chamber temperature will be maintained at the undertemp con-
trol 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 num-
bers 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.
2 - 2
Environmental Chamber ________________________________________________________________Installation and Set-Up

Environmental Chamber ________________________________________________________________Installation and Set-Up
2 - 3
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 9-volt battery, use only an alkaline style
battery. Dispose of the old battery following established envi-
ronmental practices.
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 2-4.
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 CO2
gas enters the incubator injec-
tion system. Two tanks may
be joined together with a man-
ifold 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. Insert the copper tubing provided with the unit 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 cop-
per tubing.
6. Check the tubing connection for leaks.
Figure 2-5
Figure 2-4

Environmental Chamber ________________________________________________________________Installation and Set-Up
2 - 4
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 temper-
ature and humidity to stabilize. Do not open door during the
stabilization 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
configuration record). When a CO2alarm occurs, the CO2
Alarm 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.
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.
Cool Indicator (Figure 3-4)
The Cool Indicator is illuminated when the refrigera-
tion system is activated.
Heat Indicator (Figure 3-4)
The Heat Indicator is illuminated when the heater is
activated.
A
B
C
E
Figure 3-2
D
Figure 3-3

Environmental Chamber_________________________________________________________________Start-Up and Operation
Changing the Setpoint
To raise or lower the setpoint, press the Up or Down
Arrow. Temperatures are set in .1°C increments.
3.3 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.
3.4 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.
Overtemp Safety Control, Indicator Light, and Audible
Alarm (Figure 3-3)
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 3-3)
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.
3.2 Setting the
Operating
Temperature (Figure
3-4)
The Watlow tem-
perature controller’s
upper numerical dis-
play shows the actual
temperature inside
the incubator chamber.
The lower display shows
the temperature setpoint.
F
I
J
G
H
3 -2
Figure 3-4

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.

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 
3.3 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, 5.7 * Verify and document all calibrations, 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 ceiling by removing 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 two screws
located on the left side of the control panel.
6. Pull the overtemp 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 Temperature Sensor
1. Locate the probe mounting plate in the center of the
right side of the incubator interior.
2. Open the mounting plate by removing the screws that
hold it in place.
3. Locate the humidity sensor mounted on the inside of the
panel in a black housing. Note the angle of the probe.
4. Grasp and unplug the probe from the probe cable.
5. When replacing the humidity sensor, be sure to mount
the probe at the same angle as it was originally mounted.
5.4 Programming the Temperature Controller
The Watlow temperature controller has been set at the fac-
tory to operate the incubator within the specifications listed in
Section 6 of this manual. Reference copies of the Watlow con-
figuration 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].
a. Removing the Mechanical Lockout
Make sure the unit is turned off.
Wearing a grounding wrist strap or maintaining constant
contact 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.
Environmental Chamber _____________________________________________________________________________Service
Figure 5-1