American Dryer Corp. Gas/Electric/Steam AD-75HS User manual

AD-75HS
Installation Manual
081398GS/abe ADC Part No. 113039
For replacement parts, contact the distributor from which the dryer
was purchased or
American Dryer Corporation
88 Currant Road
Fall River MA 02720-4781
Telephone: [phone] / Fax: [phone]
E-mail: [e-mail]
(Gas/Electric/Steam)
WARNING: For your safety the information in this manual must be
followed to minimize the risk of fire or explosion or to
prevent property damage, personal injury or death.
Do not store or use gasoline or other flammable vapor
and liquids in the vicinity of this or any other
appliance.
WHAT DO YOU DO IF YOU SMELL GAS
* Do not try to light any appliance.
* Do not touch any electrical switch; do not use any phone in your
building.
* Clear the room, building or area of all occupants.
* Immediately call your gas supplier from a neighbor's phone.
Follow the gas supplier's instructions.
* If you cannot reach your gas supplier, call the fire department.
Installation and service must be performed by a qualified installer,
service agency or the gas supplier.

Retain This Manual In A Safe Place For Future Reference
American Dryer Corporation products embody 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 properly licensed technicians should service this equipment.
OBSERVE ALL SAFETY PRECAUTIONS displayed on the equipment or specified in the installation/operator's
manual included with the dryer.
WARNING: UNDER NO CIRCUMSTANCES should the door switch or the heat circuit devices
ever be disabled.
WARNING: The dryer must never be operated with any of the back guards, outer tops, or
service panels removed. PERSONAL INJURY or FIRE COULD RESULT.
We have tried to make this manual as complete as possible and hope you will find it useful. ADC 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.
Important
For your convenience, log the following information:
Replacement parts can be obtained from your distributor or the ADC factory. When ordering replacement parts
from the factory, you can FAX your order to ADC at [phone] or telephone your orders 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.
The illustrations on the following pages may not depict your particular dryer exactly. The illustrations are a
composite of the various dryer models. Be sure to check the descriptions of the parts thoroughly before ordering.
DATE OF PURCHASE MODEL NO.
DISTRIBUTORS NAME
Serial Number(s)
AD-75
IMPORTANT NOTE TO PURCHASER
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.

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 (Occupational Safety and Health
Administration) STANDARDS.
CAUTION
LABEL ALL WIRES PRIOR TO DISCONNECTION WHEN SERVICING
CONTROLS. WIRING ERRORS CAN CAUSE IMPROPER AND DANGER-
OUS OPERATION.
DRYER(S) SHOULD NEVER BE LEFT UNATTENDED WHILE IN
OPERATION.
CAUTION
VERIFY PROPER OPERATION AFTER SERVICING.
WARNING
The dryer must never be operated with any of the back guards, outer tops,
or service panels removed. PERSONAL INJURY or FIRE COULD
RESULT.

DO NOT STORE OR USE GASOLINE OR OTHER FLAMMABLE
VAPOR AND LIQUIDS IN THE VICINITY OF THIS OR ANY OTHER
APPLIANCE.
FOR YOUR SAFETY
DO NOT DRY MOP HEADS IN THE DRYER.
DO NOT USE DRYER IN THE PRESENCE OF DRY CLEANING FUMES.
IMPORTANT
PLEASE OBSERVE ALL SAFETY PRECAUTIONS displayed on the
equipment and/or specified in the installation/operator's manual included with
the dryer.
Dryer(s) must not be installed or stored in an area where it will be exposed to
water and/or weather.

Table of Contents
SECTION I
IMPORTANT INFORMATION ............................................................................... 3
A. Receiving and Handling............................................................................................................ 3
B. Safety Precautions ..................................................................................................................... 4
SECTION II
SPECIFICATIONS .................................................................................................... 6
A. Specifications ............................................................................................................................ 6
B. Component Identification .......................................................................................................... 8
SECTION III
INSTALLATION REQUIREMENTS ................................................................... 10
A. Location Requirements ........................................................................................................... 10
B. Unpacking/Setting Up ............................................................................................................. 11
C. Dryer Enclosure Requirements................................................................................................12
D. Fresh Air Supply ..................................................................................................................... 13
E. Exhaust Requirements ............................................................................................................ 14
F. Electrical Information .............................................................................................................. 18
G. Gas Information ...................................................................................................................... 26
H. Steam Information ................................................................................................................... 30
I. Preparation For Operation/Start-up ......................................................................................... 35
J. Preoperational Tests ................................................................................................................. 36
K. Preoperational Instructions ...................................................................................................... 38
L. Shut Down Instructions ........................................................................................................... 39
SECTION IV
SERVICE/PARTS INFORMATION ..................................................................... 40
A. Service .................................................................................................................................... 40
B. Parts ......................................................................................................................................... 40
SECTION V
WARRANTY INFORMATION ............................................................................. 41
A. Returning Warranty Card(s) .................................................................................................... 41
B. Parts ......................................................................................................................................... 41
C. Returning Warranty Card(s) .................................................................................................... 41

SECTION VI
ROUTINE MAINTENANCE ................................................................................. 43
A. Cleaning .................................................................................................................................. 43
B. Adjustments ............................................................................................................................. 45
SECTION VII
PROCEDURE FOR FUNCTIONAL CHECK OF REPLACEMENT
COMPONENTS ....................................................................................................... 46
SECTION VIII
REVERSING TIMER SPIN/DWELL ADJUSTMENTS ...................................49
SECTION IX
TECHNICAL INFORMATION .............................................................................50
Data Label..................................................................................................................................... 51
SECTION X
TROUBLESHOOTING............................................................................................52
Microprocessor (Computer) Models.............................................................................................. 54
Dual Timer Models ....................................................................................................................... 64

3
SECTION I
IMPORTANT INFORMATION
A. RECEIVING and HANDLING
Thedryerisshipped inaprotective stretchwrapcover withprotective cardboard cornersand topcover(or
optionalbox)asa means ofpreventing damage intransit. Upondelivery, thedryerand/or packaging,and
woodenskidshouldbevisuallyinspectedforshippingdamage. Ifanydamagewhatsoeverisnoticed,inspect
furtherbeforedeliveringcarrierleaves.
Dryersdamagedinshipment.
1. ALLdryersshouldbeinspecteduponreceiptandbeforetheyaresignedfor.
2. Ifthereissuspecteddamageoractualdamage,thetrucker'sreceiptshouldbesonoted.
3. Ifthedryerisdamagedbeyondrepair,it shouldberefused. Thosedryerswhichwerenot damaged ina
damagedshipmentshouldbeaccepted,butthenumberreceivedandthenumberrefusedmustbenoted
onthereceipt.
4. Ifyoudeterminethatthedryer was damagedafterthe truckerhasleftyour location,youshould call the
deliveringcarrier's freightterminal immediatelyand filea claim. Thefreightcompany considersthis
concealeddamage. Thistypeoffreightclaimisverydifficult to get paid and becomes extremely difficult
whenmorethan adayortwopassesafterthefreightwasdelivered. Itisyourresponsibilitytofilefreight
claims. Dryer/partsdamagedintransitcannotbeclaimedunderwarranty.
5. Freightclaimsaretheresponsibilityoftheconsignee,and ALLclaimsmustbefiledatthereceivingend.
ADCassumesnoresponsibilityforfreightclaimsordamages.
6. Ifyouneedassistanceinhandlingthesituation,pleasecontacttheADCTrafficManagerat(508)678-9000.
IMPORTANT: Thetumblersectionofthedryermustbetransportedandhandledinanupright
positionatalltimes.

4
B. SAFETY PRECAUTIONS
WARNING: For your safety, the information in this manual must be followed to minimize the
risk of fire or explosion or to prevent property damage, personal injury, or loss of
life.
WARNING: The dryer must never be operated with any of the back guards, outer tops, or
service panels removed. PERSONAL INJURY or FIRE COULD RESULT.
1. DO NOT store or use gasoline or other flammable vapors and liquids in the vicinity of this or any other
appliance.
2. 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.
3. WHAT TO DO IF YOU SMELL GAS..
a. DO NOT try to light any appliance.
b. DO NOT touch any electrical switch.
c. DO NOT use any phone in your building.
d. Clear the room, building, or area of ALL occupants.
e. Immediately call your gas supplier from a neighbor's phone. Follow the gas supplier's instructions.
f. If you cannot reach your gas supplier, call the fire department.
4. Installation and service must be performed by a qualified installer, service agency, or gas supplier.
5. Dryer(s) must be exhausted to the outdoors.
6. Although ADC produces 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" cleaner.
EXPLOSION COULD RESULT.
WARNING:DO NOT dry rags or articles coated or contaminated with gasoline, kerosene, oil,
paint, wax.
EXPLOSION COULD RESULT.
WARNING:DO NOT dry mop heads. Contamination by wax or flammable solvents will create
a fire hazard.
WARNING:DO NOT use heat for drying articles that contain plastic, foam, sponge rubber, or
similarly textured rubber materials. Drying in a heated basket (tumbler) may
damage plastics or rubber and also may be a fire hazard.

5
7. A program should be established for the inspection and cleaning of lint in the heating unit area, exhaust
duct work, and inside the dryer. The frequency of inspection and cleaning can best be determined from
experience at each location.
WARNING: The collection of lint in the burner area and exhaust duct work can create a
potential fire hazard.
8. For personal safety, the dryer must be electrically grounded in accordance with local codes and/or the
National Electric Code ANSI/NFPA NO. 70-LATEST EDITION.
NOTE: Failure to do so will VOID THE WARRANTY.
9. UNDER NO CIRCUMSTANCES should the dryer door switches or heat safety circuit ever be disabled.
WARNING: PERSONAL INJURY or FIRE COULD RESULT.
10. This dryer is not to be used in the presence of dry cleaning solvents or fumes.
11. Remove articles from the dryer as soon as the drying cycle has been completed.
WARNING: Articles left in the dryer after the drying and cooling cycles have been completed
can create a fire hazard.
12. DO NOT operate steam dryers with more than 125 PSI steam pressure. Excessive steam pressure can
damage steam coil and/or harm personnel.
13. Replace leaking flexible hoses or other steam fixtures immediately. DO NOT operate the dryer with
leaking flexible hoses. PERSONAL INJURY MAY RESULT.
14. 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.
15. READ and FOLLOW ALL CAUTION and DIRECTION LABELS ATTACHED TO THE DRYER.
WARNING: YOU MUST DISCONNECT and LOCKOUT THE ELECTRIC SUPPLY and
THE GAS 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 (Occupational Safety and Health Administration) STANDARDS.

6
SECTION II
SPECIFICATIONS/COMPONENT IDENTIFICATION
A. SPECIFICATIONS
Gas
Electric
Steam
* For non-reversing models.
** A minimum of 3/4" pipe must be supplied to the gas inlet for each dryer.
IMPORTANT: Steam dryers must be provided with clean, dry, regulated 80 PSI (+/- 10 psi) air supply.
NOTE:ADC reserves the right to make changes in specifications at any time, without notice or
obligation.
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7
Specifications
ADG-75HS
ADE-75
ADS-75
NOTE:ADC reserves the right to make changes in specifications at any time, without notice or
obligation.

8
B. COMPONENT IDENTIFICATION
1. Dryer Front View
Illus. No. Description
1 Controls
2 Control (top access) Door Assembly
3 Main Door Assembly
4 Lint Compartment Area (lint screen located behind door)
5 Data Label and Installation Label (located behind control [service] door)

9
2. DryerRearView
NOTE: 1/8-inch Compressed Air Supply Inlet (for Steam Models Only) is located behind the
Electric Service Relay Box.
Illus. No. Description
1 Heating Unit
2 1/8" Compressed Air Supply Inlet
(behind Electric Service Relay Box for steam units Only)
3* Electric Service Relay Box
4 Tumbler Bearing Mount Assembly
5 Idler Bearing Mount Assembly
6 Blower Motor Assembly
7 Leveling Leg (rear)
8 Basket (Drive) Motor Assembly (Reversing Models Only)
9 Dryer Exhaust
* Electric service connections for Gas Models and Steam Models are made in this box.

10
SECTION III
INSTALLATION PROCEDURES
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: National
Fuel Gas Code ANSI.Z223.1-LATEST EDITION and/or National Electric Code ANSI/NFPA NO. 70-LATEST
EDITION.
A. LOCATION REQUIREMENTS
Before installing the dryer, be sure the location conforms to local codes and ordinances. In the absence of such
codes or ordinances the location must conform with the National Fuel Gas Code ANSI.Z223.1-LATEST
EDITION.
1. The dryer must be installed on a sound level floor capable of supporting its weight. It is recommended that
carpeting be removed from the floor area that the dryer is to rest on.
2. The dryer must not be installed or stored in an area where it will be exposed to water and/or weather.
3. The dryer is for use in noncombustible locations.
4. Provisions for adequate air supply must be provided as noted in this manual (refer to Fresh Air Supply in
Section D).
5. Clearance provisions must be made from combustible construction as noted in this manual (refer to Dryer
Enclosure Requirements in Section C).
6. Provisions must be made for adequate clearances for servicing and for operation as noted in this manual
(refer to Dryer Enclosure Requirements in Section C).
7. Dryer must be exhausted to the outdoors (refer to Exhaust Requirements in Section E).
8. Dryer must be located in an area where correct exhaust venting can be achieved as noted in the manual
(refer to Exhaust Requirements in Section E).
IMPORTANT: Dryer should be located where a minimum amount of exhaust duct will be
necessary.

11
B. UNPACKING/SETTING UP
Remove protective shipping material (i.e., plastic wrap, and/or optional shipping box) from dryer.
IMPORTANT: Dryer must be transported and handled in an upright position at all times.
The dryer can be moved to its final location while still attached to the skid or with the skid removed. To un-skid
the dryer, locate and remove the four (4) bolts securing the base of the dryer to the wooden skid. Two (2) are at
the rear base (remove the back panel for access), and two (2) are located in the bottom of the lint chamber. To
remove the two (2) bolts located in the lint chamber area, remove the lint door.
With the skid removed, to make it easier to slide the dryer into its final position, slightly lower ALL four (4)
leveling legs, so that the dryer will slide on the legs instead of the base frame.
To increase bearing life and improve efficiency, the dryer should be tilted slightly to the rear.
The lint coops of ALL AD-75 dryers are supported during shipping by a bracket. REMOVE THIS BRACKET
BEFORE STARTING THE DRYER.
1. Leveling Dryer
The dryer is equipped with four (4) leveling legs, one at each corner of the base. Two (2) are located at the
rear of the dryer base, and two (2) are located in the lint chamber (coop). To increase bearing life and
improve efficiency, the dryer should be tilted slightly to the rear.

12
C. DRYER ENCLOSURE REQUIREMENTS
Bulkheads and partitions should be made of noncombustible materials and must be located a minimum of
12-inches (18-inches or more is recommended for ease of installation, maintenance , and service) above the
dryer outer top, except along the front of the dryer which may be partially closed in if desired. The clearance
between the bulkhead header and the dryer must be a minimum of four (4) inches and must not extend more
than four (4) inches to the rear of the front. The bulkhead facing must not be closed in all the way to the top of
the dryer. A one (1) inch clearance is required.
NOTE: Allowances must be made for opening the control door.
Dryers may be positioned side wall to side wall. However, a 1/16" minimum allowance must be made for
opening and closing of the control door and the lint door. It is suggested that the dryer be positioned about two
(2) feet away from the nearest obstruction for ease of installation, maintenance, and service (to be measured
from the back guard.) (Refer to the illustration above for details.)
NOTE: Air considerations are important for proper and efficient operation.
IMPORTANT: Even though a minimum of only 12-inches is required, 18-inches or more is
suggested. The additional clearance is advantageous for ease of installation and
service.
IMPORTANT: When fire sprinkler systems are located above the dryers, a minimum of
18-inches above the dryer console (module) is required. Dryers may be
positioned side wall to side wall however, a 1/16-inch minimum allowance is
required between dryers (or wall) for ease of installation and maintenance.
Allowances must be made for the opening and closings of the control door and
the lint door.

13
D. FRESH AIR SUPPLY
When the dryer is operating, it draws in room air, heats it, passes this air through the basket (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 may result, as well as premature motor failure from overheating.
Air supply (make-up air) must be given careful consideration to assure proper performance of each dryer. An
unrestricted source of air is necessary for each dryer. An air flow of 1,200 cfm (cubic feet per minute) must be
supplied to each gas and electric dryer and 1,350 cfm (cubic feet per minute) must be supplied to each steam
dryer. As a general rule, an unrestricted air entrance from the outdoors (atmosphere) of a minimum of 1-1/2
square feet is required for each dryer.
To compensate for the use of registers or louvers used over the openings, this make-up air must be increased by
approximately thirty-three percent (33%). Make-up air openings should not be located in an area directly near
where exhaust vents exit the building.
It is not necessary to have a separate make-up air opening for each dryer. Common make-up air openings are
acceptable. However, they must be set up in such a manner that the make-up air is distributed equally to ALL
the dryers.
EXAMPLE: For a bank of four (4) dryers, two (2) unrestricted openings measuring 2 feet by 1-1/2 feet
(6 square feet) is acceptable.
Allowances must be made for remote or constricting passageways or where dryers are located at excessive
altitudes or predominantly low pressure areas.
IMPORTANT: Make-up air must be provided from a source free of dry cleaning solvent fumes.
Make-up air that is contaminated by dry cleaning solvent fumes will result in
irreparable damage to motors and other dryer components.
NOTE: Component failure due to dry cleaning solvent fumes will VOID THE WARRANTY.

14
E. EXHAUST REQUIREMENTS
1. GeneralExhaustDuctWorkInformation
Exhaustductworkshouldbedesignedandinstalled by a qualifiedprofessional. Improperlysizedduct
workwillcreateexcessivebackpressurewhichresultsinslowdrying,increaseduseofenergy,overheating
ofthedryer,andshutdownoftheburnerbytheairflow(sail)switches,burnerhi-limits,orbasket(tumbler)
hi-heatthermostats.
CAUTION: DRYER MUSTBEEXHAUSTEDTO THE OUTDOORS.
CAUTION: IMPROPERLYSIZEDORINSTALLEDEXHAUST DUCT WORK CAN
CREATEAPOTENTIAL FIRE HAZARD.
Theduct work shouldbe laidoutin sucha waythattheduct worktravelsasdirectly aspossibleto the
outdoorswithasfewturnsaspossible. Singleorindependentdryerventingisrecommended.
HORIZONTAL VENTING:
Whensingledryerventingisused,thelengthofductwork,fromthedryertotheoutsideexhaustoutlet,should
notexceedfifteen(15)feet.Theminimumdiameterofthisduct workmustbeatleast10-inches(eventhough
thedryer exhaustduct forgas andelectricunits isonly 8-inches).In thecaseof multiple(common) dryer
venting,thedistancefromthelastdryerto theoutsideexhaustoutlet shouldnotexceedfifteen(15)feet.The
shapeoftheductworkisnotcriticalsolongastheminimumcross-sectionalareais provided. It is suggested
that the use of 90° turns be avoided; use 30° and/or 45° angles instead. The radius of the elbows should
preferablybe1-1/2timesthediameterof theduct. Includingbasket(tumbler)/dryerelbowconnections or
elbowsusedforoutsideprotectionfromtheweather,nomorethantwo(2)elbowsshouldbeusedintheexhaust
ductrun. Ifmorethan two(2)elbows areused,the crosssectionalarea of theductwork mustbeincreased.
ALLduct workshouldbesmoothinsidewith noprojections from sheetmetal screwsorother obstructions
whichwillcollect lint. When addingducts, theduct to beadded shouldoverlap theduct to whichit isto be
connected. ALLductworkjointsmustbetapedtopreventmoistureandlintfromescapingintothebuilding.
Inspectiondoorsshouldbeinstalledatstrategic pointsintheexhaustductwork forperiodicinspectionand
clean-outoflintfromtheductwork.
VERTICAL VENTING:
Whensingledryerventingisusedthelengthoftheductworkfromthedryertotheoutsideexhaustoutletshould
notexceedtwenty(20)feet.Theminimumdiameterofthisductworkmustbeatleast12-inches(eventhough
thedryer exhaustduct forgas andelectric unitsis only8-inches) Inthe caseof multiple(common) dryer
venting,thedistancefromthelastdryertotheoutsideexhaustoutletshouldnotexceedtwenty(20)feet.The
shapeoftheductworkisnotsocriticalsolongastheminimumcrosssectionalareaisprovided.Itissuggested
that the use of 90º turns be avoided; use 30ºand/or 45ºbends instead.. The radius of the elbows should
preferably be 1-1/2 times the diameter of the duct. ALL duct work should be smooth inside with no
projectionsfromsheetmetalscrewsorotherobstructionswhichwillcollectlint. Whenaddingducts,theduct
tobe addedshould overlaptheduct towhich itisto beconnected. ALLduct workjointsmustbetapedto
preventmoistureandlintfrom escapingintothe building. Inspection doorsshouldbeinstalled at strategic
pointsintheexhaustductworkforperiodicinspectionandclean-outoflintfromtheductwork.
IMPORTANT: Exhaustbackpressuremeasuredbyamanometerintheexhaustduct shouldnot
exceed0.3-inchesofwatercolumn.
IMPORTANT: Minimumductworkdiameterforhorizontalventingis10-inchesandfor
verticalventingtheminimumis12-inches.

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NOTE: Wheretheexhaustductworkpassesthroughawall,ceiling,orroofmadeofcombustible
materials,theopeningmustbe2-incheslarger(allthewayaround)thantheduct. The
ductmustbecenteredwithinthisopening.
a. OutsideDuctWorkProtection
1) Toprotecttheoutsideendofhorizontalductworkfromtheweather,a90° elbow bentdownward
shouldbe installedwhere the exhaust exitsthe building. Iftheduct worktravelsvertically up
throughtheroof,itshouldbeprotectedfromtheweatherbyusinga180°turntopointtheopening
downward. Ineithercase,allowatleasttwicethediameteroftheductbetweentheductopeningand
thenearestobstruction.
IMPORTANT:DONOTusescreensorcapsontheoutsideofopeningofexhaustductwork.
2. SingleDryerVenting
Wherepossible,itissuggestedtoprovideaseparateexhaustductforeachdryer. Theexhaustductshould
belaidoutinsuchawaythattheductworktravelsasdirectlyaspossibletotheoutdoorswithasfewturns
aspossible. Itissuggestedthattheuseof90°turns in theductingbeavoided;use30°and/or 45° angles
instead. Theshapeofthe exhaustduct work isnot criticalsolong asthe minimum crosssection areais
provided.
IMPORTANT: Minimumductsizeforadryerthatisventedhorizontallyis10-inchesfora
roundductoranequivalentof80squareinches. THEDUCTSIZEMUST
NOTBEREDUCEDANYWHEREDOWNSTREAM OF THE DRYER.
IMPORTANT: Exhaustbackpressuremeasuredbyamanometerateachbasket(tumbler)
exhaustductareashouldnotexceed0.3-inchesofwatercolumn.
IMPORTANT: Minimumductsizeforadryerthatisventedverticallyis12-inchesforaround
ductor anequivalentof120squareinches. THEDUCTSIZEMUSTNOT
BEREDUCEDANYWHEREDOWNSTREAMOFTHEDRYER.

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IMPORTANT: For extended duct work runs, the cross section area of the duct work can only be
increased to an extent. When the duct work approaches the maximum limits
noted in this manual, a professional heating venting air conditioning (HVAC)
firm should be consulted for proper venting information.
ALL duct work should be smooth inside with no projections from sheet metal screws or other obstructions
which will collect lint. When adding ducts, the duct to be added should overlap the duct to which it is to be
connected. ALL duct work joints must be taped to prevent moisture and lint from escaping into the
building. Inspection doors should be installed at strategic points in the exhaust duct work for periodic
inspection and clean-out of lint from the duct work.
NOTE: Where the exhaust duct passes through a wall, ceiling, or roof made of combustible
materials, the opening must be 2-inches larger (all the way around) than the duct. The
duct must be centered within this opening.
a. Outside Duct Work Protection
1) To protect the outside end of horizontal duct work from the weather, a 90° elbow bent downward
should be installed where the exhaust exits the building. If the duct work travels vertically up
through the roof, it should be protected from the weather by using a 180° turn to point the opening
downward. In either case, allow at least twice the diameter of the duct between the duct opening and
the nearest obstruction.
IMPORTANT:DO NOT use screens or caps on the outside of opening of exhaust duct work.