ADC ML-175, ML-190 User Manual

ML-175 / ML-190

Service Manual

Phase 6 / Phase 7

Micropr ocessor Controls

American Dryer Corporation

88 Currant Road

Fall River, MA 02720-4781

Telephone: [phone] / Fax: [phone]

E-mail: [e-mail]

www.amdry.com

ADC Part No. 450431-3

Retain This Manual in a Safe Place for Future Reference

This product embodies advanced concepts in engineering, design, and safety. If this product is properly
maintained, it will provide many years of safe, efficient, and trouble free operation.

Only qualified technicians should ser vice this equipment.
OBSERVE ALL SAFETY PRECAUTIONS displayed on the equipment or specified in the installation

manual included with the dryer.
The following “FOR YOUR SAFETY” caution must be posted near the dryer in a prominent location.

FOR YOUR SAFETY

Do not store or use gasoline
or other flammable vapors
and liquids in the vicinity of
this or any other appliance.

We have tried to make this manual as complete as possible and hope you will find it useful. The manufacturer
reserves the right to make changes from time to time, without notice or obligation, in prices, specifications,
colors, and material, and to change or discontinue models. The illustrations included in this manual may
not depict your particular dryer exactly.

POUR VO TRE SÉCURITÉ

Ne pas entreposer ni utiliser d’essence
ni d’autres vapeurs ou liquides
inflammables à proximité de cet
appareil ou de tout autre appareil.

IMPORTANT

For your convenience, log the following information:

DA TE OF PURCHASE ________________________________________________ MODEL NO. _____________________

RESELLER’S NAME __________________________________________________________________________________

SERIAL NUMBER(S) __________________________________________________________________________________

____________________________________________________________________________________________________

____________________________________________________________________________________________________

Replacement parts can be obtained from your reseller or the ADC factory. When ordering replacement parts
from the factory , you can F AX your order to ADC at [phone] or telephone your order directly to the
ADC Parts Department at [phone]. Please specify the dryer model number and serial number in
addition to the description and part number, so that your order is processed accurately and promptly.

“IMPORTANT NOTE TO PUR CHASER”

Information must be obtained from your local gas supplier on the
instructions to be followed if the user smells gas. These
instructions must be posted in a prominent location near the dryer.

2 American Dryer Corporation 450431- 3

IMPORTANT

You must disconnect and lockout the electric
supply and the gas supply or the steam supply
before any covers or guards are removed from
the machine to allow access for cleaning,
adjusting, installation, or testing of any
equipment per OSHA standards.

Please observe all safety precautions displayed
on the equipment and/or specified in the
installation manual included with the dryer .

CAUTION

Dryer(s) should never be left unattended while
in operation.

Table of Contents ________

Important Information ............................................. 4

Safety Precautions ............................................... 4

Routine Maintenance.............................................. 4

Cleaning................................................................ 4

Adjustments ......................................................... 5

Lubrication ............................................................ 5

Installation Requirements ...................................... 5

Enclosure, Air Supply,

and Exhaust Requirements................................... 5

Electrical and Gas Requirements ......................... 6

Operational Service Check Procedure................... 6

“Caution: Label all wires prior to disconnection
when servicing controls. Wiring errors can cause
improper operation.”

«Attention: Au moment de l’entretien des
commandes, étiquetez tous les fils avant de les
débrancher. Des erreurs de câblage peuvent
entraîner un fonctionnement inadéquat et
dangereux.»

WARNING

Children should not be allowed to play on or near
the dryer(s). Children should be supervised if
near dryer(s) in operation.

Under no circumstances should the dryer door
switch(es), lint door/drawer switch(es), or heat
safety circuit(s) ever be disabled.

The dryer must never be operated with any of
the back guards, outer tops, or service panels
removed. Personal injury or fire could result.

Description of Parts ................................................. 6

Servicing.................................................................10

Troubleshooting......................................................20

Phase 6 OPL System Diagnostics .........................2 1

Diagnostic (L.E.D. Display) Failure Codes...........21

L.E.D. Display Indicators .....................................2 2

Phase 6 OPL Microprocessor Controller

(Computer) Relay Output L.E.D. Indicators..........23

Phase 7 OPL System Diagnostics .........................2 4

Diagnostic (L.E.D. Display) Failure Codes...........24

Technical Information ............................................25

The dryer must never be operated without the
lint filter/screen in place, even if an external lint
collection system is used.

FOR Y OUR SAFETY

Do not dry mop heads in the dryer. Do not
use dryer in the presence of dry cleaning
fumes.

The dryers must not be installed or stored in
an area where it will be exposed to water
and/or weather.

The wiring diagram for the dryer is located in
the front electrical control box area.

450431-3 www.amdry.com 3

List of Acronyms _____________________

DSI Direct Spark Ignition
HSI Hot Surface Ignition
in wc Inches of Water Column
L.E.D. Light Emitting Diode
L.P. Liquid Propane
OPL On-Premise Laundry (Non-Coin)
OSHA Occupational Safety and Health Administration
T.E.F.C. Totally Enclosed, Fan-Cooled

Important Information ________________

Safety Precautions

Do not store or use gasoline or other flammable vapors and
liquids in the vicinity of this or any other appliance.

Purchaser/user should consult the local gas supplier for
proper instructions to be followed in the event the user smells
gas. The instructions should be posted in a prominent
location.

Dryer must be exhausted to the outdoors.
Although ADC’s dryer is a very versatile machine, there are

some articles, that due to fabric composition or cleaning
method, should not be dried in it.

!

▲ WARNING

Dry only water-washed fabrics. Do not dry
articles spotted or washed in dry cleaning
solvents, a combustible detergent, or “all
purpose” cleaners. Fire or explosion could
result.

Do not dry rags or articles coated with gasoline,
kerosene, paint, or wax.

Do not dry mop heads. Contamination by wax or
flammable solvents will create a fire hazard.

Do not use heat for drying articles that contain
plastic, foam, sponge rubber, or similarly textured
rubberlike materials. Drying in a heated tumbler
may damage plastic or rubber and also may be a
fire hazard.

A program should be established for the inspection and
cleaning of lint in the burner area and exhaust ductwork. The
frequency of cleaning can best be determined from
experience at each location.

!

▲ WARNING

!

▲ WARNING

Articles left in the dryer after the drying and
cooling cycles have been completed can create a
fire hazard.

This dryer is not to be used in the presence of dry cleaning
solvents or fumes.

Read and follow all caution and direction labels attached to
the dryer.

!

▲ WARNING

Children should not be allowed to play on or in
the dryer(s). Children should be supervised if
near dryer(s) in operation.

Do not operate dryers with more than 125 psi (8.62 bar) steam
pressure. Excessive steam pressure can damage steam coil
and/or harm personnel.

Replace leaking flexible steam hoses or other steam fixtures
immediately . Do not operate dryer with leaking flexible hoses.
Personal injury may result.

Routine Maintenance _________________

Cleaning

A program and/or schedule should be established for periodic
inspection, cleaning, and removal of lint from various areas
of the dryer, as well as throughout the ductwork system. The
frequency of cleaning can best be determined from
experience at each location. Maximum operating efficiency
is dependent upon proper air circulation. The accumulation
of lint can restrict this airflow. If the guidelines in this section
are met, an ADC dryer will provide many years of efficient,
trouble free, and – most importantly – safe operation.

The collection of lint in the burner area and
exhaust ductwork can create a potential fire
hazard.

Lint from most fabrics is highly combustible. The

For personal safety, the dryer must be electrically grounded
in accordance with local codes and/or the National Electrical
Code ANSI/NFPA No. 70-LATEST EDITION.

NOTE: Failure to do so will void the warranty.

Under no circumstances should the dryer door or lint drawer
switch(es) or heat safety devices ever be disabled.

!

▲ WARNING

Personal injury or fire could result.

Articles should never be left unattended for an extended
period of time in the tumbler after completion of the drying
and cooling cycles.

4 American Dryer Corporation 450431- 3

accumulation of lint can create a potential fire
hazard.

Keep dryer area clear and free from combustible
materials, gasoline, and other flammable vapors
and liquids.

NOTE: Suggested time intervals shown for average usage,
which is considered six to eight operational (running) hours
per day.

Clean lint drawer/screen every third or fourth load.

NOTE: Frequency can best be determined at each
location.

!

▲ WARNING

Daily

(Beginning) of each work shift.
Clean lint from the drawer/screen. Inspect lint screen and

replace if torn.

Weekly

Clean lint accumulation from lint chamber, thermostat, and
microprocessor temperature sensor (sensor bracket) area.

!

▲ WARNING

To avoid the hazard of electrical shock,
discontinue electrical supply to dryer.

Steam Dryers

Clean steam coil fins using compressed air and a vacuum
cleaner with brush attachment.

NOTE: When cleaning steam coil fins, be careful not to
bend the fins. If fins are bent, straighten by using a fin
comb, which is available from local air-conditioning supply
houses.

Adjustments

7 Days After Installation and Every 6 Months

Inspect bolts, nuts, screws, (bearing setscrews),
nonpermanent gas connections (unions, shutoff valves,
orifices, and grounding connections). Motor and drive belts
should be examined. Cracked or seriously frayed belts should
be replaced. Tighten loose V-belts when necessary.
Complete operational check of controls and valves. Complete
operational check of all safety devices (door switch, lint drawer
switch, sail switch, burner and hi-limit thermostats).

Lubrication

The fan shaft bearings should be lubricated every three
months. Use Shell Alvania #2 or its equivalent. The motor
bearings, idler bearings and under normal/most conditions
the tumbler bearings are permanently lubricated. It is
physically possible to re-lubricate the tumbler bearings if
you choose to do so even though this practice is not
necessary. Use Shell Alvania #2 or its equivalent. The
tumbler bearings used in the dryer do not have a grease
fitting. Provisions are made in the bearing housing for the
addition of a grease fitting, which can be obtained
elsewhere, or from ADC by ordering kit P/N 882159, which
includes two fittings.

90 Days

Remove lint from tumbler, drive motors, and surrounding
areas. Remove lint from gas valve burner area with a dusting
brush or vacuum cleaner attachment.

NOTE: To prevent damage, avoid cleaning and/or touching
ignitor/flame-probe assembly.

Remove lint accumulation from inside control box and at rear
area behind control box.

6 Months

Inspect and remove lint accumulation in customer furnished
exhaust ductwork system and from dryer’s internal exhaust
ducting.

!

▲ WARNING

The accumulation of lint in the exhaust ductwork
can create a potential fire hazard.

Do not obstruct the flow of combustion and
ventilation air. Check customer furnished back
draft damper in exhaust ductwork. Inspect and
remove any lint accumulation, which can cause
damper to bind or stick.

NOTE: A back draft damper that is sticking partially closed
can result in slow drying and shut down of the heat circuit
safety switches or thermostats.

When cleaning dryer cabinet(s), avoid using harsh
abrasives. A product intended for the cleaning of
appliances is recommended.

Installation Requirements ____________

Installation should be performed by competent technicians
in accordance with local and state codes. In the absence of
these codes, the installation must conform to applicable
American National Standards: ANSI Z223.1-LATEST
EDITION (National Fuel Gas Code) or ANSI/NFPA NO. 70­LATEST EDITION (National Electrical Code) or in Canada,
the installation must conform to applicable Canadian
Standards: CAN/CGA-B149.1-M91 (Natural Gas) or CAN/
CGA-B149.2-M91 (L.P. Gas) or LATEST EDITION (for
General Installation and Gas Plumbing) or Canadian
Electrical Codes Parts 1 & 2 CSA C22.1-1990 or LATEST
EDITION (for Electrical Connections).

Enclosure, Air Supply , and Exhaust Requirements

NOTE: The following information is very brief and general.
For detailed description, refer to the “ML-175 Installation
Manual” (ADC P/N 113070).

Bulkheads and partitions around the dryer should be made
of noncombustible materials. Allowances should be made
for the opening and closing of the control door and lint drawer.
Also, allowances should be made in the rear for ease of
maintenance. (Refer to appropriate Installation Manual for
recommended distances and minimum allowances required.)

When the dryer is operating, it draws in room air, heats it,
passes this air through the tumbler, and exhausts it out of
the building. Therefore, the room air must be continually
replenished from the outdoors. If the make-up air is
inadequate, drying time and drying efficiency will be adversely
affected. Ignition problems and sail switch “fluttering”
problems on gas dryers may result, and you also could have
premature motor failure from overheating. The air supply
must be given careful consideration to ensure proper
performance of each dryer.

450431-3 www.amdry.com 5

IMPORTANT: Make-up air must be provided from a
source free of dry cleaning fumes. Make-up air that is
contaminated by dry cleaning fumes will result in
irreparable damage to motors and other dryer
components.

Exhaust ductwork should be designed and installed by a
competent technician. Improperly sized ductwork will create
excessive back pressure, which will result in slow drying,
increased use of energy , and shut down of the burner by the
airflow (sail) switch, burner hi-limit or lint chamber hi-heat
protector thermostat. (Refer to appropriate Installation
Manual for more details.)

CAUTION: Improperly sized or installed
exhaust ductwork can create a potential fire

!

hazard.

Compressed Air Requirements

The dryer requires an external supply of air (2.5 cfm @ 80
psi [0.07 cmm @ 5.52 bar) on the steam models, the air is
necessary to operate the damper system. On both steam,
as well as the gas model, the air is necessary/required for
the blower air jet operation to clean lint from the impellor/
fan (squirrel cage type).

Electrical and Gas Requirements

It is your responsibility to have all electrical connections
made by a properly licensed and competent electrician to
assure that the electrical installation is adequate and
conforms to local and state regulations or codes. In the
absence of such codes, all electrical connections, materials,
and workmanship must conform to the applicable
requirements of the National Electrical Code ANSI/NFPA NO.
70-LATEST EDITION or in Canada, the Canadian Electrical
Codes Parts 1 & 2 CSA C22.1-1990 or LATEST EDITION.

IMPORTANT: Failure to comply with these codes or
ordinances and/or the requirements stipulated in this
manual can result in personal injury or component failure.

The dryer installation must meet the American National
Standard, National Fuel Gas Code ANSI Z223.1-LATEST
EDITION, or in Canada, the Canadian Electrical Codes Parts
1 & 2 CSA C22.1-1990 or LATEST EDITION (for Electrical
Connections) as well as, local codes and ordinances, and
must be done by a qualified technician.

NOTE: Undersized gas piping will result in ignition
problems and slow drying and can create a safety hazard.

The dryer must be connected to the type of gas (natural or
L.P.) indicated on the dryer data label. If this information
does not agree with the type of gas available, contact the
reseller who sold the dryer or contact the factory.

The gas input ratings shown on the dryer data label are for
elevations up to 2,000 feet (610 meters), unless elevation
requirements of over 2,000 feet (610 meters) were specified
at the time the dryer order was placed with the factory. The
adjustment for dryers in the field for elevations over 2,000
feet (610 meters) are made by changing the burner orifices.
If this adjustment is necessary, contact the reseller who
sold the dryer or contact the factory.

Operational Service Check Procedure

Turn on electric power to the dryer.
To start dryer:
Display will read “READY.”
Press “E” on the keypad of microprocessor controller

(computer).
The dryer will start to run.

NOTE: Pressing keypad “A,” “B,” “C,” “D,” or “F” will also
start the dryer. Six preprogrammed drying cycles (“A”
through “F”) have been stored in the computer’s memory.
(Refer to Computer Operator’s Manual for details.)

Make a complete operational check of all the operating
controls to assure that the timing is correct, temperature
selection switches are functioning, etc.

Make a complete operational check of all safety-related
circuits: door switch(es), hi-limit thermostat, sail switch,
cycling thermostats, etc.

For gas dryers, a gas pressure test should be taken at the
gas valve pressure tap of each dryer to assure that the water
column pressure is correct and consistent.

NOTE: Water column pressure requirements (measured
at the pressure tap on the gas valve body):

Natural Gas – 3.5 in wc; L.P. Gas – 10.5 in wc

If computer program changes are required, refer to the
Phase 6 OPL Operator’s Manual (ADC P/N 113022) for
details.

The dryer should be operated through one complete cycle
to assure that no further adjustments are necessary and
that all components are functioning properly.

Check the electric service phase sequence. While the dryer
is operating, check to see if the tumbler is rotating in the
proper direction. Looking from the front, the tumbler should
spin in the clockwise direction. If so, the phasing is correct.
If the phasing is incorrect, reverse two leads at connections
L1, L2, or L3 of power supply to the dryer.

Description of Parts __________________

Control Panel (Microprocessor)

Opening the control panel will allow access to the major
components, which include the computer board and keypad.
The keypad inputs to the computer what temperature and
program has been selected. The computer controls the
entire operation of the machine. It accepts inputs and gives
outputs to various parts throughout the machine.

NOTE: Any burner changes must be made by a qualified
technician.

6 American Dryer Corporation 450431- 3

Reversing Relay Panel

Lifting the control door will reveal the reversing relay box.
Located on the back of the relay box is the reversing relay
panel. Included on this panel is a 4-position terminal block,
blower overload, blower contactor, reversing contactor, 24
VAC transformer, fuse or circuit breaker, ground lug, and
possibly an arc suppressor board.

Steam Coil and Damper System

The steam coil is constantly charged, thereby eliminating
repeated expansion and contraction and also provide instant
heating to start the drying process. The steam damper,
located on top of the steam coil, is the only temperature
controlling device in this system. When the steam damper
is open, ambient air is drawn through the coil providing
heat to the dryer. When the steam damper is closed, ambient
air is drawn directly into the tumbler, bypassing the coil,
allowing a rapid cool down.

Gas Burner Assembly

Gas heated dryers are equipped with a gas burner assembly
consisting of four burner tubes, gas valve, ignitor, flame­probe, sail switch, and hi-limit thermostat. The inlet piping
enters through the rear of the dryer on the left-hand side
(viewing from the front) and runs to the front of the dryer
where the gas valve is located.

Drive Motor

The T.E.F.C. drive motor is located in the right front hand
corner of the dryer. It sits on an adjustable base so that the
motor can be easily adjusted to the left or right.

Blower Motor and Impellor (Gas and Steam)

The impellor is shaft driven. The blower motor drives the
shaft on which the impellor is mounted.

NOTE: With the dryer off or no air supply to the damper
piston, the damper is in the cool down mode.

Steam Coil pH Level

NOTE: The normal pH level for copper type steam coils
must be maintained between a value of 8.5 to 9.5. For
steel type steam coils the pH level must be maintained
between a value of 9.5 to 10.5. These limits are set to
limit the acid attack of the steam coils.

IMPORTANT: Coil failure due to improper pH level will
void the warranty.

450431-3 www.amdry.com 7

Idler Shaft Assembly

The idler shaft is located on the left side of the machine and
is just above the blower motor. The idler shaft assembly
consists of one 1 1-inch (27.94 cm) drive wheel and two pillow
block bearings.

Speed Reducing Shaft

The speed reducing shaft is located on the right side and is
above the drive motor. The idler assembly consists of two
idler pulleys. The idler’s main purpose is to reduce the
speed and increase torque provided to the tumbler.

Tumbler Shaft Support

The tumbler shaft support is located in the rear,
approximately at the center of the dryer. The arrangement
consists of a tumbler shaft support bracket, two high impact
wheels, tumbler adjustment plate, Teflon
rotational sensor assembly.

®

discs, and a

Rotational Sensor Assembly

The rotational sensor assembly is located in the rear of the
dryer. It consists of a magnet and rotational sensor switch,
which is mounted to the bearing cap. The magnet is
screwed to the shaft.

The magnetic rotational sensor switch senses the rotation of
the tumbler.

Drive Shaft

The drive shaft is located on the right side and is above the
drive motor. The drive shaft consists of one 11-inch (27.94
cm) drive wheel, one pulley, and two pillow block bearings.
The purpose of the drive shaft is to drive the tumbler.

Tumbler

The tumbler consists of four ribs and four perforated panels,
along with a front and back, which are welded together as an
assembly. The tumbler also consists of a trunnion, which
supports the tumbler in the rear.

8 American Dryer Corporation 450431- 3

Main Door Switch

The main door switch is located near the main door hinge.
When the main door opens, the switch will also open,
preventing the dryer from operating. The main door switch
is a safety device and should never be disabled.

Burner Hi-Limit (Gas Models Only)

A burner hi-limit thermostat is located on the burner. This is
a manual reset disc-type thermostat set at 330° F (165° C).
If the flame in the burner should get too hot, this thermostat
will shut off the burner. This is generally caused by low
airflow through the dryer.

Sail Switch (Gas Models Only)

The sail switch is located on the front of the burner box. A
sail switch consists of a round damper plate on a lever arm,
which is in contact with an electric switch. When the fan/
blower comes on, it draws air through the burner box. This
creates a negative pressure inside the burner box, and this
negative pressure pulls in the round damper and activates
the sail switch.

Tumbler Hi-Limit

This is located in the lint compartment above the lint drawer .
This bracket consists of two devices. One is a temperature
sensor probe and the other is a hi-limit thermostat, which is
set at 225° F (107° C).

450431-3 www.amdry.com 9