KitchenAid KSBP25FKSS00 User manual

TECHNICAL EDUCATION
JOB AID 4317290A
KAR-12
2001 K MODEL
COUNTER DEPTH
SIDE-BY-SIDE REFRIGERATOR
WITH VARIABLE
CAPACITY COMPRESSOR
MODELS:
KSBP25FKSS00
KSBS25FKBL00
KSBS25FKBT00
KSBS25FKWH00
KSCS25FKSS00
KSFS25FKBL00
KSFS25FKBT00
KSFS25FKWH00

- ii -
WHIRLPOOL CORPORATION assumes no res onsibility for any re airs made
on our roducts by anyone other than Authorized Service Technicians.
FORWARD
This Job Aid, “KitchenAid 2001 K Model Counter De th Side-By-Side Refrigerator With Variable
Ca acity Com ressor” (Part No. 4317290A), rovides the technician with information on the
installation and service of the Side-By-Side Refrigerator. It is to be used as a training Job Aid and
Service Manual. For s ecific information on the model being serviced, refer to the “Use and Care
Guide,” or “Tech Sheet” rovided with the refrigerator.
The Wiring Diagrams and Stri Circuits used in this Job Aid are ty ical and should be used for
training ur oses only. Always use the Wiring Diagram su lied with the roduct when servicing
the unit.
GOALS AND OBJECTIVES
The goal of this Job Aid is to rovide detailed information that will enable the service technician to
ro erly diagnose malfunctions and re air the Side-By-Side Refrigerator.
The objectives of this Job Aid are to:
• Understand and follow ro er safety recautions.
• Successfully troubleshoot and diagnose malfunctions.
• Successfully erform necessary re airs.
• Successfully return the Side-By-Side Refrigerator to its ro er o erational status.
Co yright © 2002, Whirl ool Cor oration, Benton Harbor, MI 49022

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TABLE OF CONTENTS
Pag
GENERAL............................................................................................................................... 1-1
Safety First......................................................................................................................... 1-1
Electrical Power Su ly & Grounding Requirements ................................................... 1-1
Electrostatic Discharge (ESD) Sensitive Electronics.................................................... 1-2
Model & Serial Number Designations ................................................................................ 1-3
Model & Serial Number Label And Tech Sheet Locations................................................. 1-4
S ecifications..................................................................................................................... 1-5
Refrigerator Warranty ........................................................................................................ 1-7
INSTALLATION INFORMATION ........................................................................................... 2-1
THEORY OF OPERATION ..................................................................................................... 3-1
COMPONENT ACCESS ......................................................................................................... 4-1
Com onent Locations ........................................................................................................ 4-1
Removing The Touch/Dis lay Board, The Insert And Overlay,
& The Motorized Air Door ............................................................................................... 4-2
Removing A Thermistor ..................................................................................................... 4-4
Removing A Door Switch ................................................................................................... 4-5
Removing A Light Socket .................................................................................................. 4-6
Removing The Water Reservoir ........................................................................................ 4-7
Removing The Ice Maker And The Auger Motor & Crush/Cube Solenoid......................... 4-9
Removing The Eva orator Fan Motor, The Bimetal,
The Defrost Heater, & The Eva orator ......................................................................... 4-11
Removing The Condenser Fan Motor ............................................................................. 4-15
Removing The Com ressor ............................................................................................. 4-16
Removing The Inverter Assembly.................................................................................... 4-17
Removing The Main Control Board Assembly ................................................................. 4-18
Removing The Water Dis enser Fill Tube ....................................................................... 4-20
Removing The Water Valve ............................................................................................. 4-22
Removing The Freezer Door Handles & Freezer Door ................................................... 4-23
Removing A Roller ........................................................................................................... 4-25
COMPONENT TESTING ........................................................................................................ 5-1
Thermistor.......................................................................................................................... 5-1
Eva orator Fan Motor ........................................................................................................ 5-2
Condenser Fan Motor ........................................................................................................ 5-2
Com ressor & Inverter....................................................................................................... 5-3
Motorized Air Door ............................................................................................................. 5-4
Defrost Heater & Bimetal ................................................................................................... 5-4
Main Control Board ............................................................................................................ 5-5
Crush/Cube Solenoid......................................................................................................... 5-6
Ice Maker Auger Motor ...................................................................................................... 5-6
Water Valve Solenoid ........................................................................................................ 5-7
Door Switch ....................................................................................................................... 5-7

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DIAGNOSIS & TROUBLESHOOTING ................................................................................... 6-1
Diagnosis ........................................................................................................................... 6-1
Pre-Diagnostics Checks ................................................................................................. 6-1
Diagnostics Mode ........................................................................................................... 6-1
Water Filter In ut (WFI) Test .......................................................................................... 6-2
Troubleshooting Chart ....................................................................................................... 6-3
WIRING DIAGRAMS & STRIP CIRCUITS ............................................................................. 7-1
Wiring Diagram .................................................................................................................. 7-1
Stri Circuits ...................................................................................................................... 7-2
Pag

1-1
Electrical Shock Hazard
Plug into a grounded 3-prong outlet.
Do not remove ground prong.
Do not use an adapter.
Do not use an extension cord.
Failure to ollow these instructions can
result in death, ire, or electrical shock.
Electrical Shock Hazard
Disconnect power be ore servicing.
Replace all panels be ore operating.
Failure to do so can result in death or
electrical shock.
Your sa ety and the sa ety o others is very important.
We have provided many important safety messages in this Job Aid and on the appliance. Always
read and obey all safety messages.
This is the safety alert symbol.
This symbol alerts you to hazards that can kill or hurt you and others.
All safety messages will follow the safety alert symbol and either the word
“DA GER” or “WAR I G.” These words mean:
All safety messages will tell you what the potential hazard is, tell you how to reduce the chance
of injury, and tell you what can happen if the instructions are not followed.
You can be killed or seriously injured i you don’t
immediately ollow instructions.
You can be killed or seriously injured i you don’t
ollow instructions.
ELECTRICAL POWER SUPPLY &
GROUNDING REQUIREMENTS
GENERAL
SAFETY FIRST

1-2
ELECTROSTATIC DISCHARGE
(ESD) SENSITIVE ELECTRONICS
ES problems are present everywhere. ES
may damage or weaken the electronic control
assembly. The new control assembly may ap-
pear to work well after repair is finished, but
failure may occur at a later date due to ES
stress.
• Use an antistatic wrist strap. Connect the
wrist strap to a green ground connection
point or unpainted metal in the appliance; or
touch your finger repeatedly to a green ground
connection point or unpainted metal in the
appliance.
• Before removing the part from its package,
touch the antistatic bag to a green ground
connection point or unpainted metal in the
appliance.
• Avoid touching electronic parts or terminal
contacts. Handle the electronic control as-
sembly by the edges only.
• When repackaging the failed electronic con-
trol assembly in an antistatic bag, observe
the above instructions.
Electrical Shock Hazard
Connect green ground wire to ground
screw.
Failure to do so can result in death or
electrical shock.

1-3
MODEL & SERIAL NUMBER DESIGNATIONS
MODEL NUMBER
SERIAL NUMBER
MODEL NUMBER K SB S 2 5 F K WH 0 0
PRODUCT GROUP
K = KitchenAid Brand
PRODUCT IDENTIFICATION
BR = Bottom Freezer Reversible Door
SB = Counter Depth Factory Installed Trim
SC = Counter Depth Architect Style
SF = Counter Depth Side By Side
SR = Side By Side Regular
TR = Top Freezer Reversible Door
MERCHANDISING SCHEME/SERIES
CAPACITY/CUBIC FOOT SIZE
MODEL FEATURES
YEAR OF INTRODUCTION
K = 2001
COLOR CODE
WH = White
ENERGY/POWER DESIGNATOR (NUMERIC)
0 = Original, 1 = 1st Change, 2 = 2nd Change, Etc.
ENGINEERING CHANGE (NUMERIC)
0 = Original, 1 = 1st Change, 2 = 2nd Change, Etc.
SERIAL NUMBER S L 3 0 10001
MANUFACTURING SITE
S = Fort Smith, AR
YEAR OF PRODUCTION
L = 2001
WEEK OF PRODUCTION
30th WEEK
PRODUCT SEQUENCE NUMBER

1-4
MODEL & SERIAL NUMBER LABEL
AND TECH SHEET LOCATIONS
The Model/Serial Number Label and Tech Sheet locations are shown below.
Model & Serial Number Location
(Re rigerator Compartment)
Base Grille
Tech Sheet
Location
(Behind Base
Grille)
Screw Screw

1-5
SPECIFICATIONS
Model Number KSBP25FKSS KSBS25FKBL KSBS25FKBT
Model Description
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Installed SS Panel Black Dispenser
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Dispensing Trim Model
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Dispensing Trim Model
Size-Configuration 25' Counter Depth 25' Counter Depth 25' Counter Depth
Cabinet Height (Floor To Top Of Cabinet) (in) 71 1/2 71 1/2 71 1/2
Overall Height (Floor To Top Of Hinge Covers) (in) 71 7/8 71 7/8 71 7/8
Cabinet Width (in) 35 1/2 35 1/2 35 1/2
Overall Depth (Including Hardware & Handles) (in) 29 3/8 29 3/8 29 3/8
Depth - Less Doors/Base Grille (Minimum Opening) (in) 23 5/8 2 4 2 4
Crated Weight (lbs) 360 360 360
Cabinet Color Black Black Biscuit
Cabinet Hinge Cover Color Black Black Biscuit
Cabinet Center Rail Color Black Black Biscuit
Cabinet Deck Rail Color Black Black Biscuit
Cabinet Base Grille/Color Black Black Biscuit
Cabinet Rollers Front/Rear Adjust Front/Rear Adjust Front/Rear Adjust
Refrigerant R134a R134a R134a
Energy Star Energy Star Energy Star Energy Star
Control Type Electronic ITC Electronic ITC Electronic ITC
Standard Warranty (Months) 12 12 12
Full Liner And Sealed System Warranty (Months) 60 60 60
Model Number KSBS25FKWH KSCS25FKSS KSFS25FKBL
Model Description
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Dispensing Trim Model
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Series Stainless Wrap Dispenser
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Freestanding Dispensing
Size-Configuration 25' Counter Depth 25' Counter Depth 25' Counter Depth
Cabinet Height (Floor To Top Of Cabinet) (in) 71 1/2 71 1/2 71 1/2
Overall Height (Floor To Top Of Hinge Covers) (in) 71 7/8 71 3/4 71 3/4
Cabinet Width (in) 35 1/2 35 1/2 35 1/2
Overall Depth (Including Hardware & Handles) (in) 29 3/8 29 1/2 29 3/8
Depth - Less Doors/Base Grille (Minimum Opening) (in) 2 4 2 4 23 5/8
Crated Weight (lbs) 360 360 360
Cabinet Color White Black Black
Cabinet Hinge Cover Color White Black Black
Cabinet Center Rail Color White Black Black
Cabinet Deck Rail Color White Black Black
Cabinet Base Grille/Color White Black Black
Cabinet Rollers Front/Rear Adjust Front/Rear Adjust Front/Rear Adjust
Refrigerant R134a R134a R134a
Energy Star Energy Star Energy Star Energy Star
Control Type Electronic ITC Electronic ITC
Standard Warranty (Months) 12 12 12
Full Liner And Sealed System Warranty (Months) 60 60 60

1-6
Model Number KSFS25FKBT KSFS25FKWH
Model Description
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Freestanding Dispensing
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Freestanding Dispensing
Size-Configuration 25' Counter Depth 25' Counter Depth
Cabinet Height (Floor To Top Of Cabinet) (in) 71 1/2 71 1/2
Overall Height (Floor To Top Of Hinge Covers) (in) 71 3/4 71 3/4
Cabinet Width (in) 35 1/2 35 1/2
Overall Depth (Including Hardware & Handles) (in) 29 3/8 29 3/8
Depth - Less Doors/Base Grille (Minimum Opening) (in) 23 5/8 23 5/8
Crated Weight (lbs) 360 360
Cabinet Color Biscuit White
Cabinet Hinge Cover Color Biscuit White
Cabinet Center Rail Color Biscuit White
Cabinet Deck Rail Color Biscuit White
Cabinet Base Grille/Color Biscuit White
Cabinet Rollers Front/Rear Adjust Front/Rear Adjust
Refrigerant R134a R134a
Energy Star Energy Star Energy Star
Control Type Electronic ITC Electronic ITC
Standard Warranty (Months) 12 12
Full Liner And Sealed System Warranty (Months) 60 60

1-7
REFRIGERATOR WARRANTY
ONE-YEAR FULL WARRANTY ON REFRIGERATOR
For one year from the date of purchase, when this refrigerator (excluding the water filter) is operated and main-
tained according to instructions attached to or furnished with the product, KitchenAid will pay for factory specified
replacement parts and repair labor costs to correct defects in materials or workmanship. Service must be pro-
vided by a KitchenAid designated service company. On models with a water filter: 30 day limited warranty on
water filter. For 30 days from the date of purchase, when this filter is operated and maintained according to in-
structions attached to or furnished with the product, KitchenAid will pay for replacement parts to correct defects
in materials and workmanship.
SECOND THROUGH FIFTH YEAR LIMITED WARRANTY
In second through fifth years from the date of purchase, KitchenAid will pay for replacement or repair of the re-
frigerator/freezer cavity liner (including labor costs) if the part cracks due to defective materials or workmanship.
Service must be provided by a KitchenAid designated service company. Also, KitchenAid will pay for factory
specified replacement parts and repair labor costs to correct defects in materials or workmanship in the sealed
refrigeration system. These parts are: compressor, evaporator, condenser, dryer, and connecting tubing. Service
must be performed by a KitchenAid designated service company.
SIXTH THROUGH TENTH YEAR LIMITED WARRANTY
In sixth through tenth years from date of purchase, KitchenAid will pay for factory specified replacement parts to
correct defects in materials or workmanship in the sealed refrigeration system. These parts are: compressor,
evaporator, condenser, dryer, and connecting tubing.
LIMITED LIFETIME WARRANTY
In second year through life of product from date of purchase, KitchenAid will pay for replacement of all SLI E N
LOCKTM oor Bins and SLI E N LOCKTM Can Racks due to defective materials or workmanship.
KitchenAid will not pay or:
1. Service calls to correct the installation of the refrigerator, to instruct you how to use the refrigerator, to re-
place house fuses or correct house wiring or plumbing, to replace light bulbs, or replacement water filters
other than as noted above.
2. Repairs when the refrigerator is used in other than normal, single-family household use.
3. Pickup and delivery. The refrigerator is designed to be repaired in the home.
4. amage resulting from accident, alteration, misuse, abuse, fire, flood, improper installation, acts of God, or
use of products not approved by KitchenAid or KitchenAid Canada.
5. Any food loss due to product failure.
6. Repairs to parts or systems resulting from unauthorized modifications made to the appliance.
7. Replacement parts or repair labor costs for units operated outside the United States or Canada.
8. In Canada, travel or transportation expenses for customers who reside in remote areas.
9. Any labor costs during the limited warranty period.
KITCHENAID AND KITCHENAID CANADA SHALL NOT BE LIABLE FOR INCIDENTAL OR CONSEQUEN-
TIAL DAMAGES.
Some states or provinces do not allow the exclusion or limitation of incidental or consequential damages, so this
exclusion or limitation may not apply to you. This warranty gives you specific legal rights, and you may also have
other rights which vary from state to state or province to province.
Outside the 50 United States and Canada, this warranty does not apply. Contact the authorized KitchenAid
dealer to determine if another warranty applies.
If you need service, first see the “Troubleshooting” section of the Use and Care Guide. After checking “Trouble-
shooting,” additional help can be found by checking the “Assistance or Service” section, or by calling the
KitchenAid Customer Interaction Center, 1-800-422-1230 (toll-free), from anywhere in the U.S.A. In Canada,
contact the designated KitchenAid Canada Appliance service company, or call 1-800-807-6777.

1-8
— NOTES —

2-1
LEVELING THE REFRIGERATOR
IMPORTANT: All four leveling legs must con-
tact the floor to support and stabilize the full
eight of the refrigerator.
Base Grille Removal
1. Open the refrigerator doors.
NOTE: Do not remove the Tech Sheets fas-
tened behind the grille.
2. Remove the scre s from the base grille
and remove the grille.
Adjustin The Rollers
The roller adjusting bolts are located behind
the base grille. The refrigerator has four adjust-
able rollers: t o in front, and t o in the rear.
There are t o sets of roller adjusting bolts
found at the base of the refrigerator on each
side. The rear leveling bolt (1) is yello , and
the front leveling bolt (2) is silver.
1. Use a 1/2″ (12.70 mm) socket rench to
adjust the leveling bolts. Turn the leveling
bolt to the right to raise that side of the
refrigerator, or turn the leveling bolt to the
left to lo er that side. It may take several
turns of the leveling bolts to adjust the tilt
of the refrigerator.
2. Adjust the front leveling bolt so that the top
of the refrigerator is parallel ith the cabi-
net above the refrigerator.
For standard cabinets, leave approximately
1/8″ (3.18 mm) gap bet een the top hinges
and the cabinet.
For full-overlay cabinets, leave a 1/4″ (6.35
mm) gap for leveling.
If you do not have a cabinet above the
refrigerator, adjust the refrigerator to make
it level.
1
2
NOTE: Be careful not to unscre the leveling
bolts too much hen lo ering the refrigerator.
The bolt head ill start to come a ay from the
refrigerator hen it is in the lo est position. If
the bolt comes out of the rear roller bracket, the
compartment access cover on the back of the
refrigerator ill have to be removed to reinstall
the bolt.
3. Adjust the rear leveling bolt and level the
refrigerator ith the side cabinets, or ith
the cabinet end panels.
4. If needed, use the four leveling bolts to
raise the refrigerator to close the gap
bet een the refrigerator top hinge, and
the cabinet opening. Check to make sure
that all four rollers still touch the floor, and
that the cabinet doors above the refrigera-
tor open all the ay.
Cabinet
Front Of
Refrigerator
INSTALLATION INFORMATION

2-2
— NOTES —

3-1
OVERVIEW
The KitchenAid Counter Depth Refrigerator
Constant Flow Temperature Management Sys-
tem uses two thermistors to monitor tempera-
ture changes inside the refrigerator and freezer
compartments The electronic control man-
ages the operation of the variable capacity
compressor (VCC), a variable speed evapora-
tor fan motor, and a variable position air door
The air door allows independent temperature
control of the refrigerator and freezer compart-
ments
The electronic control seeks the most efficient
means possible to maintain temperatures as it
controls the operation and speed of the com-
pressor and the evaporator fan motor Higher
fan speed is used before increasing the com-
pressor speed to minimize power consump-
tion A nearly constant run time is sought at the
lowest possible fan and compressor speed
Warmer
Water
Filter
Power
On/Off
Warmer
Cooler
Freezer Refrigerator
Cooler
46
40.4
38.7
37
35.3
33.6
31.9
8
3.4
1.7
0
–1.7
–3.4
–5.1
THE ELECTRONIC CONTROL PANEL
NOTE: The illustration above shows the actual
temperature that is associated with each corre-
sponding LED
Freezer temperatures can be set from 8°F to
–5°F (–13°C to –21°C) Refrigerator tempera-
tures can be set from 46°F to 32°F, (8°C to
0°C)
The Adaptive Defrost Control (ADC) portion of
the electronic control utilizes “pulsed defrost”
technology to perform the defrost function (see
page 3-4)
The electronic control monitors the water valve
for total elapsed time and gallons of water
used The Water Filter Indicator (WFI) LED
changes color to indicate that the filter needs to
be replaced
Pressing the Temperature Up or Down adjust-
ment keys will change the refrigerator and
freezer settings One of seven (7) LEDs light to
display the refrigerator and the freezer set-
tings
THEORY OF OPERATION

3-2
Freezer Temperature Control
Temperature Decreasing
When the freezer temperature begins to de-
crease, the process will reverse. The compres-
sor speed decreases, followed b the evapo-
rator fan speed.
Refrigerator Temperature Control
Temperature Increasing
When the refrigerator calls for cooling while
the freezer is satisfied, the air door begins to
open, and the evaporator fan starts to run at
minimum speed. If the temperature continues
to rise, the air door will continue to open. If the
temperature continues to rise after the air door
is full open, the evaporator fan speed will
graduall increase to a maximum of 3000 rpm.
If the temperature continues to rise, the com-
pressor starts to run, or if it has alread been
running, begins to increase in speed.
Refrigerator Temperature Control
Temperature Decreasing
As the refrigerator temperature approaches the
selected setting, the control compares the tem-
peratures in both compartments to determine
which compartment will control the fan speed.
If the freezer is further from the selected tem-
perature setting, it controls the fan speed, and
the air door begins to close, thus reducing the
airflow to the refrigerator.
If the freezer is satisfied, the air door remains
open, and the fan speed begins to decrease.
When the selected temperature setting is
reached, the air door closes.
TEMPERATURE CONTROL
The electronic control checks the resistance of
the thermistors, and compares it to both the
customer temperature settings and the last
thermistor reading taken. This information is
used to determine when to begin a cooling
operation, and if a change is necessar in the
damper setting, or the evaporator fan or com-
pressor speed.
When a warm refrigerator is first put into a
cooling mode, the air door partiall opens, and
the compressor and evaporator fan motors
start to run at maximum rpm. The air door will
graduall move to its full open position.
As the actual temperature in the refrigerator
nears the selected temperature setting, the
electronic control compares the temperatures
in both compartments. The compartment that
has the greatest need for cooling, will control
the speed of the evaporator fan motor.
Freezer Temperature Control
Temperature Increasing
When the freezer calls for cooling, the com-
pressor begins to run at minimum rpm, (see the
chart on page 3-3), and the evaporator fan
begins to run at 2000 rpm. The compressor
and evaporator speeds are continuousl up-
dated. Speed changes are made based on:
• The difference between the actual tempera-
ture and the selected temperature settings.
• The rate of temperature change.
If the temperature increases 4°F above the
selected temperature setting, the evaporator
fan speed begins to graduall increase. The
evaporator fan motor reaches the maximum
speed of 3000 rpm at 5°F above the selected
temperature setting, and the compressor speed
begins to graduall increase. A maximum com-
pressor speed of 4500 rpm will be reached at
9°F above the selected temperature setting.

3-3
COMPRESSOR
The main control board supplies a 5 vdc, peak-
to-peak square wave, at 54 to 150 Hz, to the
inverter board. A standard VOM will read ap-
proximatel 2.5 vdc. The inverter board sup-
plies the variable capacit compressor with
three-phase 230 vac. Var ing the frequenc
to the inverter board, and not the voltage,
changes the speed of the compressor. The
compressor can run at speeds of 1620 to 4500
rpm.
NOTE: It is not necessar , nor is it recom-
mended, to test the output of the inverter board.
While the compressor is running, its speed is
continuousl updated. Speed is determined
after anal zing two factors:
• The difference between the actual tempera-
ture and the selected temperature settings.
• The rate of temperature change.
Minimum compressor speed is based on the
freezer’s selected temperature setting, as
shown in the following chart.
The compressor generall c cles on and off
according to the cut-in and cut-out tempera-
tures of the freezer, however, the refrigerator
can turn on the compressor if the evaporator
fan is at maximum speed and the refrigerator
temperatures are not dropping.
Freezer Temperature Compressor
Setting Minimum Speed
#1 - #5 1620 rpm
# 6 1800 rpm
# 7 2200 rpm
COMPRESSOR PROTECTION
To protect the compressor and maintain effi-
cienc , minimum compressor off time is pro-
grammed into the control. When the compres-
sor turns off, a minimum of 7 minutes must
elapse before allowing a restart.
The inverter board utilizes a current limiting
device and thermal protection that eliminates
the need for a compressor mounted thermal
protector.
EVAPORATOR FAN MOTOR
The evaporator fan motor is a 12 vdc, variable
speed motor. The motor has four wires:
• A blue wire provides feedback to monitor the
speed of the motor.
• A red wire provides a constant 12 vdc.
• A ellow wire provides a variable voltage of
between 5 vdc and 17 vdc to control the
motor speed from 2000 to 3000 rpm.
• A white wire provides a common return.
EVAPORATOR FAN &
AIR DOOR DELAY
After defrost, an evaporator fan dela prevents
unnecessar movement of warm, moist air
through the refrigerator, b chilling the evapo-
rator prior to starting the fan. Immediatel af-
ter defrost drip time, the compressor starts at
4500 rpm, but the evaporator fan is dela ed
for 8 minutes. The air door remains closed for
8 minutes following defrost.
AIR DOOR
The air door is driven b a reversible DC
stepper motor. The motor operates on a 12
vdc, peak-to-peak square wave. Voltage is
delivered to the air door in a series of short
pulses. It is not possible to obtain a reliable
voltage reading with a VOM.
Separate windings are used to move the air
door open or closed. The door can be in an
one of 1800 positions from 0 to 90 degrees.
The air door is used to fine-tune the airflow to
the refrigerator.

3-4
The refrigerator temperature determines the
opening of the air door. When the refrigerator
requires cooling, if the evaporator fan motor is
alread running for the freezer, the air door
partiall opens, and then adjusts, if necessar .
While the refrigerator is cooling, the door will
be adjusting continuousl to maintain or re-
cover refrigerator temperature.
ADAPTIVE DEFROST
The adaptive defrost control allows the unit to
enter a defrost mode onl when it is needed.
When powered up for the first time, the control
initiates a defrost c cle after 8 hours of com-
pressor run time. B monitoring the duration of
defrost heating time and compressor run time,
the control will continuousl adapt the time
between defrosts to optimize efficienc . Time
between defrost periods will var between 8
and 100+ hours.
Defrost will occur immediatel when the com-
pressor has run at 4000 rpm or greater for 1
hour, and 8 hours have elapsed since the last
defrost.
PULSED DEFROST
For the first 7 minutes of defrost, the heater is
on continuousl . It will then c cle off for 1
minute, and back on for 2 minutes. The heater
will continue to c cle at this ratio until the
bimetal opens, or until 33 minutes has elapsed.
At this point, heat is discontinued, and a
4-minute “drip time” begins. This allows the
water to drain before the unit returns to a
cooling mode. Maximum defrost time, (pulsed
heat on/off time + drip time) is 37 minutes.
When entering a defrost c cle, if the bimetal is
open, the time to defrost is reset to 8 hours, and
the control will time through the entire 37 minute
defrost period. During diagnostics this will al-
low a technician time to look for heater opera-
tion, and if necessar , b pass the bimetal.
POWER INTERRUPTION
After a power interruption, the following events
will occur:
• The unit returns to the same operating mode
and settings in use prior to the power inter-
ruption. If the unit was off, it remains off.
• Initiall , the compressor, evaporator fan, and
condenser fan motors will be off.
• The air door will close, and then adjust to the
proper opening. The evaporator fan starts
when the air door opens.
• The adaptive defrost control resets the com-
pressor run time counter to 0, and if the
freezer is above 20°F, the time to defrost is
set to 8 hours.
• If the freezer temperature is below 12°F, the
compressor starts after a dela of 7 minutes.
If the freezer temperature is above 12°F, the
compressor starts immediatel .
FAILURE DEFAULTS
In the event of a thermistor, or ke pad failure,
the control uses one of the following default
modes, which will continue until the failure is
corrected.
Refrigerator Thermistor
If the control senses an open or a shorted
thermistor, the air door and the evaporator fan
motor will begin to operate on a timed on and
off c cle, based on current selected tempera-
ture settings. The evaporator fan motor will run
when the air door is open.
At mid-settings of 37°F / 0°F, the air door will
open for 16 minutes, and close for 30 minutes.
Setting the freezer colder, or the refrigerator
warmer, will reduce the door-open time. Set-
ting the freezer warmer, or the refrigerator
colder, will increase the door-open time.

3-5
Freezer Thermistor
If the control senses an open or a shorted
thermistor, the compressor and the evaporator
fan motor will begin to operate on a timed on
and off c cle. The c cle time is based on
current selected temperature settings.
At mid-settings of 37°F / 0°F, the compressor
and the evaporator fan motors will run for 35
minutes, and be off for 25 minutes. Setting the
freezer colder will increase the run time. Set-
ting the freezer warmer will decrease the run
time.
The compressor will run at minimum speed.
The evaporator fan will also run at minimum
speed, unless the refrigerator compartment
requests a higher speed.
Keypad
If the control detects that the ke pad is not
working, it reverts to the default temperature
settings of 37°F in the refrigerator, and 0°F in
the freezer.
Evaporator Fan Motor
If the evaporator fan motor malfunctions, the
compressor will run at 4500 rpm for an indefi-
nite period, except during the defrost periods.
ELECTRONIC CONTROL
THERMAL SHUTOFF
The electronic control utilizes an on-board ther-
mistor to shut the compressor off if the tem-
perature rises above 160°F (71°C). When the
temperature drops to 130°F (55°C), the com-
pressor returns to normal operation. This c cle
continues indefinitel until the cause of the high
temperature has been corrected.
AIR CIRCULATION
In order to ensure the proper refrigerator and
freezer compartment temperatures, air must
be able to flow between the two sections.
Air enters the bottom of the freezer compart-
ment and moves up through the evaporator.
Some of the cooled air from the evaporator is
directed back into the freezer, and the rest
goes into the refrigerator through the motor-
ized air door. The refrigerator air then returns to
the freezer through the bottom air return (see
the illustration below).
It is important not to block an of the vents with
food items. If the vents are blocked, airflow will
be restricted, and the temperature manage-
ment s stem will not function properl .
IMPORTANT: Because air circulates between
both sections, an odors formed in one section
will transfer to the other. Keep both sections
clean, and wrap or cover foods tightl to pre-
vent odors from occurring.

3-6
NOTES