JLA D-78 User manual

D-78
(Gas/HSI/DSI/Phase 7 with S.A.F.E.)
Installation Manual
032502JEV/rmoles ADCPartNo.113373
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 lightany appliance.
• Donottouch anyelectrical switch;donot
useanyphoneinyourbuilding.
• Cleartheroom, buildingor areaof all
occupants.
• Immediatelycallyourgassupplierfroma
neighbor’sphone. Followthe gas supplier’s
instructions.
• Ifyoucannotreach yourgas supplier,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. Nepas
vousservirdes téléphonessetrouvant dans
lebâtiment.
• Évacuezlapièce,le bâtimentou lazone.
• Appelezimmédiatementvotrefournisseur
degazdepuisunvoisin. Suivez les
instructionsdufournisseur.
• Sivousnepouvezrejoindrelefournisseur
degaz,appelez leservicedes incendies.
— L’installationetl’entretiendoiventêtreassuréspar
uninstallateurou unservice d’entretienqualifié
ouparle fournisseurdegaz.
JLALimited
Meadowcroft Lane, Halifax Road
Ripponden
WestYorkshire, England
HX64AJ
Telephone:[phone]/Fax:[phone]

“IMPORTANTNOTETOPURCHASER”
Informationmustbeobtainedfromyourlocalgassupplierontheinstructions
tobefollowed iftheusersmells gas. Theseinstructionsmustbeposted ina
prominentlocationnearthedryer.
FORYOURSAFETY
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. 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.
Important
For your convenience, log the following information:
DATEOFPURCHASE________________________________ MODELNO. __________________________________________
DISTRIBUTOR’SNAME ____________________________________________________________________________________
Serial Number(s) ________________________________________________________________________________________
________________________________________________________________________________________
________________________________________________________________________________________
Replacement parts can be obtained from your distributor or JLA. When ordering replacement parts from JLA, you can FAX
your order to JLA at 01422 824390 or telephone your order directly to the JLA Parts Department at 01422 822282. 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.
D-78
Retain This Manual In ASafe 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.
The following “FOR YOUR SAFETY” caution must be posted near the dryer in a prominent location.

IMPORTANT
YOUMUSTDISCONNECTANDLOCKOUTTHEELECTRICSUPPLYANDTHEGAS
SUPPLY BEFORE ANY COVERS OR GUARDS ARE REMOVED FROM THE
MACHINETOALLOWACCESSFORCLEANING,ADJUSTING,INSTALLATION,OR
TESTING OF ANY EQUIPMENT PER OSHA (Occupational Safety and Health
Administration)STANDARDS.
CHILDRENSHOULDNOTBEALLOWEDTOPLAYONORNEARTHEDRYER(S).
WARNING
CHILDRENSHOULDBESUPERVISEDIFNEARDRYERSINOPERATION.
DRYERSSHOULDNEVERBELEFTUNATTENDEDWHILEINOPERATION.
CAUTION
FORYOURSAFETY
DONOTDRYMOPHEADSINTHEDRYER.
DONOTUSEDRYERINTHEPRESENCEOFDRYCLEANINGFUMES.
WARNING
UNDER NO CIRCUMSTANCES should the dryer door switches, lint drawer switch,
or heat safety circuit ever be disabled.
“Caution: Label ALL wires prior to
disconnection when servicing controls. Wiring
errors can cause improper operation.”
«Attention: Lordesopérations d’entretien
des commandes étiqueter tous fils avant
de les déconnecter. Toute erreur de
câblage peut étre une source de danger et
depanne.»

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
DRYERMUST NEVERBE 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.

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 .................................................................................................. 12
D. FreshAirSupplyRequirements ................................................................................................. 13
E. ExhaustRequirements ............................................................................................................... 14
F. ElectricalInformation ................................................................................................................ 18
G. GasInformation ........................................................................................................................ 24
H. Preparationfor Operation/Start-Up........................................................................................... 28
I. PreoperationalTests ................................................................................................................. 29
J. PreoperationalInstructions ........................................................................................................ 31
K. ShutDownInstructions ............................................................................................................. 32
SECTION IV
SERVICE/PARTS INFORMATION ......................................................................33
A. Service ..................................................................................................................................... 33
B. Parts ........................................................................................................................................ 33
SECTION V
WARRANTY INFORMATION...............................................................................34
A. ReturningWarrantyCards......................................................................................................... 34
B. Warranty .................................................................................................................................. 34
SECTION VI
ROUTINE MAINTENANCE ..................................................................................35
A. Cleaning ................................................................................................................................... 35
B. Adjustments ............................................................................................................................. 36
C. Lubrication ............................................................................................................................... 36
Table of Contents

SECTION VII
REVERSING TIMER SPIN/DWELL ADJUSTMENTS.....................................37
SECTION VIII
DATA LABEL INFORMATION .............................................................................38
A. DataLabel ............................................................................................................................... 38
SECTION IX
OPL SENSOR ACTIVATED FIRE EXTINGUISHING (S.A.F.E.) SYSTEM ..40
Installation ......................................................................................................................................41
SensorActivated FireExtinguishing(S.A.F.E.)SystemTheoryofOperation ....................................44
SystemReset..................................................................................................................................44
OPLS.A.F.E. System Check Procedure .........................................................................................44
SensorActivated FireExtinguishing (S.A.F.E.)System PartsBreak Down .......................................45
SECTION X
COIN SENSOR ACTIVATED FIRE EXTINGUISHING (S.A.F.E.) SYSTEM 47
Installation ......................................................................................................................................48
SensorActivated FireExtinguishing(S.A.F.E.)SystemTheoryofOperation ....................................51
DisabledSensorActivated Fire Extinguishing(S.A.F.E.)System ......................................................51
S.A.F.E.DiagnosticMessages ........................................................................................................51
SystemReset..................................................................................................................................51
SensorActivated FireExtinguishing (S.A.F.E.)System PartsBreak Down .......................................52

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.
JLA assumes no responsibility for freight claims or damages.
6. If you need assistance in handling the situation, please contact the JLATraffic Manager at 01422 822282.
IMPORTANT: The dryermustbe transportedandhandled inanupright position atALL times.

4
B. SAFETY PRECAUTIONS
WARNING: Foryoursafety,theinformation inthismanualmustbefollowedtominimize the riskof
fireorexplosion ortopreventproperty damage,personalinjury,orloss oflife.
WARNING: The dryermust neverbe operatedwithany of theback guards, outertops, or
servicepanelsremoved. PERSONALINJURYOR FIRE COULDRESULT.
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. Dryers must be exhausted to the outdoors.
6. Although the manufacturer 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 onlywater washed fabrics. DONOT dryarticles spottedorwashed indry cleaning
solvents,acombustibledetergent,or“all purpose”cleaner.
EXPLOSIONCOULDRESULT.
WARNING: DONOTdry ragsor articlescoatedor contaminatedwithgasoline, kerosene,oil, paint,
orwax.
EXPLOSIONCOULDRESULT.
WARNING: DONOTdrymop heads. Contaminationbywax orflammablesolvents willcreatea
firehazard.
WARNING: DONOTuseheat fordrying articles thatcontain plastic,foam,sponge rubber, or
similarlytexturedrubbermaterials. Dryinginaheatedbasket (tumbler)maydamage
plasticsor rubberand may bea firehazard.

5
7. A program shouldbe established 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 collection oflintinthe burnerarea andexhaustductworkcan createa potentialfire
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 switches, lint drawer switch, or heat safety
circuit ever be disabled.
WARNING: PERSONALINJURYORFIRECOULDRESULT.
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: Articlesleft inthe dryerafter thedrying andcooling cycleshave beencompleted 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%), 50 lbs (22.7 kg) of its rated capacity.
WARNING: YOUMUSTDISCONNECTANDLOCKOUTTHEELECTRICSUPPLYAND
THEGAS SUPPLYBEFOREANYCOVERS ORGUARDSAREREMOVED
FROMTHEMACHINETOALLOWACCESSFOR CLEANING,
ADJUSTING,INSTALLATION, ORTESTINGOFANYEQUIPMENTPER
OSHA(Occupational Safetyand HealthAdministration)STANDARDS.

6
Gas
SECTIONII
SPECIFICATIONS/COMPONENTIDENTIFICATION
A. SPECIFICATIONS
* For non-reversing models only.
** A minimum of 3/4” pipe must be supplied to the gas inlet for each dryer.
NOTE: Manufacturerreservestherightto make changesin specificationsatany timewithoutnotice or
obligation.
BASKET (TUMBLER) DIAMETER 44-1/2” 113 cm
BASKET (TUMBLER) DEPTH 24-7/8” 63.2 cm
BASKET (TUMBLER) MOTOR 1 HP* 0.746 kw
DOOR OPENING (DIAMETER) 31-3/8” 79.7 cm
BASKET (TUMBLER) VOLUME 22.4 cu. ft. 0.634 cu. m.
EXHAUST CONNECTION (DIAMETER) 10” 25.4 cm
DRYERS PER 20’/40’ CONTAINER 8/18
DRYERS PER 48’/53’ TRUCK 24/26
VOLTAGE AVAILABLE 120-460v 1ø-3ø 50/60 Hz
APPROX. WEIGHT (UNCRATED) 888 lbs 402.8 kg
APPROX. WEIGHT (CRATED) 938 lbs 425.5 kg
HEAT INPUT 204,000 btu/hr 51,408 kcal/hr
AIRFLOW 60 Hz 1,200 cfm 33.98 cmm
AIRFLOW 50 Hz 1,008 cfm 28.54 cmm
INLET PIPE CONNECTION** 3/4” F.P.T.
Shaded areas are stated in metric equivalents

7
Specifications
D-78
NOTE: Manufacturerreservestherightto make changesin specificationsatany timewithoutnotice or
obligation.

8
B. COMPONENT IDENTIFICATION
1. Dryer Front View
Illus. No. Description
1 Controls
2 Control (top access) Door Assembly
3 Main DoorAssembly
4 Lint CompartmentArea (lint screen located behind door)
5 Data Label and Installation Label
(located in the left side panel/wall area behind the control door)

9
2. Dryer Rear View
Illus. No. Description
1 Heating Unit
2 Outer Top Area
3* Electric Service Relay Box
4 Basket (tumbler) Bearing Mount Assembly
5 Idler Bearing MountAssembly
6 Basket (tumbler) (drive) MotorAssembly (for reversing models only)
7 Blower MotorAssembly
8 Dryer Exhaust
* Electrical service connections are made in this box.

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/NFPANO. 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 LATEST EDITION
(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: “The dryermustbeinstalledonnoncombustible floors only.”
2. The dryer must not be installed or stored in an area where it will be exposed to water and/or weather.
3. Provisions for adequate air supply must be provided as noted in this manual (refer to Fresh Air Supply
Requirements in Section D).
4. Clearance provisions mustbe made from combustible construction as noted in this manual (refer to Dryer
Enclosure Requirements in Section C).
5. 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).
6. Dryer must be exhausted to the outdoors as noted in this manual (refer to Exhaust Requirements in
Section E).
7. 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: Dryer shouldbe locatedwhere a minimumamountof exhaustductwillbe necessary.
9. The dryer must be installed with a proper exhaust duct connection to the outside.
10. The dryer must be installed with provisions for adequate combustion and make-up air supply.

11
CAUTION: Thisdryer producescombustiblelint andmustbeexhausted tothe outdoors. Every 6
months,inspecttheexhaustductingandremoveanylintbuildup.
B. UNPACKING/SETTING UP
Remove protective shipping material (i.e., plastic wrap, and/or optional shipping box) from dryer.
IMPORTANT: Dryer mustbetransportedand handledinanupright positionat 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) 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.
To increase bearing life and improve efficiency, the dryer should be tilted slightly to the rear.
The lint coops of ALL D-78 dryers are supported during shipping by a bracket. REMOVE THIS BRACKET
BEFORE STARTING THE DRYER.
If more headroom is needed when moving dryer into position, the top console (module) may be removed.
1. To Remove Top Console (module)
a. Disconnect the ground wire (A) at the rear upper left hand corner of dryer.
b. Remove the four (4) sets of nuts and
washers (B) holding the console
(module) to base.
c. Open the control door/control panel
and disconnect the white 9-pin plug
connector (C) located in the base of
the control box.
d. Disconnect motor harness(es) (D)
located in rear electrical box.
e. Disconnect 2-pin connector (E)
located in rear electrical box. (On
some dryers, this is optional.)
f. Liftthe console (module) offthedryer
base.

12
C. DRYER ENCLOSURE REQUIREMENTS
Bulkheads and partitions must be made of noncombustible materials and must be located a minimum of
12-inches (30.48 cm), 18-inches (45.72 cm) 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 4-inches (10.16 cm) and must
not extend more than 4-inches (10.16 cm) to the rear of the front. The bulkhead facing must not be closed in
ALL the way to the top of the dryer. A 1-inch (2.54 cm) clearance is required.
NOTE: Allowancesmustbemadefor openingthecontrol door.
Dryers may be positioned sidewall to sidewall. However, a 1/16” (1.5875 mm) minimum allowance must be
made for the opening and closing of the control door and the lint door. It is suggested that the dryer be positioned
about 2 feet (0.61 meters) 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: Airconsiderationsare important forproperandefficientoperation.
IMPORTANT: Even thoughaminimum ofonly12-inches (30.48cm)is requiredbehind the dryer,
18-inches(45.72cm)or moreis suggested(especially whenverticalventingisused).
Theadditionalclearanceisadvantageous foreaseof installationand service.
IMPORTANT: When firesprinkler systemsare locatedabove thedryers, aminimum of18-inches
(45.72cm) abovethedryer console(module)is required. Dryersmay be positioned
sidewalltosidewall,however,a 1/16” (1.5875mm)minimumallowance is required
betweendryers(or wall)for easeof installationandmaintenance. Allowancesmust
bemade fortheopening andclosingof thecontroldoor andthelint door.

13
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 mustbe 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 airflow of 1,200 cfm (cubic feet per minute) (33.98
cmm [cubic meters per minute]) must be supplied to each gas dryer. As a general rule, an unrestricted air
entrance from the outdoors (atmosphere) of a minimum of 1-1/2 square feet (0.41 square meters) is required for
each dryer. The dryer must be installed with provisions for adequate combustion and make-up air supply.
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 separate make-up air openings 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 x 1-1/2 feet (0.60 meters
x 0.45 meters) (6 square feet [0.56 square meters]) 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-up airmustbeprovidedfroma sourcefreeof drycleaningsolvent fumes.
Make-upairthatiscontaminatedbydrycleaningsolventfumeswillresultin
irreparabledamage tothemotors andotherdryer components.
NOTE: ComponentfailureduetodrycleaningsolventfumeswillVOIDTHEWARRANTY.

14
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-limit 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: IMPROPERLYSIZED ORINSTALLEDEXHAUSTDUCTWORKCAN
CREATEAPOTENTIALFIREHAZARD.
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.
HORIZONTAL VENTING:
When single dryer venting is used, the length of the ductwork from the dryer to the outside exhaust outlet
must not exceed 15 feet (4.6 meters). The minimum diameter of this ductwork must be at least
10-inches (25.4 cm). In the case of multiple (common) dryer venting, the distance from the last dryer to the
outside exhaust outlet must not exceed 15 feet (4.6 meters). The shape of the ductwork is not critical so
long as the minimum cross-sectional area is 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 preferably be 1-1/2 times the
diameter of the duct. Including 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. ALL ductwork
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.
ALLductwork joints mustbe taped to prevent moisture and lint from escaping into the building. Inspection
doors shouldbe installed at strategic points in the exhaust ductwork for periodic inspection and cleaning of
lint from the ductwork.
VERTICAL VENTING:
When single dryer venting is used, the length of the ductwork from the dryer to the outside exhaust outlet
must not exceed 20 feet (6.1 meters). The minimum diameter of this ductwork must be at least
12-inches (30.48 cm). In the case of multiple (common) dryer venting, the distance from the last dryer to
the outside exhaust outlet must not exceed 20 feet (6.1 meters). The shape of the ductwork is not 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 instead. The radius of the elbows should preferably be 1-1/2 times the
diameter of the duct. ALL ductwork 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 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.

15
IMPORTANT: Exhaust backpressure measuredbya manometerin the exhaustductmustbeno less
than 0 and mustnot exceed0.3 inches (0.74 mb) of water column (W.C.).
IMPORTANT: Minimum ductwork diameterforhorizontalventingis 10-inches(25.4cm)andfor
verticalventingtheminimumis12-inches(30.48cm).
NOTE: Whentheexhaust ductwork passesthroughawall, ceiling, orroofmadeofcombustible
materials,the opening mustbe2-inches (5.08cm)larger thantheduct (all thewayaround).
Theductmustbecenteredwithin thisopening.
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: DO NOTuse screens,louvers, orcaps onthe outsideopening oftheexhaust
ductwork.
2. Single Dryer Venting
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-sectional area is
provided.
IMPORTANT: Minimum ductsize fora dryerthat isvented horizontallyis 10-inches(25.4 cm)for a
roundduct oranequivalent of80square inches(516.3 square centimeters). THE
DUCTSIZEMUSTNOT BEREDUCEDANYWHERE DOWNSTREAM OF
THEDRYER.
IMPORTANT: Exhaust backpressure measuredbya manometerin the exhaustductmustbeno less
than 0 and mustnotexceed0.3inches (0.74mb) ofwater column.
IMPORTANT: It isrecommendedthat exhaust orbooster fansnot beused in theexhaust ductwork
system.

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IMPORTANT: Minimum ductsize foradryerthat isvented verticallyis 12-inches(30.48cm)for a
roundduct oranequivalent of120square inches(774.2 squarecentimeters). THE
DUCTSIZE MUSTNOTBE REDUCEDANYWHEREDOWNSTREAM OF
THEDRYER.
IMPORTANT: For extendedductwork runs,the crosssection areaof the ductworkcan onlybe
increasedtoan extent. When theductwork approachesthemaximumlimitsnoted in
thismanual,aprofessionalheating,venting,andairconditioning(HVAC)firmshould
beconsultedforproperventinginformation.
ALLductwork 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 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.
NOTE: Whentheexhaust ductwork passesthroughawall, ceiling, orroofmadeofcombustible
materials,the openingmustbe2-inches (5.08cm)larger thantheduct (alltheway around).
Theductmustbe centeredwithinthis opening.
IMPORTANT: It isrecommendedthat exhaust orbooster fansnot beused in theexhaust ductwork
system.