1

General Purpose and Chromatography 

Laboratory Refrigerator

with Alarms

316980H01 • Rev. B
2

Table of Contents

Introduction..........................................................................................................................................................3

Warning ........................................................................................................................................................3

Installation ..........................................................................................................................................................4

Unpacking ....................................................................................................................................................4

Visible Loss or Damage................................................................................................................................4

Concealed Loss or Damage ........................................................................................................................4

Packing List ..................................................................................................................................................5

Selecting a Location ....................................................................................................................................5

Leveling Unit ................................................................................................................................................5

Installing and Leveling Casters ....................................................................................................................6

Lamps ..........................................................................................................................................................6

Door Removal ..............................................................................................................................................6

Shelves ........................................................................................................................................................7

Electrical Connection ....................................................................................................................................8

Controls ..............................................................................................................................................................9

Panel Controls ..............................................................................................................................................9

Performance Characteristics ........................................................................................................................9

Displays and Features..................................................................................................................................9

Key Switch............................................................................................................................................10

Temperature Display ............................................................................................................................10

Unit’s LED’s ..........................................................................................................................................10

Mode LED ............................................................................................................................................10

Cool LED ..............................................................................................................................................10

Alarm LED’s ..........................................................................................................................................10

Keypads ..............................................................................................................................................11

Interior Light Switch..............................................................................................................................11

Operation ..........................................................................................................................................................12

Temperature Set point .........................................................................................................................12

Units ....................................................................................................................................................13

High Alarm Set Point............................................................................................................................13

Low Alarm Set Point ............................................................................................................................13

Alarm Silencing Menu ..........................................................................................................................13

Alarm Test Menu ..................................................................................................................................14

Control Mode ..............................................................................................................................................14

Loading ................................................................................................................................................14

Temperature Digression ......................................................................................................................15

Alarms ........................................................................................................................................................15

Over Temp Alarm..................................................................................................................................15

Under Temp Alarm................................................................................................................................15

Door Ajar Alarm (swinging door models only)......................................................................................16

Power Out Alarm ..................................................................................................................................16

Alarm Silencing ....................................................................................................................................16

Alarm Test ............................................................................................................................................16

Remote Alarm Contacts ......................................................................................................................17

Open Sensor ........................................................................................................................................18

Battery Back Up ..........................................................................................................................................18

Convenience Outlet ....................................................................................................................................18

Controller Service (Menus).........................................................................................................................19

Calibration Offset..................................................................................................................................19

Hold-Off Time ......................................................................................................................................19

Temperature Offset ................................................................................................................................20

Maintenance+ Cleaning......................................................................................................................................21

Cabinet .....................................................................................................................................................21

Condenser ............................................................................................................................................21

Condensate Evaporator Pan ......................................................................................................................21

Troubleshooting ................................................................................................................................................22

Replacement Parts............................................................................................................................................23

Wiring Diagrams................................................................................................................................................24
3

Introduction

Warning

Warnings alert you to a possibility of 

personal injury.

Caution

Cautions alert you to a possibility of 

damage to the equipment.

Note

Notes alert you to pertinent facts and 

conditions.

Hot surfaces alert you to a possibility

of personal injury if you come in

contact with a surface during use or

for a period of time after use.

Caution

Risk of electric shock.

Warning

These refrigerators are not approved 

for the storage of blood or blood

products!

Warning

This product is not intended, nor can it

be used, as a sterile or patient

connected device. In addition, this

apparatus is not designed for use in 

Class I,II or III locations as defined by 

the National Electrical Code, unless

otherwise noted.

Warning

As a routine laboratory precaution,

always wear safety glasses when 

working with this apparatus.

DANGER: RISK OF CHILD 

ENTRAPMENT. BEFORE YOU

THROW AWAY YOUR OLD

REFRIGERATOR OR FREEZER:

• TAKE OFF DOORS

• LEAVE THE SHELVES IN PLACE

SO THAT CHILDREN MAY NOT

 EASILY CLIMB INTO UNIT

 Warning

High voltage is supplied to PC board 

when key switch is OFF.

This manual is intended to provide installation and

operating instructions for your general purpose and 

chromatography refrigerators.

Your satisfaction and safety are important to us. A

complete understanding of this unit is necessary to attain

these objectives.

As the ultimate user of this apparatus, it is your

responsibility to understand its proper function and

operational characteristics. This instruction manual should

be thoroughly read and all operators given adequate

training before

Warning • This manual must be carefully read and

thoroughly understood before operating the

unit. Failure to follow directions or

precautionary measures could result in

serious adverse effects.

• This equipment must be used only as specified 

in these instructions. If used in a manner other

than as specified, the protection provided by the 

equipment may be impaired.

• This equipment is intended for indoor use only.

• This equipment must be earth grounded for safe 

operation.

• Disconnect unit line cord from power source

before performing any servicing or maintenance.

attempting to place this unit in service.

Awareness of the stated cautions and warnings, and

compliance with recommended operating parameters -

together with maintenance requirements - are important

for safe and satisfactory operation. The unit should be

used for its intended application; alterations or

modifications will void the Warranty.
4

Unpacking

Save all packing material if apparatus is received damaged. 

This merchandise was carefully packed and thoroughly

inspected before leaving our factory.

Responsibility for its safe delivery was assumed by 

the carrier upon acceptance of the shipment;

therefore, claims for loss or damage sustained in

transit must be made upon the carrier by the recipient

as follows:

Visible Loss or Damage

Note any external evidence of loss or damage on the

freight bill, or express receipt, and have it signed by the 

carrier’s agent. Failure to adequately describe such 

external evidence of loss or damage may result in the 

carrier’s refusing to honor your damage claim. The

carrier will supply the form required to file such a claim.

Concealed Loss or Damage 

Concealed loss or damage refers to loss or damage, 

which does not become apparent until the merchandise 

has been unpacked and inspected. Should either occur, 

make a written request to the carrier’s agent within 15 

days of the delivery date; then file a claim with the carrier 

since the damage is the carrier’s responsibility.

If you follow the above instructions carefully, we will 

guarantee our full support of your claim to be 

compensated for loss from concealed damage.

DO NOT – FOR ANY REASON – RETURN THIS UNIT 

WITHOUT FIRST OBTAINING AUTHORIZATION

Installation
INSTALLATION

5 

Packing List

The following items are located inside the refrigerator

chamber. If any of the following items are not present,

report the missing item to your local representative.

• Instruction Manual

• Warranty information

• Door Lock and Power Switch Keys

Selecting a Location

Choose a location for the refrigerator that will provide at

least three inches of clearance

Note

between the cabinet and 

any adjacent vertical surface at the sides and rear. 

Appropriate electrical power must be available. Locate

the refrigerator within 6 feet of the power outlet so that no 

extension cord is required.

The refrigerator must be level in order 

to provide adequate condensation 

drainage as well as proper door

alignment and operation. The

refrigerator should be in its final

operating location and set so that it is

firmly positioned

on the floor.

Leveling the Unit

The refrigerator must be level in order to provide adequate

condensation drainage as well as proper door alignment

and operation. The refrigerator should be in its final 

operating location and set so that it is firmly positioned on 

the floor. 

There are four leveling screws, one on each corner. Level 

the cabinet front to rear and side-to-side using the corner

leveling screws.

The front leveling screws are accessed by removing the

base grille, as described below:

1. Remove the lower grille attachment screws.

2. Grasp the grille with both hands.

3. Lift the grille approximately 1/2”.

4. Pull grille away from the refrigerator.

• Shelves and Casters
INSTALLATION

6

Caution

If the unit was tilted in excess of 30 

degrees, level it and do not apply 

electrical power for a minimum of

12 hours.

Installing and Leveling Casters 

Refrigerators come with four casters, which thread into

the base of the unit, one in each corner. Remove the 

leveling screws from the unit and use the wrench

provided to thread the casters completely into the 

base of the unit. 

See Figure 1.

Lamps

Caution

Improperly installed lamps may cause 

damage to the lighting circuit.

Prior to applying power to the unit, verify that all of the 

internal lamps are properly installed and fully engaged in 

the lamp holders. Proper lamp engagement is achieved 

by rotating the lamp 90° from its insertion position until it 

“snaps” or “clicks” into place.

Since the lamps in this unit are protected by shields, it is 

necessary to physically verify that the lamp has been 

rotated and locked into place.

Door Removal

(Sliding Door Models Only)

Each door has its own closing spring located at the top

of the door track. Each spring is set for proper tension. 

If doors do not close properly:

1. Check for cabinet level (see above).

2. Remove the door(s) by opening slightly then

lifting it. While maintaining upward pressure on

the door, pull the bottom outward until it clears 

the bottom track.

3. Check that spring in top track moves freely and 

that bottom track is free of debris. Check that 

rollers on bottom of door rotate freely.

Tighten 

using 

wrench 

provided

Refrigerator 

Base

Thread casters directly

into base at four 

corners

Figure 1
INSTALLATION

7 

Note

Chromatography units include

additional 1/2 shelves, which can

be used in place of the full shelves.

Shelves

Shipped inside each cabinet are shelves packed in plastic

and a bag of shelf supports.

Two different shelf supports are provided. The shorter tab 

length version is used on the front of the shelf. Shelf

spacing is adjustable to suit user requirements. Insert four

shelf supports for each shelf into the pilasters as shown. 

Place the shelf on the pilasters as shown in Fig’s 2 and 3.

Replacement shelves are available individually. Call 

Technical Service at 800­438­4851 for shelf part numbers.

Proper shelf orientation is illustrated in Figures 2 & 3.

Figure 2

Figure 3 - Place shelves at desired height on four

shelf supports.

Note

Note the numbers on the pilasters. 

Place supports on the same numbers 

on each pilaster to ensure the shelf will

be level.
INSTALLATION

8

Warning

Insufficient line voltage is often the 

cause of compressor start-up failure. 

It is strongly recommended that a 

dedicated circuit, conforming to the 

National Electrical Code, Article 440, 

be used for powering the

refrigerator.

Caution

Be sure that the power supply is the 

same voltage that is specified on the 

refrigerator's data plate.

Warning

For personal safety this unit must be 

properly grounded.

Warning

DO NOT under any circumstances cut 

or remove the third (ground) prong 

from the power cord. DO NOT use a 

two-prong adapter plug.

Warning

Do not use an extension cord. Use 

of an ungrounded cord or an 

overloaded circuit VOIDS the 

compressor warranty.

Electrical Connection

The frequency and nominal voltage requirements for the

unit are specified on the data plate, which is located on 

the interiors upper left side. Only plug the unit into a 

power source that meets these requirements. Low line 

voltage is often the cause of service complaints. 

With the unit running, check that the line voltage is 

within ±10% of that specified on the data plate.

The power cord on most units has a three prong

(grounding) plug (NEMA 5-15P). This plug mates with a 

standard three prong (grounding) wall receptacle (NEMA 

5-15R) to minimize the potential of an electrical shock

hazard. Where necessary models are equipped with a 

linecord and NEMA 5-20P plug. This plug requires a 

NEMA 5-20R receptacle.

The customer should have the wall receptacle and circuit 

checked by a qualified electrician to verify the receptacle 

is properly grounded and meets power requirements 

specified on the data plate.

Where a two prong wall receptacle is encountered, it is 

the personal responsibility and obligation of the user to 

have it replaced with a properly grounded three prong 

receptacle.

During compressor start-up, the unit will momentarily 

draw more current than under normal running conditions. 

To avoid nuisance tripping of circuit breakers, it may be 

necessary to install an HACR rated breaker.
9

Controls

Panel Controls

The control system provides both audible and visual 

indication of alarm conditions in an easy to read display

format. In addition, there are two sets of contacts

available for remote alarm switching.

 Temperature and alarm set points are directly entered in

°C or °F. 

Before operation, it is necessary to become familiar with

the refrigerator controls. All the refrigerator controls are 

located on the header panel. A layout of the controller 

and LED’s are given below.

 

 Performance Characteristics 

Temperature Range: 1.0° to 12.0°C (33.8° to 53.6°F) 

Temperature Stability: ±3°C

 Displays and Features On the right side of the header panel is the key switch.

 The key switch has three positions, OFF (O), Set-up (I) 

and Alarm Enable ( ). With the refrigerator plugged in 

and the key switch in the OFF position, the displays and 

Warning

High voltage is supplied to PC board 

when key switch is OFF. 
CONTROLS

10

refrigeration system are off. The control board remains 

energized in order to supply a charge to the battery. 

Key Switch

Turning the key switch to the middle position energizes

the circulation fans and the controller display. When the 

controller is in the Set-Up mode, the menu items can be 

set to the desired values. See Controller Set Up for a 

description of each. Once all menu items are set, the 

refrigerator should then be switched to the Alarm

Enabled position. While in the Alarm Enabled position, 

the menu items can be viewed but not changed. The key 

can be removed to secure the values entered.

Temperature Display

The temperature display indicates chamber temperature 

while in the control mode of operation and menu titles and 

values while entering menu items (see Menus). 

Units LED’S

The temperature display indicates chamber temperature

in both °C and °F. The current units are indicated by the 

corresponding LED located to the right of the temperature 

display.

Mode LED

The Mode LED is lit when the Menu keypad has been

pressed. It indicates to the user that the controller is in 

the menu selection mode.

Cool LED

The Cool LED is lit when the controller calls for cooling.

When this LED comes on the compressor should

energize.

Alarm LED’S

Door Ajar - This LED is illuminated when a refrigerator

door(s) is opened. This feature is not used in the sliding 

glass door models, since the circulating fans run 

continuously and the doors are spring loaded.

Over Temp – Indicates the current chamber temperature 

exceeds the high alarm temperature set point.

Under Temp – Indicates the current chamber temperature 

is lower than the low alarm temperature set point.

Power Out – Indicates AC power to the refrigerator is

disrupted.

Alarm Test – Indicates the controller is running an alarm 

test.

Note

The key can be removed in the

Off or the Alarm Enabled

position.

Caution

Alarms will only activate with the 

key in the Alarm Enabled 

position.
11

Keypads

Menu Keypad – Pressing the Menu keypad enters the

controller into the menu selection mode, designated by 

the illumination of the MODE LED. Repeatedly pressing 

the Menu keypad cycles through the list of menu items 

(see Menus). After the final menu, the controller returns 

to the control mode and the MODE LED turns off.

Up Arrow Keypad – Increases or changes menu values. 

Down Arrow Keypad - Decreases or changes menu

Values.

Interior Light Switch

The interior lamp(s) is controlled by a rocker switch located

on the control panel. This light may be operated any time

the cabinet power is turned on at the keyed power switch. 

If the interior lamp fails, replace with the same size and

wattage lamp. DO NOT USE REDUCED WATTAGE 

LAMPS. The reduced wattage lamps generally fail to light

below 60°F (15°C).

Be sure that lamps are properly installed by inserting 

ends into sockets and rotating lamp 90°. Failure to install 

lamps properly may cause damage to the lighting circuit. 

• Glass door models - The control panel light 

switch controls the interior light with the doors 

open or closed.

• Solid door models – The control panel light 

switch controls the interior light when the doors 

are open.

 

CONTROLS
12

Operation

Note

The “Pout” display is a normal 

occurrence when power is first 

applied to the controller. Press any

key to clear it.

The refrigerator is started by inserting the power switch 

key, which is found inside the unit, into the key switch. 

Turn the key to the middle (set up) position. The internal 

fans will start and the display will flash between Pout and 

the current chamber temperature. The “Pout” (power 

out) display indicates to the user that the controller has 

sensed a low voltage condition. This condition is normal 

during any start-up. See the Alarms section for details 

on the Pout message. Press any keypad to clear the 

Pout.

Controller Set-Up (Menus)

During normal operation, the refrigerator temperature is

displayed on the 4-character display. The compressor

cycles on and off to control the chamber temperature

between 1.0° and 12.0°C (33.8 to 53.6°F), selectable by

the user. The temperature set point, high and low alarm

set-points, units and display offset can be changed while

the key switch is in the set-up (middle) position. These

values can be viewed but not changed with the key

switch is in the alarm enabled position. The menu 

options are explained in the following sections.

There are 8 menus to select from, each can be

accessed by pressing the Menu keypad. Pressing the

Menu key- pad once brings up the first menu, which is

the temperature set point. The displays initially flash

SP followed by the last set temperature value. 

Pressing the Menu key- pad again, accepts the value

and displays the next menu, units select (CF). Each 

menu value is entered this way. The menus can be

changed only while the key switch is in the set up (I) 

position. They can be viewed but not changed while

the key switch is in the alarm enable( ) position. The

individual menus are described below.

Temperature Set point •

Temperature Set Point is factory pre­set at 4.0°C 

(39.2°F). Adjusting the temperature Set Point is 

not recommended.

•

Temperature Set Point (SP) – Adjustable from 

1.0 to 12.0°C or 33.8 to 53.6°F. Use the 

Up/Down Arrow keypads to change the

temperature and the Menu keypad to enter the

value and switch to the next menu.
OPERATION

13

Units • Units select (C,F) – Selects the desired

temperature display units in °C or °F. Use the Up 

Arrow keypad to change the units from C to F. Use

the Down Arrow keypad to switch from F to C. 

Press the Menu keypad to enter the units

value and continue. The appropriate units LED

will indicate the selected units.

High Alarm Set Point • High Alarm Set Point (AH) – Use the Up/Down

Arrow keypad to adjust the value that triggers a 

high alarm condition if the chamber temperature 

rises above it. The high alarm temperature 

range is from -33.0°C (-27.4°F) to 37.0°C 

(98.6°F).

• Factory pre­set at 16.0°C (60.8°F).

NOTE: The High and Low alarm set points can be 

adjusted to be within 3.5°C (6.3°F) of one another and no 

closer.

Low Alarm Set Point • Low Alarm Set Point (AL) – Use the Up/Down

Arrow keypad to adjust the value that triggers a 

low alarm condition. The low alarm condition 

occurs when the actual chamber temperature 

drops below the Low Alarm Set Point. The low 

alarm range is from -36.0°C (-32.8°F) to 34.0°C 

(93.2°F).

• Factory pre­set at -2.0°C (28.4°F).

Alarm Silencing Menu • Alarm Silencing (AS) – During an alarm condition,

while the key switch is in the Alarm Enable Mode,

this menu allows the user to silence the audible

alarm for 5 minutes. After the AS stops flashing,

the display will show n, press the Up Arrow keypad

to change the display to y. Press the Menu

Keypad and the audible alarm will turn off for 5 

minutes.
OPERATION

14

Alarm Test Menu • Alarm Test (At) –Use the Up Arrow keypad to

change the n to H. By subsequently pressing 

the Menu Keypad the controller will perform a 

High Alarm Test (see Alarm Test in Alarms

section). Use the Down Arrow Keypad to

change the display to L. Pressing the Menu

Keypad will activate the Low Alarm Test. 

Pressing the Menu Keypad while the display

shows n returns the unit to control mode (MODE

LED off).

NOTE: While in any of the above menu options, the 

controller will wait 15 seconds for a new value to be

entered. If there is no keypad activity within 15-seconds, 

the refrigerator will automatically shift to the Control Mode 

and the Mode LED will turn off.

Control Mode

The Control Mode of operation is indicated when the

Mode LED is OFF. With the desired temperature set 

point and alarm values entered, the refrigerator will then 

begin to control to the set temperature. There is a time 

delay between compressor activations. This delay begins 

the moment the controller is energized or the moment the 

compressor turns off during normal operation. The delay 

is added to provide time for the system pressure to drop 

before the compressor tries to start again.

Loading

Follow the guidelines below in order to provide optimal

refrigerator performance:

• When loading with critical samples, verify all 

alarms and features are operating properly.

• Space samples uniformly in the chamber.

• Keep samples away from the back wall that may 

obstruct airflow.

• It is best to load the refrigerator from bottom to 

top. Keeping the area next to the air intake and 

exhaust clear will help assure proper airflow. 
OPERATION

15

Temperature Digression

By pressing the Increase keypad while the refrigerator is

in the Control Mode, the display will show the warmest 

temperature recorded since the unit was energized or the 

digression values were reset. Pressing the Decrease 

keypad will display the coldest temperature recorded 

since the unit was energized or the digression values 

were reset.

To reset the temperature digression values, simply press 

the Increase and Decrease keypads at the same time. 

The display will show Clr, indicating the controller will 

begin recording new warm and cold digressions once 

more.

Alarms

Refrigerators are equipped with audible and visual alarms. 

They also feature remote alarm contacts. The key switch

must be in the Alarm Enable position for the audible alarm

and remote alarm contacts to activate. Alarm messages

are shown on both the temperature display and in the row

of Alarm LED’s located above the temperature display. The

following conditions will trigger an alarm:

• Chamber temperature is greater than the high 

alarm set point.

• Chamber temperature is less than the low alarm 

set point.

• Door has been left open for 3 minutes or more.

• AC power has been interrupted to the

refrigerator.

• Open sensor

NOTE: The Door Ajar Alarm is not available on the 

sliding glass door models.

Over Temp Alarm

If the refrigerator chamber temperature rises above the

High Alarm Set Point, the display will alternately flash the 

refrigerator chamber temperature and “HigH”. The Over 

Temp LED will be lit, the audible alarm will sound and the 

remote contacts will change state.

Under Temp Alarm

If the refrigerator chamber temperature falls below the

Low Alarm Set Point, the display will alternately flash the 

refrigerator chamber temperature and “Lo”. The Under 
OPERATION

16

Temp LED will be lit, the audible alarm will sound and the 

remote contacts will change state.

DoorAjar Alarm (swinging door models only) 

When a swinging door is opened, the Door Ajar LED 

lights and the display alternately flashes between the

refrigerator temperature and “door”. If a door is opened 

for 3 minutes, the audible alarm will sound and the 

remote alarm contacts change state.

Power Out Alarm

When AC power is lost, the display will alternately flash

between the current refrigerator temperature and “Pout”, 

the Power Out LED will light, the audible alarm will sound 

and the remote contacts will change state. When power 

is restored, the display will continue flashing the “Pout” 

message until it is cleared by the user by pressing any of 

the keypads.

Alarm Silencing

The audible alarm can be silenced by deactivating it at

the Alarm Silence Menu (see section earlier in this

manual). The audible alarm will silence for 5 minutes. It

will sound again at the end of the 5 minutes if the alarm

condition persists. Alarm silencing does not affect the

visual alarms.

Alarm Test

The Alarm Test feature is used to verify proper alarm

operation by simulating an increase or decrease in

chamber temperature. The alarm test function will work

for any value of high or low alarm set points. With the

key switch in the Set Up Position the remote and audible

alarms are not activated during an alarm test, as is the

case in an actual alarm condition.

The procedure for testing the alarms is simple. Press the 

Menu Keypad repeatedly until the display shows At (alarm 

test). Momentarily, the display will change to n. Press

the Up Arrow Keypad to change the display from n to H in 

order to perform a high alarm test. With the display 

showing H, press the Menu Keypad again and the

temperature display will begin to rise until it reaches the

High Alarm Set Point. Once the set point is reached, both 

audible and visual alarms should be activated (with the 

key switch in alarm enable position) and the remote alarm 

contacts should change state. To perform a low alarm

Note 

The key switch should be in the 

Alarm Enabled Position in order to 

test all alarm features
OPERATION

17

test, simply press the Down Arrow Keypad when the

display shows n. The display will then show L. Press

the Menu Keypad again in order to activate the low

alarm test.

Remote Alarm Contacts

In addition to the audible and visual alarms, there are two

sets of remote contacts on the side of the header panel,

which change state during an alarm. The upper set of

contacts provides both normally open and normally

closed switching.

Remote Alarm

Contacts

 Figure 4

All contacts are capable of switching up to 24 volts

AC/DC @ 2 amps. The common (C) and normally closed 

(NC) contacts open during an alarm. The common (C) 

and normally open (NO) contacts close during and alarm. 

The contacts for the Deluxe Remote Alarm are normally 

closed and open during and alarm. Figure 4 shows the 

location of the remote and deluxe alarm contacts.

Note 

Remote alarm contacts are active

only with the key switch in the Alarm

Enabled position.
OPERATION

18

Open Sensor

When the controller is unable to read from the sensor, the

display will show SnSr, indicating that a sensor error 

exists The display will alternately flash SnSr and HigH. 

The audible alarm will sound, the remote alarm contacts 

will change state and the over temp LED will illuminate.

Battery Back Up

The refrigerators are supplied with a rechargeable battery

backup. The battery will continue to supply power to the

controller and alarm features in the event of a power

outage. A fully charged battery can continue powering the

controller for up to 8 hours during a power failure.

The battery is recharged by the temperature controller 

during normal operation. The battery should be checked 

every six months and replaced when necessary (see 

Replacement Parts). Check the battery by unplugging the 

refrigerator and monitoring the controller operation. If the 

controller does not properly activate the alarm features for

2 hours, replace the battery. Under normal operation, 

the battery backup should last up to four years or 200 

charge/discharge cycles. 

Convenience Outlet

(Chromatography Refrigerators Only)

Chromatography Refrigerators are equipped with a 

convenience outlet located in the back wall. The power

to the outlets is protected by a circuit breaker. The

breaker is located just below and to the right of the

outlet. Pressing the breaker button resets the breaker

after a fault.

The total load to the convenience outlet should not

exceed 4 amps.

Caution

Moving location of control sensor 

voids warranty

Warning

The convenience outlet is LIVE at 

any time the unit is connected to an 

electrical power source, regardless

of the position of the key switch.
OPERATION

19

Controller Service (Menus)

The two final menu items, calibration offset and hold-off

time (oS and Ho), are not accessible from the main menu. 

In order to view and/or change them, the Menu keypad 

must be pressed and held for 5 seconds. The calibration 

offset (oS) menu will then be displayed briefly followed by 

the most recent offset value.

Calibration Offset

• Display Offset (oS) – Use the Up/Down Arrow 

keypads to adjust the offset value. Adjustable to

+/- 5.0°C (+/- 9.0°F). This value is added to the 

temperature display to correct for differences 

between actual and displayed chamber

temperature. See Calibration... for details. 

Press the Menu keypad to enter the new value

or to continue to the next menu.

Hold-Off Time • Hold-Off (Ho) – Use the Up/Down Arrow keypads to

adjust the Hold-Off time in minutes. Adjustable 

from 3 to 10. This value represents the delay time

between compressor activations. Increasing the

Hold-Off time can help prevent evaporator freezeup by increasing the defrost cycle time. Press the

Menu keypad to enter the new value and return to

temperature control mode.
OPERATION

20

Caution

INCREASING the offset value

DECREASES the temperature at

which the system controls. If the offset 

is inadvertently set too high, the chamber temperature can fall below zero

and lead to evaporator freeze-up.

Temperature Offset

In the event the refrigerator needs to be calibrated, a 

simple routine is available to adjust the display and control 

point to a referenced standard. To set a temperature offset while in the Control Mode (mode LED off), simply press

and hold the Menu key for 5 seconds. The display will

flash oS followed by the last temperature offset value. The

factory setting is 0.0. To change the offset value, press the

Increase or Decrease keypad to the value which when 

algebraically added to the last displayed temperature, will 

agree with the reference temperature. Next, press the

Menu key until the Mode LED turns off.

For Example:

The display indicates 4°C but a reference thermometer in 

the refrigerator chamber indicates 6°C. The operator 

presses and holds the Menu KEY until the display shows 

(oS) offset, then the value. Change the value from 0.0 to

2.0. The Menu key is then pressed repeatedly until the 

Mode LED turns off. Now the display indicates a 

chamber temperature of 6.0°C (approx.) and the

controller begins to cool to the desired temperature of

4.0°C. Allow an additional 30 to 40 minutes for the 

refrigerator to again stabilize. If the display is still 

inaccurate, repeat the calibration procedure.
Maintenance + Cleaning

21

Caution

When servicing the unit, disconnect 

plug from the electrical power source

Caution

Do not use any type of abrasive such 

as steel wool or fluids, such as gasoline, Naptha or paint thinner, that 

could be harmful to plastic materials, 

door gasket and/or painted surfaces 

for cleaning.

Cabinet

The cabinet interior should be cleaned frequently. Any

spilled liquid should be wiped off immediately. Stains 

resulting from some spills can be permanent if not quickly 

removed. The cabinet exterior should be cleaned

occasionally. A mild detergent and lukewarm water or a 

solution of bicarbonate of soda (1 tablespoon per gallon

of water) is recommended for cleaning the interior and

exterior of the cabinet. All surfaces should be rinsed and

thoroughly dried.]

Condenser

The condenser is located in front of the compressor fan,

which is behind the base grill. The condenser should be

cleaned before becoming clogged with dirt/dust. 

Construction or other dirt causing environments may

significantly increase the required frequency. The

condenser should be cleaned at least once a year.

Condensate Evaporator Pan 

The condensate evaporator pan is located behind the 

compressor fan, which is behind the base grill. This pan 

should be cleaned at least once a year to prevent foul 

odors and operate efficiently. Vacuum clean if dry, or 

sponge clean with soapy water.
22

Troubleshooting

This table is intended to assist in resolving user-correctable Refrigerator problems by relating symptoms to

their likely causes. If service beyond the scope of this table is required, contact Service Division at 1-800-

438-4851.

Symptom Probable Cause Action

Does Not Run Unit Unplugged Plug in Unit

Blown fuse or tripped circuit breaker Check fuse or circuit breaker at 

breaker box

Runs Continuously Frost buildup on refrigeration Turn unit off and allow it to defrost. 

coils.

Refrigerator over-loaded. Remove contents from top shelf of 

unit.

Clicking Sound The compressor is equipped with Disconnect power and allow unit to 

a thermal protector. This device sit for about an hour, then retry. If 

shuts off the compressor when it condition persists, call for service. 

becomes too hot. A clicking sound

occurring about every 30 seconds 

indicates this protector is working

Insufficient Cooling Set temp is too high Reduce temperature setting, verify

Cool LED turns on in 3 minutes.

Condenser coil dirty Clean condenser coil with a vacuum 

cleaner

Unit frosted Defrost unit

Offset (oS) value is too low. Increase offset value.
Replacement Parts

23

Replacements for Laboratory Refrigerator parts serviceable by the user may be ordered, by part number, from

Service at 1­800-438-4851.

Solid State Relay (K2) 25A 88616

Magnetic Relay (K1) SPST 102259

Magnetic Relay (K1) DPDT 102260

Alarm Version Temperature Controller 316637H01

Chart Recorder Manual 316983H01

Rechargeable Battery 104711

Temperature Sensor 104163

Solid State Relay(K2) 45A 316764H01

Shelf Support (Front) 103264

Shelf Support (Rear) 103265
24

Wiring Diagrams

 

Hinged Glass Door Models

POWER CORD

115 VAC

COM

K1

NO

CHART RECORDER

OPTIONAL

COMPRESSOR

LIGHT SWITCH LAMP BALLAST

2 1

K2

CONDENSER 

FAN

7

6

5

3

2

1

C

A

1

2

3

OUTPUT TO 

REMOTE 

ALARM

TB2

BATTERY (+)

(-)

B1

2

1

OUTPUT 

TO DELUXE 

ALARM 

SYSTEM

TB1

SYSTEM 

RELAY

12 VDC

0

1

K1

WHITE

BLACK

GREEN

12 VDC RED

BROWN

SW1

CONTROL ON/OFF CIRCUIT

PURPLE/WHITE

ALARM ENABLE

BLUE/WWITE

YELLOW/WHITE

PURPLE

J4

J3

KEY SWITCH

RED

BROWN

GRAY

GRAY

Y

YELLOW/WHITE

G/Y

B W

PURPLE/WHITE

COM

5 2 6 3 4 1

TEMPERATURE

CONTROLLER

2

5

4

1

6

3

NC

NO

DOOR

AJAR

LINE EARTH NEUT

12 VDC

4 3

COMPRESSOR 

RELAY

K2 (-) (+)

BLACK WHITE

EVAPORATOR FANS

(QTY MAY VARY)

DOOR SWITCH

(QTY MAY VARY)

CHROMATOGRAPHY UNITS ONLY (QTY MAY VARY)

CIRCUIT BREAKER
25

Wiring Diagrams

Hinged Solid Door Models

POWER CORD

115 VAC

COM

K1

NO

CHART RECORDER

OPTIONAL

COMPRESSOR

LIGHT SWITCH LAMP BALLAST

2 1

K2

CONDENSER 

FAN

2

1

OUTPUT TO 

DELUXE 

ALARM 

SYSTEM

TB1

BATTERY (+)

(-)

B1

1

2

3

OUTPUT 

TO 

REMOTE 

ALARM

TB2

7

6

5

3

2

1

C

A

SYSTEM 

RELAY

12 VDC

0

1

K1

BLACK WHITE

DOOR SWITCHS

(QTY MAY VARY)

EVAPORATOR FANS

(QTY MAY VARY)

(-) (+)

K2

COMPRESSOR 

RELAY

4 3

12 VDC

LINE EARTH NEUT

DOOR

AJAR

NO

NC

3

6

1

4

5

2

TEMPERATURE

CONTROLLER

5 2 6 3 4 1

COM

PURPLE/WHITE

B W

G/Y

YELLOW/WHITE

Y

GRAY

GRAY

BROWN

RED

KEY SWITCH

J3

J4

PURPLE

YELLOW/WHITE

BLUE/WWITE

ALARM ENABLE

PURPLE/WHITE

CONTROL ON/OFF CIRCUIT

SW1

BROWN

12 VDC RED

GREEN

BLACK

WHITE
Wiring Diagrams

Sliding Glass Door Models

POWER CORD

115 VAC

COM

K1

NO

CHART RECORDER

OPTIONAL

COMPRESSOR

LIGHT SWITCH LAMP BALLAST

2 1

K2

CONDENSER 

FAN

2

1 OUTPUT TO 

DELUXE 

ALARM 

SYSTEM

TB1

1

2

3

OUTPUT TO 

REMOTE 

ALARM

TB2

BATTERY (+)

(-)

B1

7

6

5

3

2

1

C

A

SYSTEM 

RELAY

12 VDC

0

1

K1 (-) (+)

K2

COMPRESSOR 

RELAY

4 3

12 VDC

LINE EARTH NEUT

NO

NC

3

6

1

4

5

2

TEMPERATURE

CONTROLLER

5 2 6 3 4 1

COM

PURPLE/WHITE

B W

G/Y

YELLOW/WHITE

Y

GRAY

GRAY

BROWN

RED

KEY SWITCH

J3

J4

PURPLE

YELLOW/WHITE

BLUE/WWITE

ALARM ENABLE

PURPLE/WHITE

CONTROL ON/OFF CIRCUIT

SW1

BROWN

12 VDC RED

GREEN

BLACK

WHITE

BLACK WHITE

EVAPORATOR FANS

(QTY MAY VARY)

CIRCUIT 

BREAKER

CHROMATOGRAPHY UNITS ONLY