ML-175 / ML-190 Service Manual Phase 6 / Phase 7 Microprocessor Controls American Dryer Corporation 88 Currant Road Fall River, MA 02720-4781 Telephone: (508) 678-9000 / Fax: (508) 678-9447 E-mail: techsupport@amdry.com www.amdry.com ADC Part No.
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 service this equipment. OBSERVE ALL SAFETY PRECAUTIONS displayed on the equipment or specified in the installation manual included with the dryer.
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. Table of Contents ________ Important Information ............................................. 4 Safety Precautions ............................................... 4 Routine Maintenance .............................................. 4 Cleaning ......
Important Information ________________ ! WARNING ▲ 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.
Daily Adjustments (Beginning) of each work shift. 7 Days After Installation and Every 6 Months Clean lint from the drawer/screen. Inspect lint screen and replace if torn. 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.
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. Operational Service Check Procedure Exhaust ductwork should be designed and installed by a competent technician.
Reversing Relay Panel Gas Burner Assembly 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.
Idler Shaft Assembly Tumbler Shaft Support 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 11-inch (27.94 cm) drive wheel and two pillow block bearings. 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® discs, and a rotational sensor assembly.
Main Door Switch Burner Hi-Limit (Gas Models Only) 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. 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.
Lint Drawer Servicing ______________________________ The lint drawer is located at the bottom of the dryer in the lint compartment. Simply grab the lint drawer handle, slide out the drawer, brush off the lint, and slide the drawer back in. Introduction All electrical/mechanical service or repairs should be made with the electrical power to the dryer disconnected (power off). ! WARNING ▲ Personal injury could result.
Disconnect the two “orange” wires from the high heat (225° F [107° C]) thermostat, and remove modular bracket connector, wires, and probe from bracket assembly. To Replace Keypad Label Assembly Discontinue electrical power to the dryer. Unplug keypad ribbon from rear of computer. Slowly peel off and remove keypad label assembly from control panel. Install new sensor probe assembly (ADC P/N 880251) by reversing procedure. Reestablish electrical power to the dryer.
To Test and Adjust Gas (Water Column) Pressure There are two types of devices commonly used to measure water column pressure. They are spring/mechanical-type gauges and manometers. The spring/mechanical-type gauge is not recommended, because it is easily damaged and not always accurate. A manometer is simply a glass or transparent plastic tube with a scale in inches. When filled with water and pressure applied, the water in the tube rises showing the exact water column pressure.
! WARNING ▲ To Convert from Natural Gas to L.P. Gas NOTE: All dryers are sold as natural gas, unless otherwise specified at the time the dryer order was placed. For L.P. gas the dryer must be converted as follows. Remove the four screws which secure the top cap assembly. This assembly contains the regulator adjustment screw and the terminal connections. Replace the top cap assembly with the L.P. version. To install the new L.P. orifices refer to “Replace Main Burner Orifices”.
Reverse procedure for installing new thermostat. To Adjust Sail Switch Reestablish electrical power to the dryer. With the dryer operating at a high temperature setting, pull the sail switch away from the burner. The sail switch should open and extinguish the burner. Let the sail switch damper return to the burner wall. The sail switch should close to restart the burner ignition cycle.
To Install New Main Door Glass Remove main door assembly from dryer (follow main door removal procedure). Lay main door on flat surface with front of door face up. Remove the twelve Phillips head screws securing front panel to dryer. Pull wires up through front panel door switch wire channel and gently remove front panel assembly. Reverse this procedure for installing new front panel. Remove the four #10-32 Acorn nuts. Remove glass and clean all old sealant off main door.
IMPORTANT: Tighten screws evenly and progressively. Never allow the sheave to be drawn in contact with the flange of the bushing. This gap should measure from 1/8” to 1/4”. Proper cap screw torque is 30 ft.-lb. If greater tightening forces are applied, excess pressures will be created in the hub of the mounted sheave, which may cause it to crack. To Replace Motor Pulley Discontinue electrical power to the dryer. Remove the lint drawer. Remove the lint door.
To Replace Rear Tumbler Shaft Support Wheels Disconnect electrical power to the dryer. Remove the four nuts securing the rear support box to the dryer. Remove the center Allen head bolt and Teflon® washer. Loosen the individual wheel bolts so the rear of the box can be removed. Remove the damaged wheel. Replace with new wheel. Reverse steps to replace support box. Reestablish electrical power to the dryer. Clean the shaft and slide the pillow block bearings off of the shaft.
Basket and Support V-Belt Replacement (Drive Shaft To Speed Reducing Shaft) To Replace Tumbler and Tumbler Support Discontinue electrical power to the dryer. Discontinue electrical power to the dryer. Follow procedure for removal of main door assembly. Follow procedure for removal of front panel assembly. Remove the lint drawer. Remove the lint door. Loosen two bolts securing rear pillow block bearing on the drive shaft. Remove bearing back guard.
Remove old motor pulley and bushing and place on new motor. Follow “To Replace Motor Pulley”. Reverse these steps to replace drive motor. Loosen the four bolts securing the fan shaft assembly to the base of the dryer. NOTE: Models with rear access, it may be easier to remove this plate, to remove the two rear fan shaft assembly bolts. Remove the fan assembly through front access hole. Loosen the setscrews in each bearing. Loosen the four flange bolts and two pillow block bolts.
To Replace Lint Drawer Switch No L.E.D. display on microprocessor controller (computer)... Disconnect electrical power to the dryer. Open circuit breaker switch or blown fuse. Remove lint drawer and lint door. Disconnect both 4-pin connectors at the rear of the lint switch cover. Remove the one or two screws holding the lint switch cover on. Tripped blower motor overload. Faulty wiring connection. Faulty transformer. “Emergency Stop” (E-Stop) button is depressed.
Phase 6 OPL System Diagnostics ___ Overload for impellor (fan) motor is tripping... Either an exceptionally low or high voltage supply. 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. Motor bearing failure. Motor vents are blocked with lint. Failed motor. Failed overload.
bURNER CONTROL FAIL – This routine monitors the ignition control’s gas valve output response. If the valve output signal is not present from the ignition control within the valve time limits the Phase 6 microprocessor controller (computer) determines the ignition control has failed. If this occurs when the cycle is active the machine will display “bURNER CONTROL FAIL.” If the tumbler temperature is above 100º F (38º C) the machine will continue to display “bURNER CONTROL FAIL.
L.E.D. Display Indicator Number 5 “FOR” (FORWARD) Output L.E.D. Indicator (for optional reversing model ONLY) Air Jet Circuit Indicator – OPTIONAL This indicator dot is on at the end of each cycle for approximately 60-seconds. Phase 6 OPL Microprocessor Controller (Computer) Relay Output L.E.D. Indicators There are a series of five L.E.D. indicators (ORANGE LIGHTS) located at the backside of the Phase 6 OPL microprocessor controller (computer).
If the dryer is active (running) and the lint door is opened the “LINT” L.E.D. indicator will go out and the display will read “LINT dOOR.” The dryer will stop until the lint drawer has been closed, at which time the L.E.D. display will read “PRESS START.” At this time, to resume the drying cycle press “ENTER/START” key. “MAIN” (MAIN DOOR) Input L.E.D. Indicator Should be on all the time (unless the lint door is open or the main door is opened then the “MAIN” L.E.D. indicator will go out).
Input / Output Board L.E.D. Indicators Technical Information ________________ Inputs The following section contains various technical information important to the service person in servicing and maintaining the dryer. ESTOP – (RED L.E.D.): This L.E.D. will indicate the status of the E-STOP. If the E-STOP has been pressed, then the L.E.D. is on. GAS_V – (RED L.E.D.): This L.E.D. will indicate the status of the gas valve. If the gas valve is open (ON), then the L.E.D. is on. BRHL – (RED L.E.D.): This L.E.
Data Label Correct readings should be: Natural Gas: 3.5 in wc; L.P. Gas: 10.5 in wc If water column pressure is incorrect refer to “To Adjust Gas Pressure”. Reverse procedure for removing manometer. When contacting ADC, certain information is required to ensure proper service/parts information. This information is on the data label, located on the top right corner of the dryer, viewed from the rear (refer to illustration).
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ADC Part No.
