Thermo Scientific 3920 Operating instructions

Model 3920
Forma Environmental Chamber
Operating and Maintenance Manual 7053920 Rev. 0

Thermo Scientific
MANUAL NUMBER 7053920
0 25355/IN-3932 5/14/09 Original - line cord to 30A and FLA to 20A (including 4A for optional DLP) ccs
REV ECR/ECN DATE DESCRIPTION By
Preface
Environmental Chamber i

Thermo Scientificii Environmental Chamber
Preface
Important Read this instruction manual. Failure to read, understand and follow the instructions in this manual
may result in damage to the unit, injury to operating personnel, and poor equipment performance. s
Caution All internal adjustments and maintenance must be performed by qualified service personnel. s
Material in this manual is for information purposes only. The contents and the product it describes are subject to
change without notice. Thermo Scientific makes no representations or warranties 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.
©2009 Thermo Scientific. All rights reserved.

Thermo Scientific Environmental Chamber iii
Preface
Important operating and/or maintenance instructions. Read the accompanying text carefully.
Potential electrical hazards. Only qualified persons should perform procedures associated with this
symbol.
Equipment being maintained or serviced must be turned off and locked off to prevent possible injury.
Hot surface(s) present which may cause burns to unprotected skin, or to materials which may be
damaged by elevated temperatures.
Marking of electrical and electronic equipment, which applies to electrical and electronic equipment
falling under the Directive 2002/96/EC (WEEE) and the equipment that has been put on the market
after 13 August 2005.
This product is required to comply with the European Union’s Waste Electrical & Electronic
Equipment (WEEE) Directive 2002/96/EC. It is marked with the WEEE symbol. Thermo Scientific
has contracted with one or more recycling/disposal companies in each EU Member State European
Country, and this product should be disposed of or recycled through them. Further information on
Thermo’s compliance with this directive, the recyclers in your country and information on Thermo
products will be available at www.thermofisher.com.
4Always use the proper protective equipment (clothing, gloves, goggles, etc.)
4Always dissipate extreme cold or heat and wear protective clothing.
4Always follow good hygiene practices.
4Each individual is responsible for his or her own safety.

Thermo Scientificiv Environmental Chamber
Preface
Do You Need Information or Assistance on
Thermo Scientific Products?
If you do, please contact us 8:00 a.m. to 6:00 p.m. (Eastern Time) at:
1-740-373-4763 Direct
1-800-438-4851 Toll Free, U.S. and Canada
1-740-373-4189 FAX
http://www.thermo.com Internet Worldwide Web Home Page
Service E-Mail Address
Thermo Scientific
Controlled Environment Equipment
401 Millcreek Road, Box 649
Marietta, OH 45750
Our staff can provide information on pricing and give you quotations. We can
take your order and provide delivery information on major equipment items or make
arrangements to have your local sales representative contact you. Our products are listed on the
Internet and we can be contacted through our Internet home page.
Our staff can supply technical information about proper setup, operation or
troubleshooting of your equipment. We can fill your needs for spare or replacement parts or
provide you with on-site service. We can also provide you with a quotation on our Extended
Warranty for your Thermo Scientific products.
Whatever Thermo Scientific products you need or use, we will be happy to discuss your
applications. If you are experiencing technical problems, working together, we will help you
locate the problem and, chances are, correct it yourself...over the telephone without a service
call.
When more extensive service is necessary, we will assist you with direct factory trained
technicians or a qualified service organization for on-the-spot repair. If your service need is
covered by the warranty, we will arrange for the unit to be repaired at our expense and to your
satisfaction.
Regardless of your needs, our professional telephone technicians are available to assist you
Monday through Friday from 8:00 a.m. to 6:00 p.m. Eastern Time. Please contact us by
telephone or fax. If you wish to write, our mailing address is:
International customers, please contact your local Thermo Scientific distributor.
Sales Support
Service Support
[e-mail]

Thermo Scientific Environmental Chamber v
Preface
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.
• For equipment service or maintenance, or with technical or special application inquiries, contact Technical
Services at 1-800-438-4851 or 1-740-373-4763 (USA and Canada). Outside the USA, contact your local
distributor.
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 viThermo Scientific
Table of Contents
Installation and Set-Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-1
Location . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2
Preliminary Cleaning and Disinfecting . . . . . . . . . . . . . . . . . . . . . . . .1-2
Installing the Shelves . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2
Leveling the Unit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-2
Attaching the Drain Connections . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3
Remote Data Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3
Power Connection . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3
4-20 Milliamp Output . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3
Remote Alarm Contacts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-3
Start-Up . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-4
Set Overtemp Safety Thermostat . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-4
Set Undertemp Safety Thermostat . . . . . . . . . . . . . . . . . . . . . . . . . . .1-5
Prepare (Optional) CoBex Recorder . . . . . . . . . . . . . . . . . . . . . . . . . .1-5
Change Chart Paper . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6
Change Pen . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6
Honeywell Recorder (Optional) . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-6
IR CO2Option . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-7
Connect CO2Source . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-7
Set CO2Content . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-8
CO2Control and Indicators . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .1-8
Start-Up and Operation . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-1
Set the Operating Temperature . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-2
Air Exchange Ventilator Caps . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .2-3
Heatless Dryer P/N 1900139 (optional) . . . . . . . . . . . . . . . . . . . . . .2-3
Routine Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-1
Preventive Maintenance . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .3-2
Section 1
Section 2
Section 3

vii Environmental Chamber Thermo Scientific
Service . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1
Electrical Components . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-1
Replace Over/ Undertemp Probe & Thermostat . . . . . . . . . . . . . . . .4-1
Replace Temperature Sensor . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-2
Program Temperature Controller . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-2
Remove Mechanical Lockout . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-2
Remove Software Lockout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-3
Controller Configuration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-4
Offset Calibration (Temperature) . . . . . . . . . . . . . . . . . . . . . . . . . .4-4
Turn Hardware Lockout Back On . . . . . . . . . . . . . . . . . . . . . . . . . .4-6
Replace Optional Recorder and Probe(s) . . . . . . . . . . . . . . . . . . . . . .4-6
Calibrate the Recorder . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-7
Set the Door Heater Control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-8
CO2Controller Calibration . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .4-8
Specifications . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .5-1
Spare Parts . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .6-1
Refrigeration Schematic . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .7-1
Electrical Schematics . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .8-1
Warranty Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .9-1
Recorder Supplement
Table of Contents
Section 4
Section 5
Section 6
Section 8
Section 7
Section 9
Appendix A

Environmental Chamber 1-1Thermo Scientific
Section 1 Installation and Set-Up
Figure 1-1. Front View Figure 1-2. Side View

1-2 Environmental Chamber Thermo Scientific
Section 1
Installation and Set-Up
Locate the unit on a firm, level surface in an area of minimum ambient
temperature fluctuation. A minimum of three (3) inches clearance is
required at the top and back of the incubator. 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.
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.
Caution Before using any cleaning or decontamination method except
those recommended by the manufacturer, users should check with the
manufacturer 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. s
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.
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.
Location
Preliminary Cleaning
and Disinfecting
Installing the Shelves
Figure 1-3. Shelf Channels
Leveling the Unit

Environmental Chamber 1-3Thermo Scientific
Section 1
Installation and Set-Up
Remote Data Output
The cabinet’s 3/8” MPT drain line connection is located
on the rear (lower left side) of the cabinet. A P-trap
(Figure 1-4) 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.
The environmental chamber is equipped with 4-20mA output for the
remote transmission of temperature or CO2data. A terminal strip is
located on the back of the incubator for convenience. Refer to Figure 1-5
for terminal pin identification.
Remote alarm connections are also included on the terminal strip (Figure
1-5) 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 temperature or CO2go out of the set alarm limits.
See the serial tag on the side of the unit for electrical specifications, or refer
to the electrical schematics at the end of this manual.
Caution Connect the incubator to a grounded, dedicated circuit. The
power cord connector is the mains disconnect device for the incubator.
Position the incubator so the unit can be easily disconnected. s
Plug the provided 8 ft. power cord with a NEMA 5-20 plug into the
grounded dedicated electrical circuit. A NEMA 5-30 plug is provided on
units with the optional door light package.
Attaching the Drain
Connections
Figure 1-4. P-trap
Figure 1-5. Terminal Strip Connections
4-20 Milliamp Output
Remote Alarm Contacts
Power Connection

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.
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 thermostat is now set a few degrees above the control
temperature setpoint. When the chamber temperature rises to the
overtemp control point, the alarm system will activate, 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. s
Note The overtemp control is not directly calibrated. The numbers on the
dial are for reference only. s
1-4 Environmental Chamber Thermo Scientific
Start-Up
Section 1
Installation and Set-Up
Set Overtemp 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 temperature 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 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. s
Note The undertemp control is not directly calibrated. The numbers on
the dial are for reference only. s
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 1-6). 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 9-volt battery, use only an
alkaline style battery. Dispose of the old battery following established
environmental practices.
Environmental Chamber 1-5Thermo Scientific
Set Undertemp Safety
Thermostat
Section 1
Installation and Set-Up
Prepare (Optional)
CoBex Recorder
Figure 1-6. Recorder Components

1. Press the #3 Change Chart button (Figure 1-6) and hold it for 1
second until the pen begins to move to the left of the chart.
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.
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. s
The Honeywell, DR 4500 Recorder is a one to four-channel
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 4 and the
supplemental Honeywell Recorder manual.
1-6 Environmental Chamber Thermo Scientific
Change Chart Paper
Section 1
Installation and Set-Up
Change Pen
Honeywell Recorder
(Optional)

This section applies to units with the IR CO2option only.
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 manifold to ensure a
continuous CO2supply.
Install a two-stage pressure 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 monitor input pressure to the
incubator injection system. A suitable two-stage pressure regulator is
available.
The CO2source must be regulated at a pressure level of 15 psig, ±5.
Higher pressure levels may damage the CO2control system. The user
should determine the most economical pressure level, between 10 and 20
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 CO2 connection.
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.
Environmental Chamber 1-7Thermo Scientific
IR CO2Option
Section 1
Installation and Set-Up
Connect CO2Source
Figure 1-7. CO2 and Water Inlets

The Watlow SD CO2controller's upper display shows the actual CO2
content inside the chamber. The lower display shows the CO2setpoint.
Before setting the CO2Content, allow the chamber temperature 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.
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).
Caution To prevent CO2loss, the sample port must be capped when it is
not in use. s
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 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 4.
1-8 Environmental Chamber Thermo Scientific
Set CO2Content
Section 1
Installation and Set-Up
CO2Control and Indicators
Figure 1-8. CO2Control and Indicators

Environmental Chamber 2-1Thermo Scientific
Section 2 Start-Up and Operation
Main Power Switch and Indicator Light
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
The refrigeration switch controls power to the refrigeration system. The
refrigeration indicator lights when the refrigeration switch is on and the
compressor is receiving power.
Defrost Switch and Indicator Light
The defrost switch controls power to the defrost system. 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.
Caution The defrost switch must be set to Auto when the temperature
setpoint is 10°C, or below. s
Cool Indicator
The Cool Indicator is illuminated when the refrigeration system is acti-
vated.
Heat Indicator
The Heat Indicator is illuminated when the heater is activated.
Heat
Under temp
safety
Cool
Temperature control
Defrost
Off
Refrigeration
Over temp
safety
-65
-55
-25
-45
-35
RUN
MODE
SERIES 982
AUTO
DISPLAY
DEV
%OUT
L1 L2 L3 L4
PROCESS
WATLOW
12
3
Power
CO
alarm
2
sample port
SD
s
s
WATLOW
1
2
3
%
Auto
-15 -5-5 5
15
25
35
45
55
65
15
-15
5
25
35 45 55
65
75
85
95
105
Figure 2-1. Environmental Chamber Control Panel (shown with optional CoBex Recorder and optional CO2control

2-2 Environmental Chamber Thermo Scientific
Section 2
Start-Up and Operation
Overtemp Safety Control, Indicator Light, and Audible Alarm
The overtemp safety thermostat should be set slightly above the operat-
ing 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 numbers on the
dial are for reference only. s
If an overtemp condition occurs, the alarm can only be silenced by rais-
ing the overtemp safety thermostat setting. However, the cause of the
problem must be determined and corrected before normal operation
under the main temperature controller is resumed.
Undertemp Safety Control, Indicator Light and Audible Alarm
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 thermostat 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. s
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 corrected before normal operation
under the main temperature controller is resumed.
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 setpoint, press the Up or Down Arrow.
Temperatures are set in 0.1°C increments.
Set the Operating
Temperature

Environmental Chamber 2-3Thermo Scientific
Section 2
Start-Up and Operation
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 ventilator caps may be opened by
turning counterclockwise, and closed by turning clockwise.
Caution For optimum performance of the unit, the vent caps should be
closed at all times. s
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.
Heatless Dryer P/N
1900139 (optional)