Maytag MDE9700A Technical Information

27” Electric Dryer

⎯

Technical Information

MDE9700A *

• Due to possibility of personal injury or property damage, always contact an authorized technician for servicing or repair of this unit.

•

Refer to Service Manual 16025911 for detailed installation, operating, testing, troubleshooting, and disassembly instructions.

!

CAUTION

All safety information must be followed as provided in Service Manual 16025911.

!

WARNING

To avoid risk of electrical shock, personal injury or death; disconnect power before servicing, unless testing requires power.

Model MDE9700A*

Power Source

Voltage AC 240VAC

Motor Horsepower

Cabinet Dimensions

1/3

Height 38”

Width 27”

Depth 30.75”

Features

Cycles 16

Controls LED

Air Fluff X

Wrinkle Release

Wrinkle Prevent

X

X

Tumbler Stainless

End of Cycle Chime X

Drum Light

Freshen Up Cycle

Drying Rack

X

X

X

Weight lbs.

Uncrated 138

©2005 Maytag Services

Troubleshooting

!

WARNING

To avoid risk of electrical shock, personal injury or death; disconnect power before servicing, unless testing requires power.

Will Not Run

Will not start or run: and 5.

•

All wires are hooked up to their corresponding terminals.

• Dryer is plugged in.

• Blown fuse or circuit breaker.

• Door switch functional...door closed. Check for error code 3 (See Table for code definition).

•

Start/Pause rotary selector dial functional.

•

Control Board operational.

• Drive motor functional.

• Check motor winding resistance: 2.88ohms between pin #3 and 4, 3.5ohms between pin #4 ductwork installed.

• Poor intake air available for the dryer.

• Incorrect tumbler speed. Tumbler belt slipping.

•

Blower impeller bound; check for foreign material in blower area.

•

Customer overloading dryer.

• Check clothing labels for fabric content and cycle selected.

• Clothes too wet due to insufficient spin out by washer.

Will Not Shut Off

• Check Membrane Pad.

•

Check Electronic Control Board.

•

Short in sensor circuit.

Motor runs/ tumbler will not turn:

• Belt off or broken/damaged.

•

Idler tension spring too weak or stretched.

•

Idler pulley jammed or stuck.

Troubleshooting the electronic control circuit:

•

Check for miswiring of the electrical connector at the electronic control board.

Runs a few minutes and then stops:

•

Lint buildup around drive motor.

• Low voltage present.

• Blower impeller blocked in blower

• housing.

•

Drive motor - start switch contacts stuck closed.

Blows fuses or trips circuit breaker:

•

The amperage readings are at 240 volts. One line will be 24 amps and the other line will be 21 amps. The neutral line will be at 3 amps. If the above amperages are present, then the house wiring, fuse box or circuit breaker should be suspect.

• Shorted heating element to housing.

•

Incorrect wiring or a wire shorting to ground.

•

Drive motor winding shorting to ground.

Will Not Dry

Will not heat (motor runs):

•

Open heating element.

•

Hi-Limit trips easily or is open.

• Regulating thermostat trips easily or is open.

• Membrane switch open.

• Check Thermistor.

Improper drying/clothes wrinkled/ rough texture/long dry time:

• Lint filter is not clean.

• Restriction in exhaust.

•

Outside exhaust hood damper door stuck closed.

•

Exhaust too long, too many elbows, flex

Noisy and/Or Vibration

• Thumping Check for loose tumbler baffle, rear tumbler roller(s) worn or misaligned, out-ofround tumbler or high weld seam on tumbler.

•

Ticking Check for loose wire harness or object caught in blower wheel area.

• Scraping Check for front or rear bulkhead felt seal out of position or worn tumbler front bearings.

•

Roaring Check for blower wheel rubbing on blower housing or bad motor bearings.

• Popping or squealing sound

.

Check for a sticky or frayed belt.

Service Mode

This mode provides Service Personnel the ability to verify the operation of the dryer.

The Service Mode can be implemented at any time, including the middle of a dry cycle. While in the Service

Mode, the Technician can start special diagnostic tests such as a System Check Mode, LED Switch/Check,

Display Software version number and display diagnostic/help code listings.

Enter Service Mode:

Dryer must be on before Service Mode can be entered.

Press Chime and Temperature Keys for 3 seconds, or until 3 beeps are heard. The machine will now be in

Service Mode. Upon entry into Service Mode, the Sensor

Bar Touch Data is to be displayed.

©2005 Maytag Services

Troubleshooting

!

WARNING

To avoid risk of electrical shock, personal injury or death; disconnect power before servicing, unless testing requires power.

Exit Service Mode Key Pressed: Function Performed

Press the OFF key to exit Service Mode or repeat the Rotate the Cycle Selector

Chime and Temperature sequence. Knob to Time Dry

View current cycle temperature in

Fahrenheit.

Diagnostic Tests

The following table lists the various tests available while in the Service Mode. Before advancing to the next test, the current test running must be terminated.

Press the following keys to access:

Key Press

Wrinkle Prevent

Displays “ d ”

Then rotate the Cycle

Selector Knob

Temperature Key

Start/Pause

System Check Mode

Special

Test/Function

Display list of diagnostic codes.

To sequence thru the diagnostic and help codes.

Display software revision number

Start or pause cycle running but remain in diagnostic mode.

Display the number of cycles ago the diagnostic code occurred.

While in Service Mode, pressing the

Time and Wrinkle Prevent keys for 3 seconds, will put the dryer into the System Check mode and " in " will display. The following table lists the various functions based on the keys being pressed.

System Check Mode Table

Key Pressed:

Start/Pause rotary selector dial

Function Performed

Cycles the motor on/off.

Rotate the Cycle Selector

Knob to Delicates

Rotate the Cycle Selector

Knob to Sensor

Dry

LED’s and 7 segment display flash.

View current cycle temperature in

Celsius.

Rotate the Cycle Selector

Knob to Wrinkle Control

Segment display is “1” for sensor bar short, “0” for sensor bar open

LED/Switch Check

While in Service Mode, pressing the Chime and Wrinkle

Prevent keys for 3 seconds, will start a LED/Switch Test.

To exit the test at any point, press the same keys again for 3 seconds or press the OFF key to exit Service

Mode.

Perform the check by pressing the keys which toggle the

LED’s on and off.

All switch pads must be pressed within 5 minutes for this test to pass. PA will be displayed for five (5) seconds once all switch pads have been pressed and this test is completed. Following 10 seconds of inactivity at any point, the test will exit without any display. The

Power

Off

switch pad must be pressed twice within thirty (30) seconds to cancel this test.

Switch Action

Wrinkle Prevent Press once

Adjust Time

Time

Temperature

Dryness Level

Selector Knob

Start Pause

Press once

Press four times

Press three times

Press four times

Rotate 1 position

Press once

Diagnostic Codes

The Diagnostic Codes are identified when the severity level of the abnormality detected is higher and service may be required.

When a problem with the dryer is detected a Diagnostic

Code is assigned, and can be displayed. The Control

Board will not log multiple same codes per cycle; however, it will log as many Diagnostics as possible for the machine to continue running.

Access Diagnostic Codes by entering the Service Mode and pressing Wrinkle Prevent .

A d will be displayed.

Rotate the Cycle Selector Knob in either direction to step through the list of codes one code at a time. Once an initial direction is selected by the user (either Clockwise or Counterclockwise), subsequent movements of the knob in the same direction will show older codes. If the user changes direction and turns the knob in the

©2005 Maytag Services

Troubleshooting

!

WARNING

To avoid risk of electrical shock, personal injury or death; disconnect power before servicing, unless testing requires power. opposite direction, the more recent code will be

Code Description Trigger Action displayed.

While a diagnostic code is displayed, if the

Start/Pause button is released, the diagnostic code is again displayed .

Start/Pause button in the center of the Rotary Cycle Selector is pressed and held, the machine will display the number of cycles ago the diagnostic code occurred. When the

8 Stuck Key A key is sensed to be pressed more than

75 seconds, the key is assumed to be stuck.

Run membrane pad check and replace console w/membrane pad if necessary.

Clearing Diagnostic Codes

To clear the diagnostic code list press the

Level

1

2

3

4

and

Time

Diagnostic Codes

Dryer

Thermistor

Short Sensed

Thermistor

Open Sensed

Door Circuit

Failure

Possible motor transistor error

The

Thermistor resistance is very low.

The

Thermistor resistance is very high

Invalid state for more than 256 milliseconds

If either motor transistor is seen open or shorted during startup

Sensor Dry

keypads together for 3 seconds while viewing the list. The cycle count for each diagnostic code will be reset to 0, but not the machine cycle count.

Code Description Trigger Action

Check for:

- Clogged lint screen.

- Restricted vent system.

- Check Thermistor resistance.

Check for:

Low ambient temperature in room (Below

-22

°

F/-30

°

C).

- Outside vent damper is stuck open in wintertime.

- Loose or open wire terminals.

- Check Thermistor resistance.

Check for:

- Loose or open wire terminals in

Door Sense circuit.

Check for:

- Loose connections in motor circuit.

- Run System

Check Mode and check the motor relay function.

- If relay functions, disregard the diagnostic code.

- If relay does not function, replace machine control board.

10 No Wet Clothes Sensor bar detects no wet clothes while a

Sensor Dry

Cycle

Display Fault/Error Codes

Disp Description tS do

FE dC hE

Dryer

Thermistor

Short Sensed

Door Open

Power source frequency error

Door Circuit

Failure

Heater Error

Trigger

The Thermistor resistance is very low.

Running the dryer with door open

Invalid power source frequency

Invalid state for more than 256 milliseconds

Invalid heating temperature in running the dryer

Check for:

- Running dryer with no wet clothes in sensor dry cycle

Action Taken

Check for:

- Clogged lint screen.

- Restricted vent

system.

- Check Thermistor

resistance.

- Check for diagnostic code 1

Check for:

- Close the door, and run the dryer

- Loose or open wire terminals in

Door Sense circuit.

- Check for diagnostic code 3

Check for:

- Not using regular power source frequency

- Invalid power frequency sense circuit

Check for:

- Loose or open wire terminals in

Door Sense circuit.

- Check for diagnostic code 3

Check for:

- Restricted vent system.

- Check Thermistor resistance.

©2005 Maytag Services

Component Testing

!

WARNING

To avoid risk of electrical shock, personal injury or death; disconnect power before servicing, unless testing requires power.

Illustration Component

Thermistor Unplug harness connector and test from wire insertion side.

Pin #2 and Pin #6 of CN6

Results

10k ohms @ 77F NTC

Door Switch

Light

Belt Switch

Motor

TH1 Thermostat

85 C/185 F 25A

Unplug connectors and test switch terminals.

Door open terminals COM to NC/ 1 to 3

Door open terminals COM to NO/1 to 2

Door closed terminals COM to NC/ 1 to 3

Door closed terminals COM to NO/ 1 to 2

Unplug connectors and test switch terminals.

Check across terminals

Unplug connectors and test switch terminals.

Check across terminals switch closed

Check across terminals switch open

Unplug harness connector and test motor circuits.

Pin #4 and Pin #5 (Windings)

Pin #1 and Pin #2 (Centrifugal switch)

Unplug connectors and test Thermostat terminals.

Check across terminals

Infinity

Less than 1 ohm

Infinity

Less than 1 ohm

80 to 100 ohms

Less than 1 ohm

Infinity

2 ohms

Open

Less than 1 ohm

TH2 Hi Limit

127/99 C

261/210 F

25A

Unplug connectors and test Thermostat terminals.

Check across terminals Less than 1 ohm

TH3 Thermal Cut Off

160 C

320 F

Heater Element

Unplug connectors and test Thermostat terminals.

Check across terminals Less than 1 ohm

Sensor Bars

Unplug connectors and test Heater terminals

Unplug harness connector and test from wire insertion side.

Pin #4 to Pin # 5 of CN6

10 ohms

Infinity (Dry load)

190 ohms

±

10% (Wet load)

©2005 Maytag Services

Wiring Diagram

!

WARNING

To avoid risk of electrical shock, personal injury or death; disconnect power before servicing, unless testing requires power.

Motor Contacts

Function 1M

Start

Run

2M

= Contact closed

3M 5M 6M

Centrifugal Switch (Motor)

©2005 Maytag Services