Maytag Gemini MER6770AAW User manual

Maytag
Gemini™
Range
Service Manual
16010107
Issued10/00

©2000 Maytag Appliances Sales Company
16010107 Introduction i
INTRODUCTION
The manual is printed in a loose format and is divided into sections relating to a general
group of components and/or service procedures. Each section is further subdivided to
describe a particular component or service procedure.
The subdividing of the subject matter, plus the loose leaf form, will facilitate the updating of
the manual as new revised components are added or new models are introduced.
Each page of the manual will be identified in the lower, left and right-hand corners, and as
new or revised pages are published, the manual can easily be updated by following the filing
instructions on the cover letter of the supplement.
This service manual is a valuable tool and care should be taken to keep it up-to-date by
promptly and proper filing of subsequent pages as they are used.
MODELS COVERED IN THIS MANUAL:
MER6770AAW
MER6770AAB
MER6770AAC

©2000 Maytag Appliances Sales Company
16010107 Introduction ii

©2000 Maytag Appliances Sales Company
16010107 Contents iii
CONTENTS
INTRODUCTION............................................................................................................................... i
CONTENTS..................................................................................................................................... iii
SECTION 1. GENERAL INFORMATION ....................................................................................1-1
SECTION 2. ELECTRICAL COMPONENTS & TESTING...........................................................2-1
SECTION 3. COMPONENT ACCESS ......................................................................................... 3-1
EXPLODED VIEW ......................................................................................................................3-1
MAIN TOP .................................................................................................................................. 3-2
ELEMENTS.................................................................................................................................3-2
Ceran Element ......................................................................................................................3-2
Bake Element ........................................................................................................................3-3
Broil Element........................................................................................................................ 3-3
Oven Sensor.........................................................................................................................3-3
Oven Cavity Components (Electric) ...................................................................................3-4
Convect Fan Motor and Blade (Electric) ............................................................................3-5
ELECTRONIC CLOCKAND OVEN CONTROL .........................................................................3-6
INFINITE SWITCH (Current Sensing) .......................................................................................3-6
Signal Lights......................................................................................................................... 3-7
"Hot Surface" Light ...............................................................................................................3-7
Oven Light Replacement .....................................................................................................3-7
HI-LIMIT THERMOSTAT............................................................................................................3-8
OVEN DOOR(S).........................................................................................................................3-8
UPPERDOOR ............................................................................................................................3-9
LOWER DOOR ......................................................................................................................... 3-10
Lower Latch Assembly ......................................................................................................3-10
LOWER LATCH ASSEMBLY....................................................................................................3-11
Oven Door Hinge ...............................................................................................................3-11
LEVELINGLEGS.......................................................................................................................3-12
CONVENIENCE OUTLET (Canadian Models Only)...............................................................3-12
SPECIFICATIONS.....................................................................................................................3-12
OVEN RACKS ..........................................................................................................................3-12
RACK POSITIONS ................................................................................................................... 3-13
HALF RACK ACCESSORY ......................................................................................................3-13
SECTION 4. ELECTRICAL ...........................................................................................................4-1
TOASTING CIRCUIT (Upper Oven Only) .................................................................................4-1
OVEN CIRCUITS ........................................................................................................................4-1
SURFACE ELEMENTS - CERAN ...............................................................................................4-2
DUEL ELEMENT.........................................................................................................................4-2
PROBE, SENSOR / BOTH OVENS............................................................................................4-2
HOT SURFACE LIGHTS.............................................................................................................4-3
SURFACE INICATOR LIGHTS....................................................................................................4-3
TRANSFORMER, STEPDOWN (12V) .......................................................................................4-4

©2000 Maytag Appliances Sales Company
16010107 Contents iv
SURFACE ELEMENT SWITCH ..................................................................................................4-4
DUAL ELEMENT SWITCH ......................................................................................................... 4-4
ELECTRICAL CONNECTIONS/VOLTAGE.................................................................................4-5
SECTION 5. TROUBLESHOOTING............................................................................................ 5-1
GEMINI DOUBLE OVEN CONTROLS.......................................................................................5-1
FAULT CODES ...........................................................................................................................5-2
RELAY BOARD ..........................................................................................................................5-3
TROUBLESHOOTING GUIDE....................................................................................................5-4
PARTS LIST................................................................................................................................5-6
FAULT IDENTIFICATIONS SUMMARY.....................................................................................5-7
SECTION 6. WIRING DIAGRAMS..............................................................................................6-1

©2000 Maytag Appliances Sales Company
16010107 Section 1. General Information 1-1
SECTION 1. GENERAL INFORMATION
Bake: There will be two separate bake keys,
one for each oven. When the upper oven is
chosen there will be a rapid preheat
activated which turns both elements on. If
the lower oven is selected the elements will
cycle at the normal rate. The normal rates
for the bake functions in both ovens are: 6
seconds for the broil element, followed by 54
seconds for the bake element.
Broil: There will be two separate broil keys,
one for each oven. The HI broil function
controls the broil element at 100%, the LO
broil is controlled at 80% on time of a 60
second duty cycle. HI broil will be
maintained to reach a maximum
temperature of 550ºF, LO boil will be
maintained at a maximum of 450ºF.
Toasting: Available in upper oven only.
Toasting has a maximum allowable time of
10 minutes and maximum temperature of
550ºF. Toasting is only available when the
lower oven is not in use. If chosen during
lower oven operation the display will scroll
an information message regarding use.
Keep Warm: The keep warm function
controls only the bake element and is
available in the upper oven only. Allowable
temperature range is 145 to 190ºF.
Clean: Only one oven is permitted to be
cleaned at a time. Both ovens will lock
during clean cycle. The clean cycle controls
both the broil and the bake element, the broil
element is on 100% for the first 40 minutes
of the cycle followed by the bake element on
100% for the duration of the cycle. The bake
element is cycled once the clean
temperature of 865º is reached.
Motorized Door Lock: A 3 RPM motor is
used on the door lock assemblies, with each
assembly having a locked and unlocked
switch. The motor will only run when a
clean cycle is chosen and the door actuated
switch is in the closed position.

©2000 Maytag Appliances Sales Company
16010107 Section 1. General Information 1-2

©2000 Maytag Appliances Sales Company
16010107 Section 2. Electrical Components & Testing 2-1
SECTION 2. ELECTRICAL COMPONENTS & TESTING
ELECTRICAL TEST EQUIPMENT
The equipment required to service Maytag
products depends largely upon the condition
you encounter. Locating a malfunction will
often require the use of electrical testing
equipment such as:
Analog Test Meter
can be used to check for
open or closed circuits,
measure resistance, AC
and DC volts, and tem-
perature.
Clamp-On Ammeter
can be used to detect
shorts. Over-
loads on the
circuit breaker
or fuse can be
traced to either
the dryer or circuit
breaker by check-
ing the dryer
current draw.
Description Part Number
Analog Test Meter 20000005
Digital Watt/Amp/Volt/Ohm/
Temperature Meter 20000019
Clamp-On Ammeter 20000002
AC Voltage Sensor 20000081
AC Voltage Sensor
can be used to alert you
if AC voltage is present so
proper safety precautions can
be observed. The tip of the sensor
will glow bright red, if voltage is be-
tween 110-600 volts AC.
Digital Watt/Amp/Volt/Ohm/Temperature
Meter
Measures power (wattage), AC/DC volts, AC/
DC amps, temperature (C & F) OHMS resis-
tance, continuity and capacitance. Features
large LCD display w/backlight and analog
bar graph to show tendencies. Includes: AC
power adaptor for measuring wattage and
meter leads.

©2000 Maytag Appliances Sales Company
16010107 Section 2. Electrical Components & Testing 2-2

©2000 Maytag Appliances Sales Company
16010107 Section 3. Component Description 3-1
SECTION 3. COMPONENT ACCESS
EXPLODED VIEW

©2000 Maytag Appliances Sales Company
16010107 Section 3. Component Description 3-2
As a general rule, the appliance should
ALWAYS be disconnected from power
source before servicing appliance or
replacing component parts. Failure to
disconnect the power increases the
likelihood that a servicing error or mistake
will result in serious or fatal injuries.
MAIN TOP
To Raise Ceran Cooktop
When cool open the door and remove the
two screws securing the cook top to the
frame. Once the screws are removed raise
cook top and slide forward slightly. With the
cook top forward disconnect the wire
harness and remove the cooktop.
ELEMENTS
Ceran Element Cooktop
Cooking areas are identified by patterns in
the Ceran surface. The elements consist of
coil(s) contained in the element housing.
Power to the element (240 volts) is provided
and controlled by an infinite switch. Each
heating element is equipped with a
temperature limiter, which prevents heat
surges and ensures that the heating
elements will not overheat. The element and
temperature limiter is available as a
complete unit or individual parts.
When a cooking area is turned ON, the coil
element under the cook top will heat up and
glow. The element will cycle on and off to
maintain the heat setting. When the element
cycles on, it is normal to see a red glow
through the smooth top.
Note: It is normal for the element to cycle
when set on the high setting.
To Remove Element:
1. Disconnect the appliance from power
source before servicing.
2. Remove the two screws securing the
main top to the frame.
3. Lift up slightly and slide the main top
forward to access the wire harness.
Disconnect the harness.
4. Lift the top off and lay aside securely with
under side up.
5. Remove the screws securing element to
main top.
6. Disconnect wiring to element and
replace element.
7. Reverse procedure to reinstall.
To Remove Glass TopAssembly
1. Disconnect the appliance from power
source before servicing.
2. Remove two (2) screws securing glass
top to frame. The screws are located in
the front left and right corners with the
door open.
3. Grasp front edge of cooktop and slide out
slightly. With the top moved forward
disconnect the wiring harness.
4. Lift the top off the unit and lay aside
securely.
5. Reverse the procedure to reinstall.
Ceran Element
•Left front and right rear element wattage:
208/240 volts @ 900/1200 watts.
Approximately 48Ω.
•Left rear element wattage: 208/240 volts
@ 1580/2200 watts. Approximately 27Ω.
•Dual element wattage: 208/240 volts @
1580/2200 watts. Approximately 27Ωfor
the outer element. 208/240 volts @ 580/
750 watts. Approximately 73Ωfor the
inner element.

©2000 Maytag Appliances Sales Company
16010107 Section 3. Component Description 3-3
Bake Element
Element Wattage: 208/240 volts @ 2250/3000
watts. Approximately 19Ω
The bake function controls the Bake and
Broil heating elements. During a Bake cycle,
the Broil element will be on 6 seconds of a
60-second duty cycle, and then the Bake
element will be on the remaining 54
seconds. The Bake and Broil elements will
be staged with the exception of the rapid
preheat. In the rapid preheat, available when
the upper oven is used alone, the bake and
broil elements will be on at 100% until
temperature is reached. Once temperature
is reached, the elements will cycle as
outlined above.
Note: The Bake element will be the first
element to turn on at the beginning of any
conventional bake cycle.
ToAccess Bake Element:
1. Disconnect the appliance from power
source before servicing.
2. Remove lift off door for more
accessibility.
3. Remove four (4) screws securing bake
element to back of oven cavity.
4. Gently pull element through cavity wall
until terminals can be accessed.
5. Disconnect wiring.
6. Remove/replace element as necessary.
7. Reverse procedure to reinstall.
Broil Element
The broil function controls only the broil
element. The bake element is inactive
during a broil cycle. During a broil cycle, the
control will monitor the oven temperature
and cycle the broil element on and off to
obtain the selected temperature.
To Access Broil Element:
1. Disconnect the appliance from power
source before servicing.
2. Remove lift off door for more
accessibility.
3. Remove broil support brackets (2) and
remove screws securing broil element to
back oven.
4. Gently pull element through cavity wall
until terminals can be accessed.
5. Disconnect wiring.
6. Remove/Replace element as necessary.
7. Reverse procedure to reinstall.
Oven Sensor
The oven sensor is located inside the oven
cavity, attached to the rear wall of the cavity.
As the oven temperature increases, the
resistance of the oven sensor increases. The
resistance is measured by the electronic
control to determine the oven temperature.
ToAccess Oven Sensor:
1. Disconnect the appliance from power
source before servicing.
2. Open oven door and remove two (2)
screws securing sensor to oven cavity.
Gently pull through cavity wall.
3. Disconnect the oven sensor at the
connector blocks and remove/replace as
necessary.
4. Reattach the connector blocks and
reassemble.

©2000 Maytag Appliances Sales Company
16010107 Section 3. Component Description 3-4
Also shown here are the screws that secure the
bake and broil elements.
Oven Cavity Components (Electric)
Open or remove the oven door. The
following components are accessible:
• Racks
• Oven Sensor
• Broil Element
• Convect Fan Cover
• Bake Element
Convection Fan (Electric)
Remove six screws (as shown) from the
perimeter of the convection fan cover. This
will loosen the cover, but it cannot be
removed easily without positioning it to
clear the rack guides. Care should be used
when moving parts and tools around inside
the oven cavity to avoid marring or chipping
the procelain surfaces.
Three screws (shown) secure the convection
fan mounting plate, remove these, to allow
access to the motor and connectors.
BakeElement
Convect
Fan
Cover
Convect
Fan
Sensor Broil Element
Screws
Screws
Screws
Screws

©2000 Maytag Appliances Sales Company
16010107 Section 3. Component Description 3-5
After the convect fan mounting plate is
removed, motor connectors, motor, motor
mount and insulation is accessible. Motor
connectors are also exposed by removing
the back panel (see range back removal).
The convect fan blade is attached to the
motor’s “D” shaft using a hex set screw.
The fan blade must be loosened and taken off
the motor shaft before the motor can be
removed. The motor mounting screws are
found on the front side of the convect fan
assembly. When reassembling, be sure to
reinstall the small piece of insulation under the
motor mount. The insulation provides sound
dampening and prevents heat loss. When
reinstalling the convect fan blade, be sure that
the blade has adequate clearance at all points
around the mounting plate. The blade should
“stand off” approximately 1/8” with very little
apparent warping.
Note: When reinstalling the convect assembly, be sure to
check that no loose insulation is visible in the fan area
or anywhere in the oven cavity.
Convect Fan Motor and Blade (Electric)
MotorConnectors
Motor Mount
Motor
Insulation
Mounting Screws
Hex Head Set Screw

©2000 Maytag Appliances Sales Company
16010107 Section 3. Component Description 3-6
ELECTRONICCLOCKANDOVEN
CONTROL
To Gain Access To Electronic Oven Control
1. Disconnect the
appliance from
power source
before servicing.
2. Remove two screws
securing backguard
panel to the end caps.
3. Remove two (2) screws securing
backguard panel to backguard housing.
(Screws located between control panel
and main top).
4. Lift backguard panel up, tilt forward, and
lay panel on protected surface of main
top for servicing.
5. Remove two (2) screws securing control-
mounting plate to backguard.
6. Remove four (4) screws securing control
to control mounting plate.
7. Disconnect wiring and remove/replace
control.
8. Reverse procedure to replace.
INFINITE SWITCH (Current Sensing)
This unit is equipped with controls that
provide an infinite choice of settings from
LOW to HIGH. The control can be set on any
of the numbered settings. To operate, push
in and turn control knob to the desired
setting.
Note: The infinite switch is a current
sensing switch.
The infinite switch is a rotary switch, which
controls the power dissipated by a heating
element. A heater-bimetal opens and closes
the cycling contacts, which applies and
removes voltage from the heating element.
Control is attained by regulating the ratio of
the time between the opening and closing of
the contacts. This is usually referred to as
input percentage and is controlled by a cam,
which can provide virtually any infinitely
adjustable performance. This performance
is assured when the switch is subjected to
elevated ambient temperatures through
automatic temperature compensation.
The infinite switch stems are color coded for
identification. The silver colored stem
controls the left front and right rear element,
the silver colored stem with a red dot
controls the left rear, and the brass colored
stem controls the right front element.
Amperage is rated at 3-15.5A range +/- 10%.
Note: When replacing the infinite switch,
the switch must be matched to the element.
ToAccess Control:
1. Disconnect the appliance from power
source before servicing.
2. Remove control knobs.
3. Remove two screws from backguard
panel securing panel to housing.
4. Remove two screws securing backguard
panel to end cap.
5. Lift backguard panel up, tilt forward, and
lay panel on protected surface on main
top for servicing.
6. Remove two (2) mounting screws
securing infinite switch to backguard
panel.
7. Disconnect wiring and remove/replace
control.
8. Reverse procedure to replace.

©2000 Maytag Appliances Sales Company
16010107 Section 3. Component Description 3-7
Signal Lights
Range is equipped with two signal lights to
indicate when a surface element is on. The
light will remain on until the element is
turned off. After a cooking operation, be
sure element and signal light is off.
The signal lights are located on the
backguard panel and may be accessed from
the backside of the panel when removed.
The red indicator lens pop in and out, and
the light slides into a lock position. Reverse
the procedure to remove.
“Hot Surface”Light
The Gemini Range is equipped with a Hot
Surface Light. This red light will turn on to
indicate that the cooking area is hot and will
remain on until the area has cooled.
The switch is located in the front center of
the burner box, and may be accessed by
removing the main top.
To Access Hot Surface Light:
1. Disconnect the appliance from power
source before servicing.
2. Open oven door and remove the screws
securing the main top to the frame.
3. Slide the top forward and disconnect the
wire harness.
4. Lift the top off and lay on a protected
surface with under side up.
5. Release the tabs securing the switch to
the top. Once the tabs are released the
switch can be removed.
6. Reverse procedure to replace.
Oven Light Replacement
The oven light used on the Gemini is a 12
volt 10 Watt Halogen bulb. The light
automatically comes on when the door is
opened or activation may occur via the light
pad when the door is closed. The light will
not operate during a clean cycle. The oven
light will automatically come on one minute
before the end of a clock controlled cooking
operation.
To Replace Oven Light Bulb:
1. Disconnect power to the range.
2. Open oven door and locate oven light.
3. Remove the lens cover to gain access to
bulb.
4. Carefully remove the old bulb by pulling
straight out of ceramic base.
NOTE: To avoid damaging the bulb and
decreasing the life of the bulb, do not touch
the bulb with bare hands or fingers. Hold
with a cloth or paper towel.
5. Push new bulb prongs straight into small
holes of ceramic base.
6. Replace bulb cover by snapping into
place.
7. Reconnect power to range and reset
clock.
Bulbspecifications
G4 Type Halogen Bi-Pin 10 w -12V

©2000 Maytag Appliances Sales Company
16010107 Section 3. Component Description 3-8
HI-LIMIT THERMOSTAT
The HI-Limit Thermostat is mounted to
range main back. The purpose of this
thermostat is to break line voltage to oven
control in case of a runaway temperature.
Range may be removed from cabinetry for
rear serviceability.
Thermostat Replacement
1. Disconnect the appliance from power
source before servicing.
2. Slide unit out of installation.
3. Remove screws securing main back
shield and remove shield.
4. Remove two (2) screws securing
thermostat to range main back.
5. Disconnect wiring.
6. Replace in reverse order.
OVEN DOOR(S)
Do not place excessive weight on an open
oven door or stand on an opened door as, in
some cases, it could cause the range to tip
over, breakage of the door, or serious injury.
Both the upper and lower oven doors are
removable.
To Remove Lift-Off Door:
Open door to stop position. In stop position
door is open approximately 4”. Grasp door
as illustrated. Lift up evenly until door clears
the hinge arms.
DO NOT USE DOOR HANDLE TO LIFT
DOOR.
To Replace:
1. Grasp door at each side.
2. Align slots in the door with the hinge
arms on the range.
3. Slide the door down onto the hinge
arms until the door is completely
Contacts normally closed
Close Temperature - 250 ± 11ºF
Open Temperature - 300 ± 8ºF
CAUTIONS:
• Do not attempt to open or close door
or operate oven until door is properly
replaced.
• Hinge arms are spring mounted and
will slam shut if accidentally hit.
Never place hand or fingers between
the hinges and the front oven frame.
You could be injured if hinge snaps
back.

©2000 Maytag Appliances Sales Company
16010107 Section 3. Component Description 3-9
seated on the hinges. Push down on
the top corners of the door to
completely seat door on hinges. Door
should not appear crooked.
NOTE: The oven door on a new range
may feel “spongy” when it is closed.
This is normal and will decrease with
use.
To Disassemble Door:
1. Open door to the stop position and lift
door off hinges. Remove door and lay
on protected surface, liner side up.
2. Remove three (3) screws securing the
doorframe to the liner at the bottom.
3. Remove two (2) side screws securing
doorframe to door liner.
4. Remove four (4) screws securing the
door trim at the top.
5. Slide the doorframe and glass off liner
from the bottom.
6. Remove four (4) screws securing the
door handle to the door liner. (Two on
the sides and two in front).
7. Remove two (2) screws securing door
baffle to liner.
8. Remove four (4) screws securing door
baffle to window pack. Remove baffle.
9. Remove insulation wrap.
10. Remove four (4) screws securing window
pack to liner. Window pack comes out as
an assembly.
11. Door gasket can be replaced without
door being disassembled by pulling
gasket out of bottom insert of door. The
gasket is secured with clips inserted into
door liner.
UPPERDOOR

©2000 Maytag Appliances Sales Company
16010107 Section 3. Component Description 3-10
LOWERDOOR
To Replace Lock Assembly
1. Disconnect the appliance from power
source before servicing.
2. Open oven door or remove for
convenience.
3. Remove main top and slide forward.
Disconnect wire harness. (See Top
Removal).
4. Lift top off and lay aside securely.
5. Remove two (2) screws securing lock
assembly to oven frame in front.
6. Disconnect wiring.
7. Remove two (2) screws securing lock
assembly to frame.
8. Slide assembly out.
9. Reverse procedure to reinstall.
Lower Latch Assembly
1. Disconnect the appliance from power
source before servicing.
2. Remove main top assembly as described
previously and lay aside securely.

©2000 Maytag Appliances Sales Company
16010107 Section 3. Component Description 3-11
3. Remove main top and slide forward.
Disconnect wire harness. (See Top
Removal).
LOWER LATCHASSEMBLY
1. Disconnect the appliance from power
source before servicing.
2. Remove main top as outlined
in main top removal.
3. Remove the screws
securing the side
panel at the top and
back of frame.
4. Remove the screws
securing the rear
panel to frame. Remove rear panel.
5. Slide side panel away from the frame at
rear and lift out of the slots in front.
Remove side panel.
6. Release the bands, securing the
insulation wrap, at the bottom.
7. Slide the insulation wrap back.
Note: This will aid in guiding the latch
assembly in and out.
8. Disconnect the wiring from the lock
switches at the rear.
9. Slide the latch assembly out from the
rear.
To reinstall:
1. Slide latch assembly in from the rear.
2. Guide assembly to front using the side
access.
3. Make sure the screw holes of the
assembly line up with the screw holes in
the frame.
4. Reinsert the screws.
Note: Make sure the insulation is back in
place when finished. Failure to do so will
result in hot spots and poor baking
complaints.
5. Reattach band to the bottom of frame.
6. Reconnect wiring to the lock switches.
7. Reinstall the side panel.
8. Reinstall the rear panel.
9. Reinstall the main top.
Oven Door Hinge
The unit will have to be pulled away from the
cabinetry to remove/replace door hinges.
To Access/Replace Oven Door Hinges:
1. Disconnect the appliance from power
source before servicing.
2. Remove main top assembly as described
previously and lay aside securely.
3. Remove oven door assembly as
previously described and lay aside
securely.
4. Remove the screws securing side panel
at the top and back of frame.
5. Remove the screws securing the rear
panel to frame.
6. Slide the side panel away from the frame
at rear and lift out of the slots in the
front. Remove panel.
7. Remove two (2) screws securing hinge to
front frame flange.
8. Complete hinge assembly may be
removed.
9. Reverse procedure to reinstall.