American Dryer Corp. Phase 7 / OPL ensor Activated Fire Extinguishing System... User manual

D120 Installation Manual
Phase 7 / OPL
Sensor Activated Fire Extinguishing System
WARNING: Foryoursafetytheinformationin
thismanual mustbe followedto minimizethe
riskof fireor explosionor toprevent property
damage,personalinjury or death.
— Donot storeoruse gasolineor other flammable
vapors and liquids in the vicinity of this or any
otherappliance.
— WHATTODO IFYOUSMELLGAS:
• Donottryto lightanyappliance.
• Donottouch anyelectricalswitch;do not
useanyphoneinyourbuilding.
• Cleartheroom, buildingorareaofall
occupants.
• Immediatelycallyourgassupplierfroma
neighbor’sphone. Followthe gassupplier’s
instructions.
• Ifyoucannotreach yourgassupplier,call
thefiredepartment.
— Installationand servicemustbe performedby a
qualified installer, service agency or the gas
supplier.
AVERTISSEMENT: Assurez-vous de bien
suivrelesinstructionsdonnéesdanscettenotice
pourréduire auminimumle risqued’incendie
ou d’explosion ou pour éviter tout dommage
matériel,touteblessureou lamort.
— Ne pas entreposer ni utiliser d’essence ni
d’autres vapeurs ou liquides inflammables à
proximité de cet appareil ou de tout autre
appareil.
— QUEFAIRESIVOUSSENTEZUNEODEUR
DEGAZ:
• Nepastenter d’allumerd’appareils.
• Netouchez àaucun interrupteur. Ne pas
vousservirdes téléphonessetrouvant dans
lebâtiment.
• Évacuezlapièce,le bâtimentoulazone.
• Appelezimmédiatementvotrefournisseur
degazdepuisunvoisin. Suivez les
instructionsdufournisseur.
• Sivousnepouvezrejoindrelefournisseur
degaz,appelez leservicedes incendies.
— L’installationetl’entretiendoiventêtreassuréspar
uninstallateurou unserviced’entretienqualifié
ouparle fournisseurdegaz.
ADC Part No. 113179-3
American Dryer Corporation
88CurrantRoad
FallRiverMA02720-4781USA
Telephone: [phone] / Fax:[phone]
e-mail:[e-mail]
www.amdry.com

D120
Retain This Manual In ASafe 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 qualified technicians should service 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.
“IMPORTANTNOTETO PURCHASER”
Informationmustbeobtainedfromyourlocalgassupplierontheinstructions
tobefollowed iftheusersmells gas. Theseinstructionsmustbepostedina
prominentlocationnearthedryer.
FORYOUR SAFETY
Donot storeor usegasoline or
otherflammablevaporsand
liquidsinthevicinityofthisor
anyotherappliance.
POURVOTRESÉCURITÉ
Nepas entreposer niutiliserd’essence
nid’autresvapeursouliquides
inflammablesàproximitédecet
appareilou detoutautre appareil.
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. The illustrations included in this manual may not depict your particular dryer exactly.
Important
For your convenience, log the following information:
DATE OFPURCHASE________________________________________________________ MODELNO. __________________
RESELLER’SNAME ________________________________________________________________________________________
Serial Number(s) ________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
Replacement parts can be obtained from your reseller or the ADCfactory. When ordering replacementparts from the factory,
you can FAX your order to ADC at [phone] or telephone your order directly to the ADC Parts Department at (508)
678-9000. Pleasespecify thedryer model numberand serialnumberinaddition tothe descriptionand part number,sothat
your order is processed accurately and promptly.

IMPORTANT
YOUMUSTDISCONNECTANDLOCKOUTTHEELECTRICSUPPLYANDTHEGAS
SUPPLY OR THE STEAM SUPPLY BEFORE ANY COVERS OR GUARDS ARE
REMOVED FROM THE MACHINE TO ALLOW ACCESS FOR CLEANING,
ADJUSTING, INSTALLATION, OR TESTING OFANY EQUIPMENT PER OSHA
(OccupationalSafetyand HealthAdministration) STANDARDS.
WARNING
CHILDRENSHOULD NOTBEALLOWEDTOPLAYONORNEARTHEDRYER(S).
CHILDRENSHOULDBESUPERVISEDIFNEARDRYERSINOPERATION.
CAUTION
DRYERSSHOULDNEVERBELEFTUNATTENDEDWHILEINOPERATION.
FORYOURSAFETY
DONOTDRYMOPHEADSINTHEDRYER.
DONOTUSEDRYER INTHE PRESENCEOFDRYCLEANINGFUMES.
WARNING
UNDERNOCIRCUMSTANCES should the dryerdoorswitch, the lint drawerswitch,
or the heat safety circuit ever be disabled.
“Caution: Label all wires prior to
disconnection when servicing controls. Wiring
errors can cause improper operation.”
«Attention: Au moment de l’entretien des
commandes,étiqueteztous les filsavantde
les débrancher. Des erreurs de câblage
peuvent entraîner un fonctionnement
inadéquatetdangereux.»

WARNING
The dryer must never be operated with any of the back guards, outer tops, or service
panelsremoved. PERSONALINJURYORFIRECOULDRESULT.
IMPORTANT
PLEASEOBSERVEALLSAFETYPRECAUTIONSdisplayedontheequipmentand/or
specified in the installation manual included with the dryer.
WARNING
DRYERMUSTNEVER BE OPERATEDWITHOUTTHELINTFILTER/SCREENIN
PLACE,EVENIFANEXTERNALLINTCOLLECTIONSYSTEMISUSED.
Dryer mustnotbe installed or stored in an area where it willbe exposed to water or weather.
The wiring diagram for the dryer is located in the front electrical control box area.
IMPORTANT
Dryer must be installed in a location/environment, which the ambient temperature
remains between 40° F (4.44° C) and 130° F (54.44° C).

SECTION I
IMPORTANT INFORMATION ...............................................................................3
A. ReceivingandHandling ............................................................................................................... 3
B. SafetyPrecautions ...................................................................................................................... 4
SECTION II
SPECIFICATIONS/COMPONENT IDENTIFICATION.....................................6
A. Specifications ............................................................................................................................. 6
B. ComponentIdentification ............................................................................................................ 8
SECTION III
INSTALLATION PROCEDURES .........................................................................10
A. LocationRequirements ............................................................................................................. 10
B. Unpacking/SettingUp ............................................................................................................... 11
C. DryerEnclosureRequirements .................................................................................................. 13
D. FreshAirSupplyRequirements ................................................................................................. 14
E. ExhaustRequirements ............................................................................................................... 15
F. ElectricalInformation ................................................................................................................ 20
G. GasInformation ........................................................................................................................ 23
H. SteamInformation .................................................................................................................... 27
I. PreparationFor Operation/Start-Up ......................................................................................... 31
J. PreoperationalTests ................................................................................................................. 32
K. CompressedAirRequirements .................................................................................................. 34
L. ShutdownInstructions............................................................................................................... 35
SECTION IV
SERVICE/PARTS INFORMATION ......................................................................36
A. Service ..................................................................................................................................... 36
B. Parts ........................................................................................................................................ 36
SECTION V
WARRANTY INFORMATION...............................................................................37
A. ReturningWarrantyCards......................................................................................................... 37
B. Warranty .................................................................................................................................. 37
C. ReturningWarrantyParts .......................................................................................................... 37
Table of Contents

SECTION VI
ROUTINE MAINTENANCE ..................................................................................39
A. Cleaning ................................................................................................................................... 39
B. Adjustments ............................................................................................................................. 41
C. Lubrication ............................................................................................................................... 41
SECTION VII
MANUAL RESET BURNER HI-LIMIT INSTRUCTIONS ...............................42
A. Phase 7 .................................................................................................................................... 42
B. DualTimer ................................................................................................................................42
SECTION VIII
DATA LABEL INFORMATION .............................................................................43
A. DataLabel ............................................................................................................................... 43
SECTION IX
PROCEDURE FOR FUNCTIONAL CHECK
OF REPLACEMENT COMPONENTS ................................................................44
SECTION X
PHASE 7 OPL SYSTEM DIAGNOSTICS............................................................45
A. Diagnostic(L.E.D.Display)FaultMessages .............................................................................. 45
SECTION XI
OPTIONAL SENSOR ACTIVATED
FIRE EXTINGUISHING (S.A.F.E.) SYSTEM .....................................................47
Installation ...................................................................................................................................... 48
SensorActivatedFireExtinguishing (S.A.F.E.)SystemTheoryofOperation .................................... 51
SystemReset.................................................................................................................................. 51
OPLS.A.F.E. System Check Procedure ......................................................................................... 51

3
SECTIONI
IMPORTANTINFORMATION
A. RECEIVINGAND HANDLING
The dryer is shipped in a protective stretch wrap cover with protective cardboard corners and top cover (or
optional box) as a means of preventing damage in transit. Upon delivery, the dryer and/or packaging, and
wooden skid should be visually inspected for shipping damage. If any damage whatsoever is noticed, inspect
further before delivering carrier leaves.
Dryers damaged in shipment:
1. ALL dryers should be inspected upon receipt and before they are signed for.
2. If there is suspected damage or actual damage, the trucker’s receipt should be so noted.
3. If the dryer is damaged beyond repair, it should be refused. Those dryers, which were not damaged in a
damaged shipment, should be accepted, but the number received and the number refused must be noted
on the receipt.
4. If you determine that the dryer was damaged after the trucker has left your location, you should call the
delivering carrier’s freight terminal immediately and file a claim. The freight company considers this
concealed damage. This type of freight claim is very difficult to get paid and becomes extremely difficult
when more than a day or two passes after the freight was delivered. It is your responsibility to file freight
claims. Dryer/parts damaged in transit cannot be claimed under warranty.
5. Freight claims are the responsibility of the consignee, and ALL claims must be filed at the receiving end.
ADC assumes no responsibility for freight claims or damages.
6. If you need assistance in handling the situation, please contact the ADC Traffic Manager at (508)
678-9000.
IMPORTANT: Thedryermustbetransportedand handledinanupright positionatALLtimes.

4
B. SAFETY PRECAUTIONS
WARNING: Foryoursafety,theinformationinthismanualmustbefollowedtominimizetherisk of
fireorexplosion ortopreventproperty damage,personalinjury, orlossof life.
WARNING: Thedryermust never beoperated with anyofthe backguards,outer tops,or
servicepanelsremoved. PERSONALINJURYORFIRECOULD 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 ALLoccupants.
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 dryer, there are some articles that, due to fabric composition or
cleaning method, should not be dried in it.
WARNING: Dry only water washed fabrics. DONOTdryarticles spottedor washedin dry
cleaningsolvents,a combustibledetergent,or“allpurpose”cleaner.
EXPLOSIONCOULDRESULT.
WARNING: DONOT dry rags orarticles coatedorcontaminated withgasoline, kerosene,oil,paint,
orwax.
EXPLOSIONCOULDRESULT.
WARNING: DONOTdrymopheads. Contamination bywaxor flammablesolventswill createa
firehazard.
WARNING: DONOT useheat for dryingarticles thatcontainplastic, foam,spongerubber,or
similarlytexturedrubberlikematerials. Dryinginaheatedbasket(tumbler)maydamage
plasticsor rubberand may bea firehazard.

5
7. A program should beestablished for the inspection and cleaning of lint in the burner area, exhaust ductwork,
and area around the back of the dryer. The frequency of inspection and cleaning can best be determined
from experience at each location.
WARNING: The collectionoflintin the burnerareaandexhaust ductworkcancreatea potential fire
hazard.
8. 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, or in Canada, the Canadian Electrical
Codes Parts 1 & 2 CSA C22.1-1990 or LATEST EDITION.
NOTE: Failureto dosowillVOIDTHEWARRANTY.
9. UNDER NO CIRCUMSTANCES should the dryer door switch, the lint drawer switch, or the heat
safety circuit ever be disabled.
WARNING: PERSONALINJURYORFIRE COULDRESULT.
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 leftin thedryerafterthedrying and coolingcycleshavebeencompleted can
createa firehazard.
12. READ AND FOLLOW ALL CAUTION AND DIRECTION LABELS ATTACHED TO THE
DRYER.
13. For safety, proper operation, and optimum performance, the dryer must not be operated with a load less
than sixty-six percent (66%), 79 lbs (35.83 kg) of its rated capacity.
WARNING: YOUMUSTDISCONNECTAND LOCKOUTTHEELECTRICSUPPLYAND
THEGAS SUPPLYORTHESTEAMSUPPLYBEFOREANYCOVERSOR
GUARDSAREREMOVEDFROMTHE MACHINETOALLOWACCESS
FORCLEANING,ADJUSTING, INSTALLATION,ORTESTINGOFANY
EQUIPMENTPEROSHA(OccupationalSafetyandHealthAdministration)
STANDARDS.
IMPORTANT: Dryer mustbeinstalledinalocation/environment,whichtheambient
temperatureremains between40ºF (4.44ºC)and 130ºF (54.44ºC).

6
MAXIMUM CAPACITY (DRY WEIGHT) 120 lb 54.43 kg
TUMBLERDIAMETER 44-1/8” 112.09 cm
TUMBLER DEPTH 40-9/16” 103.02 cm
TUMBLER VOLUME 35.90 cu ft 1,016.57 L
TUMBLER/DRIVE MOTOR 1 hp 0.75 kW
BLOWER/FAN MOTOR 3 hp 2.24 kW
DOOR OPENING (DIAMETER) 31-3/8” 79.71 cm
DOOR SILL HEIGHT 26-5/8” 67.64 cm
WATER CONNECTION 3/4”-11.5 NH
(North America)
3/4” B.S.P.T. (Outside North America)
DRYERS PER 20’/40’ CONTAINER 3 / 7
DRYERS PER 48’/53’ TRUCK 9 / 10
VOLTAGE AVAILABLE 208-480v 3ø 3,4w 50/60 Hz
APPROXIMATE NET WEIGHT 1,370 lb 621.42 kg
APPROXIMATE SHIPPING WEIGHT 1,430 lb 648.64 kg
AIRFLOW 60 Hz 2,800 cfm 79.29 cmm
50 Hz 2,333 cfm 66.07 cmm
HEAT INPUT 415,000 Btu/hr 104,578 kcal/hr
EXHAUST CONNECTION (DIAMETER) 16” 40.64 cm
COMPRESSED AIR CONNECTION 1/4” Quick Connection
COMPRESSED AIR VOLUME 2.50 cfh 0.07 cmh
INLET PIPE CONNECTION 1-1/4” F.N.P.T.
1” F.B.S.P.T.
(CE and Australia Only)
VOLTAGE AVAILABLE 208-480v 3ø 3,4w 50/60 Hz
APPROXIMATE NET WEIGHT 1,370 lb 621.42 kg
APPROXIMATE SHIPPING WEIGHT 1,430 lb 648.64 kg
AIRFLOW 60 Hz 2,800 cfm 79.29 cmm
50 Hz 2,333 cfm 66.07 cmm
EXHAUST CONNECTION (DIAMETER) 16” 40.64 cm
COMPRESSED AIR CONNECTION 1/4” Quick Connection
COMPRESSED AIR VOLUME 2.50 cfh 0.07 cmh
OVEN SIZE
kW Btu/hr kcal/hr
72 245,729 61,923
VOLTAGE AVAILABLE 208-480v 3ø 3,4w 50/60 Hz
APPROXIMATE NET WEIGHT 1,450 lb 657.71 kg
APPROXIMATE SHIPPING WEIGHT 1,500 lb 680.39 kg
AIRFLOW 60 Hz 2,800 cfm 79.29 cmm
50 Hz 2,333 cfm 66.07 cmm
STEAM CONSUMPTION 450 lb/hr 204.12 kg/hr
OPERATING STEAM PRESSURE 125 psi max 8.62 bar
EXHAUST CONNECTION (DIAMETER) 16” 40.64 cm
COMPRESSED AIR CONNECTION 1/4” Quick Connection
COMPRESSED AIR VOLUME 3.25 cfh 0.09 cmh
BOILER HORSEPOWER (NORMAL LOAD) 13 Bhp
SUPPLYCONNECTION 1-1/4” F.N.P.T.
RETURN CONNECTION 1-1/4” F.N.P.T.
SECTIONII
SPECIFICATIONS/COMPONENTIDENTIFICATION
A. SPECIFICATIONS
Steam Electric Gas
Shaded areas are stated in metric equivalents 4/26/06
NOTE: ADCreserves therighttomakechanges inspecificationsatanytimewithout noticeor
obligation.

7
NOTE: ADCreserves therighttomakechanges inspecificationsatanytimewithout noticeor
obligation.
Specifications
D120

8
B. COMPONENT IDENTIFICATION
1. Dryer Front View
Illus. No. Description
1 Microprocessor Control/Keyboard (touch pad) PanelAssembly (controls)
2 Control (top access) Door Assembly
3 Main DoorAssembly
4 Lint PanelAssembly
5 Lint Door
6 Wire Diagram (located behind control door)
7 Top Console (module)Assembly

9
2. Dryer Rear View
Illus. No. Description
1 Electrical Service Connections
2 Top Console
3 Heating Unit
4 Relay/Wiring Box
5 Data Label and Installation Label
6 AirConnection
7 Exhaust Transition Piece

10
SECTIONIII
INSTALLATIONPROCEDURES
Installation should be performed by competent technicians in accordance with local and state codes. In the
absence of these codes, the installation mustconform to applicableAmerican National Standards:ANSI Z223.1-
LATEST EDITION (National Fuel Gas Code) orANSI/NFPA NO. 70-LATEST 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 (Liquid Propane [L.P.] Gas) or LATEST EDITION (for General
Installation and Gas Plumbing) or Canadian Electrical Codes Parts 1 & 2 CSAC22.1-1990 or LATESTEDITION
(for Electrical Connections).
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, 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).
1. The dryer must be installed on a sound level floor capable of supporting its weight. Carpeting must be
removed from the floor area that the dryer is to rest on.
IMPORTANT: “Thedryermustbeinstalledonnoncombustiblefloors only.”
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
Requirements in Section D).
5. Clearance provisions mustbe 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 as noted in this manual (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 this manual
(refer to Exhaust Requirements in Section E).
IMPORTANT: Dryershouldbe locatedwherea minimumamountof exhaustductwillbe necessary.
9. The dryer must be installed with a proper exhaust duct connection to the outside.

11
10. The dryer must be installed with provisions for adequate combustion and make-up air supply.
CAUTION: Thisdryer producescombustiblelint andmustbeexhausted tothe outdoors. Every6
months,inspecttheexhaustductingandremoveanylintbuildup.
IMPORTANT: Dryermustbeinstalled ina location/environment,which theambient
temperatureremains between40ºF (4.44ºC)and 130ºF (54.44ºC).
B. UNPACKING/SETTING UP
Remove protective shipping material (i.e., plastic wrap and/or optional shipping box) from dryer.
IMPORTANT: Dryermustbetransported andhandledinan uprightpositionat ALLtimes.
The dryer can be moved to its final location while still attached to the skid or with the skid removed. To unskid
the dryer, locate and remove the four (4) lag bolts securing the base of the dryer to the wooden skid. Two (2) are
at the rear base, and two (2) are located in the bottom of the lint chamber. To remove the two (2) lag bolts
located in the lint chamber area, remove the front panel.
1. Leveling Dryer
a. To level the dryer, place 4-inch (10.16 cm) square metal shims or other suitable material under the base
pads. It is suggested that the dryer be tilted slightly to the rear (refer to the illustration above).

12
2. If more headroom is needed when moving the dryer into position, the top console (module) may be removed.
a. To Remove Top Console (module)...
1) Disconnect the ground wire (A in the illustration below) located at the rear upper left corner of
the dryer.
2) Remove the six (6) sets of nuts and washers (B in the illustration below) holding the console
(module) to the base.
3) Disconnect the white plug connector (C in the illustration below) located on the top of the rear
electric service/relay box (provides power to the heat circuit).
4) Disconnect air connection from the 3-way micro valve.
5) Lift the console (module) off of the dryer base.
IMPORTANT: Thedryermustbetransportedand handledinanupright positionatALLtimes.

13
C. DRYER ENCLOSURE REQUIREMENTS
Even though a 12-inch (30.48 cm) clearance is acceptable, it is recommended that the rear of the dryer be
positioned approximately 24-inches (60.96 cm) from the nearest obstruction (i.e., wall) for ease of installation,
maintenance, and service. Bulkheads and partitions should be made from noncombustible materials. The
clearance between the bulkhead header and the dryer must be a minimum of 4-inches (10.16 cm) and must not
extend more than 4-inches (10.16 cm) to the rear of the front. A2-inch (5.08 cm) clearance is required between
the bulkhead facing and the top of the dryer.
NOTE: Bulkheadfacing shouldnotbeinstalleduntilafter thedryeris inplace. Ceilingareamustbe
locateda minimum of12-inches(30.48 cm)abovethe dryertopconsole (module) and
18-inches(45.72 cm)forsteam models.
NOTE: Whenfiresprinkler systemsarelocatedabove thedryers,aminimum of18-inches(45.72cm)
abovethedryer console(module)isrequired. Dryers maybepositionedsidewall tosidewall,
however, 1or2-inches (2.54or 5.08cm)is suggestedfor ease ofinstallation and
maintenance. Allowancesmustbemadeforthe openingandclosingof thecontroldoor and
thelintdoor.

14
D. FRESH AIR SUPPLYREQUIREMENTS
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. The dryer
must be installed with provisions for adequate combustion and make-up air supply.
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. As a general rule, an unrestricted air entrance from the
outdoors (atmosphere) of a minimum of 375 square inches (2419.35 square centimeters) is required for each
dryer. (Based on 1 square inch per 1,000 Btu.)
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 25-inches by 30-inches (63.5
cm by 76.2 cm) are 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-upairmust beprovided fromasource free ofdrycleaning solventfumes.
Make-upairthatiscontaminatedbydrycleaningsolventfumeswillresultin
irreparabledamage tothemotors andotherdryer components.
NOTE: ComponentfailureduetodrycleaningsolventfumeswillVOIDTHEWARRANTY.
A = 25-inches (63.5 cm)
B = 30-inches (76.2 cm)

15
E. EXHAUST REQUIREMENTS
1. General Exhaust Ductwork Information
Exhaust ductwork shouldbe designed and installed by a qualified professional. Improperly sized ductwork
will create excessive back pressure which results in slow drying, increased use of energy, overheating of
the dryer, and shutdown of the burner by the airflow (sail) switches, burner hi-limits, or basket (tumbler)
hi-heat thermostats. The dryer must be installed with a proper exhaust duct connection to the outside.
CAUTION: Thisdryer producescombustiblelint andmustbeexhausted totheoutdoors.
CAUTION: DRYER MUSTBE EXHAUSTEDTOTHE OUTDOORS.
CAUTION: IMPROPERLY SIZEDORINSTALLEDEXHAUSTDUCTWORKCAN
CREATEAPOTENTIALFIREHAZARD.
NOTE: Whendryersare exhaustedintoamultiple (common)exhaustline,each dryer mustbe
suppliedwith abackdraft damper.
The ductwork should be laid out in such a way that the ductwork travels as directly as possible to the
outdoors with as few turns as possible. Single or independent dryer venting is recommended.
When single dryer venting is used, the ductwork from the dryer to the outside exhaust outlet should not
exceed 20 feet (6.09 meters). In the case of multiple (common) dryer venting, the distance from the last
dryer to the outside exhaust outlet should not exceed 20 feet (6.09 meters). The shape of the ductwork
is not so critical so long as the minimum cross-sectional area is provided. It is suggested that the use of 90º
turns be avoided; use 30º and/or 45º bends/angles instead. The radius of the elbows should preferably be
1-1/2 times the diameter of the duct. Excluding basket (tumbler)/dryer elbow connections or elbows used
for outside protection from the weather, no more than two (2) elbows should be used in the exhaust duct
run. If more than two (2) elbows are used, the cross-sectional area of the ductwork must be increased in
proportion to the number of elbows used.
ALL ductwork shouldbe 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 ductwork 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 ductwork for periodic
inspection and cleaning of lint from the ductwork.
IMPORTANT: Exhaustback pressuremeasured byamanometer intheexhaust ductmustbenoless
than 0 and mustnot exceed0.3 inches (0.74 mb) of water column (W.C.).
NOTE: Whentheexhaust ductwork passesthroughawall, ceiling, orroofmadeofcombustible
materials,the opening mustbe2-inches (5.08cm)larger thantheduct (all thewayaround).
Theductmustbecenteredwithinthisopening.
IMPORTANT: Itis recommendedthatexhaust or boosterfans notbe usedin the exhaustductwork
system.

16
a. Outside Ductwork Protection
1) To protect the outside end of the horizontal ductwork from the weather, a 90° elbow bent downward
should be installed where the exhaust exits the building. If the ductwork 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: DONOT usescreens, louvers,or capson theoutside openingof theexhaust
ductwork.
2. Single DryerVenting
When possible, it is suggested to provide a separate exhaust duct for each dryer. The exhaust duct should
be laid out in such a way that the ductwork travels as directly as possible to the outdoors with as few turns
as possible. It is suggested that the use of 90° turns in the ducting be avoided; use 30° and/or 45° angles
instead. The shape of the exhaust ductwork is not critical so long as the minimum cross section area is
provided.
IMPORTANT: Theminimum duct sizefora gasunitis16-inches (40.64cm)fora roundductand
14-1/4” x 14-1/4” (36.2 cm x 36.2 cm) for a square duct and for a steam unit is
18-inches (45.72 cm) for a round duct and 16” x 16” (40.64 cm x 40.64 cm) for a
square duct. THE DUCTSIZEMUST NOT BEREDUCEDANYWHERE
DOWNSTREAMOFTHEDRYER.
IMPORTANT: Exhaustback pressuremeasuredby a manometerateach basket(tumbler)exhaust
duct area mustbeno less than 0 and must not exceed0.3 inches (0.74 mb) of water
column(W.C.).